How does a thermal power plant (CHP) work? Steam turbine installations of thermal power plants (TPPs) Design features of the turbogenerator

Turbine generators are the world's main machine that generates AC electricity. For the first time, three-phase current turbogenerators with a cylindrical rotor appeared in 1900-1901. After that, there was their rapid development both in design and in the growth of unit capacities. The largest turbogenerators in the period 1900-1920 were manufactured with six poles due to the limited possibilities of metallurgy in the manufacture of forgings for rotors. In 1920, the most powerful for that time was manufactured in the USA

Rice. 6.2. Model of a 1200 MW turbogenerator with a rotation speed of 3000 rpm at the Kostroma State District Power Plant

turbine generator with a capacity of 62.5 MW, a rotation speed of 1200 rpm. Two-pole turbogenerators were made with a capacity of only up to 5.0 MW.

After 1920, two- and four-pole turbogenerators received the main development. The unit capacities of these machines grew rapidly. England, Germany, Russia, USA, France, Switzerland, and Japan have been and remain the leading countries in the field of turbogenerator construction.

The first turbogenerator in our country with a capacity of 500 kW was manufactured in 1924 by the Electrosila plant. In the same year, two more turbogenerators with a capacity of 1500 kW each were manufactured. These first machines formed the basis for the creation in subsequent years of a series of turbogenerators in the power range from 0.5 to 24 MW at a speed of 3000 rpm. For 1926 and 1927 29 such turbogenerators were made. These machines were created under the guidance of the outstanding production engineer A.S. Schwartz.

In the early 1930s, a new series of turbogenerators with capacities from 0.75 to 50 MW was created at the Elektrosila plant. It was essential that the experience of Western Europe and the USA in turbine generator building was widely used in the creation of this series. Compared with the previous series, it was possible to reduce the mass of copper in the stator winding by 30%, and electrical steel by 10-15%. At the same time, the labor intensity of manufacturing machines was reduced. All electromagnetic, thermal, ventilation and mechanical calculations were performed using new calculation methods. The machines were made from domestic materials. Already by January 1, 1935, 12 such turbine generators with a capacity of 50 MW each were installed at domestic thermal power plants.

On the basis of the latest series of turbogenerators, developments were carried out and the production of high-speed turbo engines with a power of 1 to 12 MW with a rotation speed of 3000 rpm for turbo blowers and turbo compressors began.

Of particular importance is the cycle of research and development, which culminated in 1937 with the manufacture of the most powerful 100 MW turbogenerator in the world with a rotation speed of 3000 rpm and indirect air cooling. The main difficulties were associated with the rotor. Metallurgists coped with the creation of large-sized forgings from high-quality steel, and electrical machine builders - with its machining - which required exceptionally high precision.

Under the leadership of R.A. Luther and A.E. Alekseev, calculations were made and designs of pre-war series of turbogenerators and individual machines were developed.

In subsequent years, it became necessary to master turbogenerators of greater power - 200 and 300, and in subsequent years 500, 800, 1000 and even 1200 MW at a speed of 3000 rpm (Fig. 6.2). The main problems in the creation of turbogenerators of such capacities are created by the limitation of the rotor diameter and the distance between its supports. In the first case, the limitation is due to mechanical strength, and in the second case, due to vibrations. Under these conditions, an increase in power is achieved through the use of more intensive cooling methods, which make it possible to increase the current density in the windings. The complexity in this case lies in the need not only to maintain, but also to slightly increase the efficiency, as well as to reduce vibrations. All this required a very large amount of theoretical and experimental research, the creation of experimental machines and the construction of unique test benches.

Research, development and production of powerful turbogenerators were carried out in the USSR at three plants: Elektrosila (Leningrad), Electrotyazhmash (Kharkov) and Sibelektromash (Novosibirsk). Each plant created its own designs and technological processes.

For the first time in the world practice, the Electrosila plant proposed and mastered hydrogen cooling of rotors with intakes and deflectors, as well as water cooling of the stator winding. All work was initially carried out under the supervision of the chief engineer of the plant D.V. Efremov, chief designers E.G. Komar and N.P. Ivanov, and then chief engineer Yu.V. Aroshidze, chief designer of turbogenerators G.M. Khutoretsky and the head of scientific, technical and experimental design works of the plant L.V. Kurilovich. Hydrogen is a better refrigerant than air. The use of hydrogen began with a 100 MW, 3,000 rpm turbogenerator, which was manufactured in 1946. It had indirect hydrogen cooling for the rotor and stator windings. It is quite natural that the stator core cooling system was in principle the same as with air cooling. It required a transition from indirect cooling of the windings to direct. Diagonal channels were made in the rotor coils, hydrogen was supplied to which was carried out by intakes, and the removal was carried out by deflectors. Intakes and deflectors - wedges for fastening the winding with shaped holes for the passage of gas. With an increase in power, an increase in the hydrogen pressure was required. Thus, the gas was in direct contact with the copper of the rotor. The stator winding rods were made of hollow copper conductors, between which solid conductors were laid. Water, flowing through the hollow conductors, provided direct cooling of the stator winding.

To radically reduce the vibrations of machine bodies, an elastic connection was used between the core and the body. This was achieved by using longitudinal slots in the rectangular ribs on which the core is assembled.

Particular difficulties arose in the creation of a turbogenerator with a capacity of 800 MW. In connection with very large electrodynamic forces and operating conditions close to resonant, the usual methods of fastening the frontal parts of the windings turned out to be unacceptable. Monolithic fastening has been achieved with the help of new fastening materials: a soft material formed at room temperature, i.e. in the manufacturing process of the machine, and hardening at elevated temperatures, as well as self-shrinking lavsan cords.

Under the leadership of A.B. Shapiro and I.A. KadiOgly developed original turbogenerators with even more intensive water cooling of the rotor and stator windings, the stator core and some structural elements. The first fully water-cooled turbogenerator with a capacity of 63 MW and a speed of 3000 rpm was put into operation in 1969. Subsequently, three more such machines were made. In 1980, a turbogenerator with a capacity of 800 MW and a rotation speed of 3000 rpm was turned on. In the future, four more machines began to work. In their design, the supply and discharge of water was carried out in addition to the shaft. Water from a fixed pipe enters the zone of the shaped ring on the rotor and is retained in it by centrifugal forces. Further, the water goes to the lower terminals of the coils of rectangular wires with holes and, under the action of centrifugal forces, enters the upper terminals and the drain ring. Such a system is called self-pressure. It should be noted that all over the world water supply to the rotor winding and its removal occur through holes in the shaft, which makes the design very complex and less reliable. The advantage of this class of turbogenerators is the exclusion of hydrogen and the filling of the vessel with air at atmospheric pressure.

At the plant "Electrotyazhmash" (Kharkov), the development and manufacture of turbogenerators with a capacity of 200, 300 and 500 MW and a speed of 3000 rpm were carried out by the chief designer of the plant L.Ya. Stanislavsky, Deputy Chief Designer V.S. Kildishev, chief engineer N.F. Ozerny and production manager I.G. Grinchenko. Methods for calculating turbogenerators, especially the end zone, were developed by the head of the department of the Institute of Electrodynamics of the Academy of Sciences of the Ukrainian SSR I.M. Postnikov.

In a 200 MW machine, the rotor is hydrogen-cooled and the stator is water-cooled. The 300 MW turbogenerator uses direct hydrogen cooling for both the rotor and stator windings. The rotor uses axial-radial ventilation. Thin-walled steel tubes are laid in the core of the stator winding, through which gas passes. In turbogenerators with a power of 500 MW, the stator and rotor windings are formed from hollow and solid conductors. Water is supplied to the rotor winding and removed from it through holes in the shafting.

At the plant "Sibelektrotyazhmash" (Novosibirsk) a turbine generator with a capacity of 500 MW and a speed of 3000 rpm was mastered with oil cooling of the stator and core windings and water cooling of the rotor winding. Inside the stator bore, a glass tape cylinder is inserted and hermetically fixed in the shields. Oil flows from one side of the stator to the other through channels in the winding bars and through axial holes in the core. Water is supplied to the rotor winding through the shaft line. The voltage of the stator winding is 35 kV, which greatly facilitates the current supply from the generator to the step-up transformer.

P.E. Bazunov, K.F. Potekhin and K.I. Maslennikov.

Significant work was carried out at the Lysva Turbine Generator Plant (Lysva, Perm Region) in the field of medium power turbogenerators. Synchronous two-pole motors with a power of 630-12,500 kW, voltages of 6 and 10 kV were especially highly appreciated. They are used in the drives of oil pumps of main oil pipelines, superchargers of main gas pipelines, blowers of blast furnaces, gas compressors of chemical industries, etc. Their development was completed in 1980.

Compared to the previous series, the weight of the engines of the new series is reduced by 1.5-2 times, the efficiency is increased by 0.5-2%, the labor intensity of manufacturing is reduced by 1.5 times and the output is increased by 3 times without increasing production areas. In terms of their technical level, the engines exceeded the performance of the best world models. The most significant contribution to the calculations and designs of engines was made by E.Yu. Fleiman and V.P. Glazkov, and in the excitation system - S.I. Loginov.

Summing up the results of the historical development of turbogenerators in the postwar years, it should be noted the success of the scientific and technical activities of the teams of several plants, as a result of which turbogenerators of various designs were created and mastered in production. However, the presence of various structures complicates the design and construction of power plants, installation, adjustment and repair work, as well as the provision of spare parts. Therefore, within the framework of one country, it becomes desirable to produce machines of a single design. In foreign practice (France, England, Sweden, Switzerland), this problem is solved by combining electrical engineering firms and specializing in production. In our country, in order to create a single unified series of turbogenerators for all plants, a comprehensive research and development program for machines of a single series was developed and implemented (supervisor I.A. Glebov, deputy scientific supervisor Ya.B. Danilevich, chief designer GM Khutoretsky, chief technologist Yu.V. Petrov). The requirements for the new series were formulated with the participation of experts from member countries of the Council for Mutual Economic Assistance. The series was based on hydrogen-hydrogen cooled turbogenerators produced by the Elektrosila association, since their number was the largest and there was a positive experience of their operation in the entire power range from 63 to 800 MW at a speed of 3000 rpm. The development of turbogenerators of a single unified series began in 1990.

The major achievements of foreign firms in the field of turbogenerators include the following. Alstom-Atlantic produced a series of four-pole turbogenerators with a capacity of 1600 MVA for nuclear power plants; the limiting power of four-pole turbogenerators for nuclear power plants manufactured by Siemens is about 1300 MW ∙A. ABB has mastered the production of turbogenerators with a capacity of 1500 MV∙A, 1800 rpm, 60 Hz and turbogenerators with a capacity of 1230 MV∙A, 3000 rpm, 50 Hz. American and Japanese firms produce turbogenerators with a maximum power of about 1100 MVA. All firms, with the exception of Siemens, use hydrogen-water cooling. Siemens uses water cooling for windings not only of stators, but also of rotors.

It is necessary to pay attention to the ever-increasing production of turbogenerators

Rice. 6.3. General view of the impact turbogenerator (inertial energy storage)

1,1,3 - bearing, stator and rotor shaft of a 200 MW turbogenerator, respectively; 4.5.6 - bearing, shaft, flywheel housing, respectively; 7 - asynchronous motor; 8 - foundation rafts

medium power - up to 250 MW for thermal power plants with a combined cycle (two gas turbines and one steam).

In recent years, the use of combined cycle plants has begun. Since the maximum capacity of gas turbines is currently 150-200 MW, the combined cycle gas system with a capacity of 450-600 MW consists of three units: two with gas turbines and one with steam. Since such units require relatively small power turbogenerators (150-200 MW), they returned to air cooling to simplify their design. The first air-cooled turbogenerator with a capacity of 150 MW and a rotation speed of 3000 rpm was manufactured for the Severo-Zapadnaya CHPP in 1996 at Elektrosila JSC.

Short-term impact turbogenerators belong to a special class. They are used for testing circuit breakers, for experimental installations of thermonuclear fusion based on tokamaks, large plasmatrons, mass accelerators, etc. For the experimental tokamak with a superstrong field, four two-pole turbogenerators with a power of 200 MW (242 MV A) were developed and built. Such turbogenerators are created for the first time in world practice (Fig. 6.3). They use indirect air cooling. In order to reduce the dimensions, the generators are made with increased saturation of the magnetic circuit. On the common shaft with the generator there is an inertial accumulator made on the basis of the rotor of a turbogenerator with a capacity of 800 MW. The stored energy in the generator is 100 and in the flywheel is 800 MJ. The specific energy intensity of the generator rotor is 5, and the flywheel is 10 J/g. The pulse duration is 5 s. During the release of stored energy, the speed is reduced to 70%. Thus, 50% of the energy is used. The specific cost of the accumulated energy is the lowest compared to the cost of energy of other types of storage devices. The amount of energy can be brought up to 2500 MJ by using stronger steel and increasing the diameter of the flywheel. The unit is started by an asynchronous motor with a phase rotor on the unit shaft or a frequency converter powered by the mains. I.A. Glebov, E.G. Kasharsky and F.G. Rutberg developed calculation methods, carried out technical studies of various options and their comparison, justification of the turbogenerator design, in contrast to the hydrogenerator used in foreign practice. The project was carried out by G.M. Khutoretsky, and metallurgical problems were solved by A.M. Shkatova.

It should be noted that in the early 1920s Russian scientists M.P. Kostenko and P.L. Kapitsa made a project and implemented the first impact generator to create strong magnetic fields.

At the Tomsk Polytechnic Institute, under the guidance and with the direct participation of G.A. Sipailov, a scientific school was created in the field of electromachine generation of pulsed powers in autonomous modes. Numerous studies have been carried out, calculation methods have been developed, and a number of pulse generators have been created. Among the original solutions are electric machine generators with non-salient-pole laminated rotor and pulse forcing of excitation due to magnetization in asymmetric modes with serial switching of the stator and rotor windings.

A fundamentally new direction is superconducting turbogenerators, which have 2 times less weight and losses. It is quite natural that experimental low-power superconducting machines (synchronous, unipolar, direct current) were first created.

The following superconducting machines were created at VNIIelectromash: a 3 kW DC collector motor, a synchronous generator with a power of

Rice. 6.4. Test stand with a superconducting turbogenerator with a power of 20 MVA (in the center of the figure)

18 kW, 10 kA unipolar generator at 24 V and 1200 kW synchronous generator. The first four machines were created under the guidance and with the direct participation of V.G. Novitsky and V.N., Shakhtarin. G.G. also made a significant contribution to the development and implementation of a 3 kW DC motor. boards. A 1200 kW synchronous generator was designed and manufactured under the direction of V.V. Dombrovsky.

The first medium power generator (20 MP A) was created at VNIIelectromash in 1979. (Fig. 6.4) . The machine was studied and tested in detail at the institute's stand and while working at Lenenergo. The rotor has a niobium-titanium alloy winding. It is cooled by liquid helium (4.2 K), which enters the inside of the rotor through a fixed tube in the central hole of the shaft. The return of helium in the gaseous state also occurs through the shaft. To protect the superconducting winding from heat inflow from the external environment, the rotor has three cylinders, the space between which is evacuated.

Research and development work at the All-Union Scientific Research Institute of Electromechanics (VNIIEM) ended with the creation of a number of superconducting machines. The first machine had a power of 600 watts. It was a generator with a superconducting excitation winding on the stator and a three-phase winding on the rotor. The next machine was a 25 kW commutator motor, followed by a 100 kW alternator with a superconducting inductor, a 200 kW AC cryo motor with a fixed cryostat, model synchronous generators with a rotating cryostat, a unique synchronous-asynchronous motor with torque transmission without mechanical joints of machines . The head, organizer of production and co-executor of research and development was N.N. Sheremetevsky. The main developer of superconducting inductors was A.S. Veselovsky, and anchors - A.M. Rubenraut.

The creator of a synchronous superconducting non-salient-pole generator with a power of 200 kW at the Kharkov plant "Electrotyazhmash" was V.G. Danko.

At the Physico-Technical Institute for Low Temperatures (FTINT, Kharkov), the initiator, organizer and supervisor of all work in the field of using the phenomenon of superconductivity was B.I. Verkin. The works of Yu.A. Kirichenko, A.V. Pogorelov and G.V. Gavrilov.

FTINT created: a cryoturbine generator with a capacity of 200 kW with a fixed excitation winding and a warm rotating armature, a turbogenerator with a capacity of 2 and 3 MW with superconducting rotors (together with the Elektrosila association). The last two machines were created with the participation of specialists from the Electrosila association I.F. Filippova and I.S. Zhytomyr. Much work has been done in the field of unipolar superconducting machines: a 100 kW disk armature motor, a 150 kW machine with a cylindrical rotor, and then 325 and 850 kW motors.

A significant contribution to the theory and methods of calculating electrical machines using the phenomenon of superconductivity was made by the scientists of the Moscow Aviation Institute A.I. Bertinov, B.L. Alievsky, L.K. Kovalev and others.

In a 20 MVA generator, the outer cylinder of the rotor has room temperature, the inner cylinder has the temperature of liquid helium, and the middle one is 70 K. The winding is formed by racetrack coils of different widths and is rotated in a helium bath formed by the inner cylinder and end parts. Due to the very large MMF, there is no need to use steel for the rotor. Under these conditions, the stator can be made slotless. which increases the amount of copper and power by approximately 2 times. For low external magnetic induction, a ferromagnetic screen is used in the stator. Research, development of calculation methods and technological processes, manufacturing and testing were carried out under the guidance and with the direct participation of I.A. Glebova, Ya.B. Danilevich, A.A. Karshova, L.I. Chubraeva and V.N. Shakhtarin.

I.A. Glebov was the supervisor, Ya.B. Dakilevich - chief designer, A.A. Karymov - the author of new methods of mechanical calculations, L.I. Chubraev - a specialist responsible for the manufacture of the stator and testing of the superconducting turbogenerator in the power system. V.N. Shakhtarin - a specialist responsible for the development and manufacture of the rotor. Since low temperatures are obtained using cryogenic technology, the creative participation in the development and testing of a generator with a capacity of 20 MVA by the specialists of the Scientific Research Institute "Geliymash" I.P. Vishneva, A.I. Krause was very important.

I.P. Vishnev carried out the development and management of work on the creation of devices for cryogenic technology, A.I. Krause carried out commissioning and testing of cryogenic devices. Of particular importance was their participation in the work to determine the minimum duration of the cooling down of the rotor, which is permissible under the conditions of the mechanical strength of its elements.

Under the leadership of I.F. Filippov as a developer of methods for calculating thermophysical processes and a leader in the creation of a unique cryogenic stand and G.M. Khutoretsky as the chief designer in the Electrosila association created a superconducting turbogenerator with a capacity of 300 MW and a rotation speed of 3000 rpm. The stator and rotor have been successfully tested at liquid nitrogen temperature. However, the insufficient gas tightness of the outer cylinder did not allow to have the necessary vacuum and reach the design mode with liquid helium.

Superconducting turbogenerators belong to the future generation of turbogenerators. Work in this direction is being carried out in a number of countries.

The United States, the states of Western Europe and Japan have made significant progress in the field of research and development of superconducting electrical machines. Japan and the United States have achieved the greatest success in the field of superconducting turbogenerators. The main elements of a superconducting turbogenerator with a power of 800 MVA have been created in the FRG. Japan has a national program with the ultimate goal of conquering the world market in the field of turbogenerator construction based on the use of the superconductivity phenomenon. At present, three superconducting turbogenerators with a capacity of 70 MVA each are being manufactured in Japan. The greatest achievements in the field of unipolar superconducting machines include the results of the work of the British company IRD (2.42 MW unipolar engine).

The above review in the field of superconducting machines, and primarily turbogenerators, shows that our country is at the forefront in the world.

Through the rotating magnetic field of the rotor in the stator. The rotor field, which is created either by permanent magnets mounted on the rotor, or by a DC current flowing in the copper winding of the rotor, leads to the appearance of a three-phase alternating voltage and current in the stator windings. The voltage and current on the stator are greater, the stronger the rotor field, i.e. more current flowing in the rotor windings. For synchronous turbogenerators with external excitation, the voltage and current in the rotor windings are created by a thyristor excitation system or an exciter - a small generator on the turbogenerator shaft. Turbogenerators have a cylindrical rotor mounted on two plain bearings, in a simplified form, it resembles an enlarged car generator. 2-pole (3000 rpm), 4-pole (1500 rpm as at the Balakovo NPP), and multi-pole machines are produced, depending on the places of operation and the requirements of the Customer. According to the methods of cooling the turbogenerator windings, they are distinguished: with liquid cooling through the stator jacket; with liquid direct cooling of windings; air-cooled; with hydrogen cooling (more often used at nuclear power plants).

History

One of the founders of ABB, Charles Brown, built the first turbogenerator in 1901. It was a 100 kVA 6-pole generator.

The advent of powerful steam turbines in the second half of the 19th century led to the need for high-speed turbogenerators. The first generation of these machines had a stationary magnetic system and a rotating winding. But this design has a number of limitations, one of them is low power. In addition, the rotor of a salient pole generator is not able to withstand large centrifugal forces.

The main contribution of Charles Brown to the creation of the turbogenerator was the invention of the rotor, in which its winding (excitation winding) fits into the grooves that are obtained as a result of the machining of the forging. Charles Brown's second contribution to the turbogenerator was the development in 1898 of a laminated cylindrical rotor. And, ultimately, in 1901, he built the first turbogenerator. This design is used in the production of turbogenerators to this day.

Types of turbogenerators

Depending on the cooling system, turbogenerators are divided into several types: air-cooled, oil-cooled, hydrogen-cooled, and water-cooled. There are also combined types, such as hydrogen-water-cooled generators.

There are also special turbogenerators, for example, locomotive ones, which serve to power the lighting circuits and the locomotive radio station. In aviation, turbogenerators serve as additional on-board sources of electricity. For example, the TG-60 turbogenerator operates on compressed air taken from the aircraft engine compressor, providing a drive for a three-phase alternating current generator of 208 volts, 400 hertz, with a rated power of 60 kV * A.

Turbogenerator design

The generator consists of two key components - the stator and the rotor. But each of them contains a large number of systems and elements. The rotor is a rotating component of the generator and is subjected to dynamic mechanical loads, as well as electromagnetic and thermal loads. The stator is a stationary component of a turbogenerator, but it is also subject to significant dynamic loads - vibration and torsional, as well as electromagnetic, thermal and high voltage.

Generator rotor excitation

The initial (exciting) direct current of the generator rotor is supplied to it from the generator exciter. Usually, the exciter is coaxially connected by an elastic coupling to the generator shaft and is a continuation of the turbine-generator-exciter system. Although at large power plants, backup excitation of the generator rotor is also provided. Such excitation comes from a separate pathogen. Such DC exciters are driven by their three-phase AC motor and are included as a reserve in the circuit of several turbine plants at once. From the exciter, direct current is supplied to the generator rotor by means of a sliding contact through brushes and slip rings. Modern turbogenerators use thyristor self-excitation systems.

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Literature

Woldek A.I. Electric machines. Energy. L. 1978
Operation and Maintenance of Large Turbo Generators, by Geoff Klempner and Isidor Kerszenbaum, ISBN 0-471-61447-5, 2004

Notes

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An excerpt characterizing the Turbogenerator

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We didn't choose, we just walked. But we will be happy if you have something to offer us.
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1. Turbine specifications

Type	extraction condensing turbine
number of buildings	1
number of emergency brake valves number of nozzle group valves	2 4
regulation stage:
type average diameter	impulse 800 mm
number of blade holders number of reaction steps	2 14
average diameters
first stage last step	570 mm 1000 mm
last stage blade length	285 mm
main steam to turbine (inlet flange)
pressure temperature	12 bar(g) 340 °С
number of issues relief pressure 1 at rated power	2 6.2 barg
relief pressure 2 at rated power exhaust pressure at rated power	1 barg 0.11 barg
rated power rated speed	12000 kW 5000 min -1
driven mechanism	generator
compound	with transmission
Max. main steam consumption	18.92 kg/s

1.1. Gearbox Specifications

1.2. Generator Specifications

design design according to	IM 1001 IEC-UTE
Max. height excitation	1000 m brushless
protection class insulation class	IP 54 F
temperature class cooler location	B installed on the stator
number of coolers cooler performance	2 60% each
current type full power	3ph / synchronous 15000 kVA
rated power power factor (cos φ)	12000 kW 0,8
voltage frequency	10.5 kV 50 Hz
speed cooling	1500 min -1 air / water cooler
cooling water quality inlet cooling water temperature	ST 25 °С
cooling water consumption	approx. 60 m3/h
bearing: plain bearing with oil lubrication (total oil supply with turbine)

1.3 Oil supply

To provide the turbine and driven mechanism with lubricating oil / operating oil / governor oil / lifting oil. Turbine oil quality according to DIN 51515 type ISO viscosity grade VG46.

approx. lubricating oil pressure	3.5 bar
approx. Pilot oil pressure	160 bar
approx. lifting oil pressure	100 bar
approx. reserve oil pressure	2 bar
oil tank contents	6000 l
quantity of the first filling of the oil tank	6600 l
number of circulations (per hour)	˂8 1/h
oil filter mesh width	25 µm
Max. diff. oil filter pressure	1 bar
oil cooler	2 x 100%
oil cooler location	vertical
inlet cooling water temperature	30 °С
approx. pressure loss on the water side	0.25 bar
cooling water quality	ST
approx. cooling water consumption	55 m3/h

1.4 Capacitor specifications

1.5 Technical data of the condensate pump

1.6 Pumping system

Type	steam ejector
main ejector
number of ejector groups	2
number of steps in a group	2
number of ejection capacitors execution	1 horizontal
starting ejector
number of ejectors	1
number of steps	1
steam release	to the atmosphere through the muffler
working steam
pressure	6.2 barg
temperature	279 °С
number	0.1 kg/s
cooling medium	condensate
coolant inlet temperature
nominal	47 °C
Max.	70 °С

2. Working data

2.1 Steam conditions

Rated main steam up to turbine (inlet flange)

*) initial pressure should not exceed:
105% of nominal pressure at any time, but the average pressure does not exceed 100% for any 12 months of operation
120% of nominal pressure as a one-time value, but not more than 12 hours during 12 months of operation
**) temperature rise should not be more than:

In no case should the temperature exceed the nominal temperature by more than 28 °C.

If steam is supplied to any end point of the turbine through 2 or more parallel pipes, the temperature of the steam in any pipe shall not differ from the temperature in any other pipe by more than 17 °C, except that in cases of fluctuation not exceeding 15 minutes , the temperature difference in the hottest pipe must not exceed the limits indicated earlier.

2.2 Steam quality

The values specified in the VGB directive (VGB-R 450L - edition 1988) for boiler feed water, boiler water and steam from water tube boilers must not be exceeded during continuous operation.

For continuous operation, the steam requirements for steam turbines are as follows:

*) at 25 °C, in local flow with continuously operating measuring point downstream of the strongly acidic cation exchanger
(only applies to water that does not contain CO2).
Exceeding the VGB values even for a short time can lead to the formation of strong salt deposits, which causes mechanical and corrosion damage.

2.3 Performance data

The following data refer to the main steam rating at the turbine inlet flange. Performance data refer to turbine/generator clutch/generator contacts. The indicated pressure data are calculated from the outlet pipes of the turbine.

load point			BUT
fresh steam
	pressure	bar (ex.)	12
	temperature	°C	340
	steam consumption	kg/s	18,92
Selection 1
	pressure	bar (ex.)	6,2
	number	kg/s	1,166
Selection 2
	pressure	bar (ex.)	1
	number	kg/s	1,319
outlet steam
	pressure	bar (ex.)	0,11
	number	kg/s	16,41
Condenser cooling water
	consumption	kg/s	695
	inlet temperature	°C	30
Generator
	frequency	Hz	50
	voltage	kV	10,5
	Power factor	cos phi	0,8
	coolant temperature inlet water	°C	25

Electrical power (generator contacts)		kW	12000

2.4 Warranty

2.4.1 Thermodynamic warranty

We guarantee compliance with the electrical output indicated in column A in the section "Performance data", provided that the required control valves are fully open. The values apply to the specified conditions.
Steam quality according to VGB (CES Operators Association) standards.
The following standards apply in their latest versions for acceptance testing: DIN 1943 VDI Steam Turbine Code.
Tolerance for max. performance: ±0%
Design tolerances: ±0%
Measurement tolerances acc. DIN

2.4.2 Vibration warranty

Dynamically balanced rotor according to ISO 1940 rotor class G2.5
Required vibration level according to ISO 10816 part 1 and ISO 10816 part 3.
Vibration of the bearing frame during continuous operation according to ISO 10816 part 1 and 3.

2.5 Material design

2.5.1 Turbine

2.5.2 Oil supply

2.5.3 Condensing plant

2.6.2 Pipe connections

All pipe connections are designed according to DIN/EN standards

2.6.3 Weights (approximate)

3. Technical description

3.1 Turbine

The condensing turbine with steam extraction in the design with one cylinder and one outlet, one active stage and multi-stage jet vanes, is designed for high efficiency and maximum reliability. The turbine is connected to the generator by means of a gearbox.

3.1.1 Control valve body

The high pressure control valve body is welded to the top of the cylinder. It is equipped with an emergency braking valve, a steam filter and control valves. The steam filter is located in the emergency brake valve. The steam filter prevents mechanical particles from entering the turbine. Its second effect is to minimize vortex steam flows and therefore reduce the vibration of the valve spools.

The emergency brake valve is designed as a diffuser valve with a pilot valve. The design of the control valve makes it possible to operate without load at full speed (to drive the generator). The emergency brake valve is actuated by an oil-hydraulic servomotor controlled by the turbine control system. Thus, it becomes possible to control the operation of the turbine by means of an emergency braking valve.

After passing through the emergency brake valve, the steam passes through the control valves.

Control valves are designed as diffuser valves and are driven by oil-hydraulic servomotors.

During start-up, the control valves are fully open and the steam flow is controlled by the emergency brake valve. This allows you to use full start, in which steam is supplied simultaneously to all nozzle boxes. This start-up mode makes it possible to simultaneously heat the steam collector and nozzle boxes. Therefore, thermal stress due to temperature differences will be minimized and start-up time will be shortened.

3.1.2 Nozzle boxes

The nozzle box has a horizontal parting line, and the parts are bolted together. The box is divided into nozzle groups. Each group is supplied with steam from a separate control valve. During turbine load changes, the nozzle box sections are subject to large temperature fluctuations, which is the cause of the thermal load. To minimize these loads, the nozzle boxes are inserted into the cylinder without expansion.

3.1.3 Cylinder

The cylinder has a horizontal parting line, forming a base and a cover. They are bolted together with cylinder connecting bolts. At the top of the cylinder there is a control valve body, at the bottom there is a nozzle for controlled and uncontrolled extraction of steam and outlet steam. In the center there is a flange on two parts for the connecting bolts of the cylinder. Support brackets are built into these flanges. The back of the cylinder is divided radially and bolted.

The outlet part stands on two supports with base plates on the foundation. These rear bearings serve as a fixed point of support for the turbine.

The casing base is connected to the bearing frame by means of bolts, which maintain the correct axial and transverse position of the turbine casing with a longitudinal key between the bearing frame and the base plate. The bearing frame is free to slide axially on the baseplate, but is kept from moving laterally by an axial key located on the longitudinal center line.

3.1.4 Rotor

The turbine rotor is made from a single piece of forged alloy steel that has been heat treated and pre-machined. After pre-machining, the last heat treatment session is carried out and a heat resistance test is performed. After that, the final machining is performed. The labyrinth seals will be inserted into the balancing piston and gland seals part. At the rear there is a clutch for power transmission. Balancing is done when the rotor is fully machined, bladed and assembled.

3.1.5 Turbine blade kit

A set of blades forms a passage for steam in the turbine. They consist of fixed parts (guide vanes) and rotating parts (rotor blades). The nozzles for the first stage are inserted into the nozzle boxes and give partial access to the control stage. The guide vanes are inserted into the blade holders, the rotor blades into the rotor. Rotating and stationary parts are separated by appropriate gaps.

3.1.6 Balance piston

The balancing piston consists of a fixed part and a rotating part. The rotating part of the balancing piston enters the rotor and is designed to reduce the axial forces of the turbine blades to low values. The remaining axial load is carried by the thrust bearing under all operating conditions. The fixed part has a horizontal parting line and is bolted together. The balancing piston is equipped with labyrinth seals, detailed in the Stuffing box section. Steam leaks that pass the balance piston return to lower pressure areas in the turbine casing.

3.1.7 Seals

Labyrinth type seals provide tightness where the rotor shaft passes through the cylinder. Sealing strips are inserted into the rotating and stationary parts. The seal design makes them easy to replace. To replace the balancing piston and internal labyrinth seals, the body must be lifted.

3.1.8 Bearing racks

The bearing pedestals are at the ends of the cylinder and have a horizontal split. The cover is bolted to the base and can be easily removed for service (no need to open the cylinder or remove the body insulation). The front bearing frame is equipped with a thrust bearing and plain bearing, a gearbox for the main oil pump and sensors for axial displacement, shaft vibration, bearing temperature and speed. The fixed rear bearing frame is equipped with a plain bearing, a turning device and sensors for shaft vibration and bearing temperature.

3.1.9 Bearings

Plain bearings - split type are made of anti-friction metal (white metal) with a steel shell. The design of the valve seat makes it easy to center the bearing by inserting inserts of the desired thickness under four adjusting wedges located at 90 degrees from each other.

The rotor is attached to the front bearing pedestal with a self-aligning double-acting segmented thrust bearing suitable for both directions of rotation and thrust. Each bearing will be supplied with oil for lubrication and cooling.

3.1.10 Turbine insulation

Parts of the turbine operating at high temperature steam will be covered with insulating material. The insulation is made of fiberglass mats and filled with mineral wool (no asbestos). Two-layer insulation of the body is provided, the outer layer is covered with aluminum foil.

3.2 Transfer

3.2.1 Reducer

The gearbox is located between the turbine and the driven mechanism. It is provided to reduce the speed of the turbine to the speed of the driven machine. Design - single-stage horizontal with axial displacement and herringbone gear. The drive and driven gear shafts are equipped with two plain bearings each and white metal bushings. Lubrication comes from a common oil supply.

The body has a horizontal split, the cover is bolted to the bottom.

3.2.2 High speed clutch

It is located between the turbine and the gearbox. Lubrication comes from the total oil supply to the turbine. The coupling is provided with an oil-tight cover. The return oil flows to the turbine bearing pedestals.

3.2.3 Turning device

The turning device is driven by an AC motor. It will be in operation after the turbine has stopped and must remain in operation until the turbine is started or when the turbine is cooled down.

To ensure the best balance of rotor cooling, the barring device is used during slow rotation of the rotor. This prevents the rotor from bending during cooling. Also, when the barring device is in operation, flexing of the cylinder is minimized by ventilation in the turbine.

It is equipped with devices that allow manual control only when the turbine is at zero speed, and switches to automatic mode when the speed increases.

3.3 Steam seal system

To prevent air from the atmosphere from entering the low-pressure part of the turbine (vacuum zone), sealing steam is supplied to the seal. The seal steam is controlled by control valves, one per seal. Medium or low pressure steam will be used as primary steam.

One part of the sealing vapor passes through the inside of the seal and flows towards the condenser. The rest of the seal vapor passes through the outer part of the seal and flows towards the seal vapor condenser.

The steam and air after the turbine seals is directed to the second stage of the steam ejector-condenser or the surface horizontal condenser of the sealing steam using an exhaust fan. Steam leaks from the turbine seals are directed into the shroud and condensed by the coolant. The condensate is drained to the main condenser. Air leaks, including small amounts of steam, are vented to the atmosphere.

3.4 Oil system

The oil system is a combined system of lubricating, working and control oil. It consists of oil tank, pumps, filters, coolers, pressure control valves, purifier and connecting piping.

3.4.1 Oil pumps

The main oil pump is driven by an AC motor and is located on the oil tank.

An auxiliary oil pump (driven by an AC motor), also located on the oil tank, automatically takes over the function of the main oil pump when needed. This auxiliary oil pump starts automatically when the bearing oil pressure drops.

If the auxiliary oil pump fails or cannot start, the emergency oil pump starts. The emergency oil pump is designed to supply lubricating oil during the shutdown of the turbine generator set, as well as during the cooling of the turbine rotor.

Part of the lubricating oil is supplied by booster pumps (2 x 100%). They provide the necessary pressure for the operating oil and control oil systems. The working oil is used to operate the control valves and the emergency brake valve with servomotors.

3.4.2 Oil pressure control

The lubricating oil pressure is controlled by a separate control valve. Control valves operate on bypass. The lube oil pressure is controlled by a lube oil bypass to the oil tank. The operating oil is controlled by the regulating oil pump.

3.4.3 Lifting oil system

The lift oil pump, driven by an AC motor, is used during barring operation and during start-up and shutdown of the turbine generator set to lift the rotor to minimize friction in the generator rotor bearings.

3.4.4 Oil tank

The oil tank is located next to the turbine. It is designed for the entire volume of oil for lubrication and control of the entire turbine unit. It is equipped with an air separation device. Oil pumps and a steam exhaust fan are mounted on the tank cover. The fan maintains a slight negative pressure in the drain system and in the oil tank.

3.4.5 Oil coolers

The system is equipped with two identical oil coolers, each with a capacity of 100%. Switching between coolers during operation takes place with the help of three-way valves.

The idle cooler can be drained and cleaned or replaced while the turbine is running.

3.4.6 Oil filter

The system is equipped with two identical oil filters for control and lubricating oil, each with a capacity of 100%. Switching between filters during operation takes place with the help of three-way valves.

A filter that is not in operation can be cleaned or replaced while the turbine is running.

3.4.7 Oil line

The connecting pipeline includes pipes between various units of the oil system. Lube oil line to turbine and generator included with oil return lines to oil tank. A connecting oil line is also provided for control purposes (pilot and operating oil lines), including return lines to the oil tank.

The connecting pipeline is made of carbon steel, the pipeline after the filter is made of stainless steel.

3.5 Surface condenser

3.5.1 General description

Surface type water cooled condenser with steam inlet at the top. The condenser can condense all of the steam from the turbine under any envisaged operating conditions.

The condenser is designed for low steam velocity over the entire surface of the pipe. The distribution of steam to all parts of the cooling surface guarantees a high degree of heat transfer from steam to cooling water and the highest possible vacuum for a given quantity and temperature of cooling water.

Condensate, flowing down from pipes, allows to achieve a good degree of condensate deaeration.

Air and non-condensable vapors in the condenser may come into contact with the pipes in the coldest part of the condenser. The maximum cooling of these gases allows them to be collected and removed from the condenser by a vacuum pump.

The condensate collector is welded to the bottom of the condenser casing. Its function is to collect and accumulate condensate.

3.5.2 Condenser shell

The condenser jacket is designed for vacuum and withstands an internal pressure of 1 barg. Suitable openings are provided for the intake of steam from the turbine and for the removal of air and condensate. Pipe plates are attached to the ends of the casing. Between the tube sheets in the shell are several support plates to support and minimize tube vibration.

The condenser tubes are attached to the tube sheet on both sides.

The condenser is placed on a suitable foundation and connected to the turbine exhaust pipe.

3.5.3 Water jacket

Water jackets are welded to both ends of the casing.

In the water jackets there are connections for cooling water and corresponding manholes with covers.

Internal coating prevents corrosion.

3.5.4 Condensate pumps

Condensate pumps are provided, each with a capacity of 100%. They are located below the condenser.

Type of pumps - centrifugal horizontal pumps. They have an end connector and a radial impeller. Execution - direct-flow single-stage. A shaft seal is provided with a seal water connection to prevent air from entering the condensate system (vacuum zone).

Connections according to DIN standard.

The pumps are equipped with filters on the suction side. Isolation valves are provided on the suction side (before the filter) and on the discharge side. The pumps are driven by an AC motor and mounted on a base plate.

3.5.5 Air ejectors

Two two-stage steam driven air ejectors are provided to remove non-condensable gases from the condenser shell. Each ejector is a two-stage type and is mounted on the casing of the ejector-condenser, which condenses the steam of two stages. The condensate is returned to the main condenser. The pipes are designed to transfer 100% of the condensate extracted from the main condenser.

An additional starting ejector is provided for starting. The starting ejector is single-stage, non-condensing type. The ejector has an outlet to the atmosphere.

3.5.6 Condensate level control system

The condensate level control system regulates a constant level in the condenser.

It consists of a level controller, an emission control valve and a recirculation valve. If the condensate flow is less than the required minimum flow of the condensate pumps or the minimum required quantity for the ejector-condenser and seal vapor condenser, the recirculation valve opens and the blowout control valve closes.

Controller - electronic type or DCS. The control valves (ejection and recirculation control valve) can be actuated by electric or pneumatic actuators.

3.5.7 Connecting pipes

The connecting piping includes condenser condensate drain pipes, condenser air vent pipes to ejector, seal water (condensate) pipes for seals in the vacuum zone (condensate valves and pumps) and an emergency outlet pipe with a rupture disc. All connecting pipes are made of carbon steel.

4. Turbine control and protection system

4.1 Operation and control (visual)

4.1.1 Operator station in the turbine control center

One control panel
19" touch screen, resolution 1280x1024
USB interface
24 V DC
processor 533 MHZ FSB, 2 MB SLC
memory 1 GB DDR266 SDRAM (1x1 GB)
DVD-ROM Windows XP Pro MUI
DDR SDRAM (2x128 MB) dual channel, 1.44 MB
FDD+DVD ROM, Windows 2000 already installed
1 PC. communication module CP 1613 Ethernet
1 PC. Microsoft small office
1 PC. 19” flat screen, terminal with keypad for receiving/transmitting data
mouse to install

4.1.2 Imaging software

1 PC. Software WIN CC V6.0 + SP2
license to use

4.1.3 Visualization of specialized software

Our offer includes the following monitoring displays for the operation and control of the turbine generator and auxiliary equipment, for example:

overview
steam system
turbine control
lube oil system
control oil system
visualization and monitoring of bearing temperatures
generator, automatic voltage regulator, protection and synchronization
functional groups including
growth curves, archive function for measurements, event log, alarms with short-term and long-term storage function

4.2 Turbine closed circuit control and protection

4.2.1 PLC hardware

As an automation system, a PLC for open loop control, closed loop control and protection is offered with the following modules:

1 PC. rack
1 PC. power supply PS 405 (10 A) with buffer battery
1 PC. CPU 414-3 with EPROM 1MB
1 PC. industrial Ethernet communication module CP 443-1
1 PC. interface module IF 964 DP

4.2.1.1 Turbine PLC hardware

For speed control, a PLC with the following modules is provided:

1 PC. rack
1 PC. power supply PS 307 (2A)
1 PC. CPU-317-2DP
1 PC. analog input (8 AI)
1 PC. digital input/output module (8DI/8DO)
2 pcs. analog output modules (4AO)
1 PC. micro memory card
1 PC. speed input card / 8 channels

Local I/O - Peripherals:

6 pcs. Serial interface (Profibus DP)
6 pcs. digital input modules (16 DI each module)
6 pcs. digital input modules (32 DI)
2 pcs. digital output modules (32 DO each module)
13 pcs. analog input modules (8 AI each module)
7 pcs. analog input modules pt 100 (8 AI)
2 pcs. analog output modules (8 AO each module)
5 pieces. racks
front plugs

4.2.1 Dedicated PLC software

The specialized software for turbogenerator and synchronization consists of:

turbine protection, turbine closed loop control:
speed/frequency control
turbine protection, for example:
vibration
lube oil temperature/pressure
back pressure
other
open loop control of the following auxiliary drives:
auxiliary oil pump
emergency lube oil pump
oil vapor exhaust fan
heating the generator during inactivity
rotary device
sealing steam condenser fan
start and stop function groups
functional group of lubricating oil system
rotary device functional group
turbine functional group

4.2.2 Speed measurement and overspeed protection

4.2.2.1 Overspeed protection / speed control

The 2 of 3 overspeed protection device includes the following equipment:

1 PC. stand MMS 6352 19”
1 PC. connection panel MMS 6351/10
3 pcs. speed controller MMS 6350/D
6 pcs. connection cable 3 m MMS 6360
6 pcs. connection block MMS 6361 25pol Sub D
3 pcs. sleeves for sensors including fixing nuts (stainless steel)
3 pcs. speed sensors

4.3 Generator protection and synchronization

4.3.1 Generator protection

1 PC. multifunction generator protection relay

The following protection functions can be implemented:

differential protection
overcurrent protection
earth fault protection of the rotor
stator earth fault protection (protection range 95%/Uo)
reverse power protection
protection against underexcitation
overload protection
overvoltage protection (2 steps)
undervoltage protection (2 steps)
underfrequency protection
overexcitation protection
unbalanced load protection

Implemented functions are discussed at further stages of the project.

1 PC. connection device for rotor earth fault protection 7XR61
Turbine emergency stop signal and generator circuit breaker opening and shutdown excitation are hardwired

Additional inputs/outputs are provided:

1 input for emergency stop of the stator winding at high temperature
3 inputs for external signals (floating)
4 programmable emergency stop outputs
data transfer to the main PLC via Profibus DP

4.3.2 Automatic voltage regulation cabinet

4.3.3 Synchronization

1 PC. an automatic synchronization device is installed on all equipment for manual synchronization:

dual voltmeter
double frequency counter
switches for breakers
auto/manual selection
start/stop synchronization
synchroscope

4.4 Turbine and generator control cabinets

4.4.1 Turbine control cabinet

Our scope of supply includes:

1 PC. turbine control cabinet, color RAL 7032
Dimensions W x D x H = 2000 x 600 x 2200 mm including base frame 200 mm
Protection class IP41

Included:

bottom cover steel plate
cable ducts, profile rails and cable fixing rails
for incoming / outgoing cables
cabinet lighting, 110V AC sockets
measuring the internal temperature in the turbine control cabinet
1 PC. emergency stop relay
2 fans

The overspeed and speed measuring device are mounted on the swing frame. The PLCs are mounted on a frame.
Also separately mounted on the frame and separately supplied with power to control and protect the bypass.

Power supply 220 VAC for lights/fans and also 24 VDC for turbine control cabinet supplied by others

4.4.2 Local cabinet for distributed I/O

One local closet
color RAL7032
Dimensions W x D x H = 1200 x 600 x 2200 mm including base frame 200 mm
Protection class IP41
Included:
bottom cover steel plate,

cabinet lighting, 220 V AC sockets
measuring the internal temperature in the turbine control cabinet
1 fan

4.4.3 Generator control cabinet

1 PC. control cabinet color RAL7032
Dimensions W x D x H = 1600 x 800 x 2200 mm including 200 mm base frame, IP41 protection, including:
bottom cover steel plate
cable ducts, profile rails and cable fixing rails for incoming/outgoing cables
cabinet lighting, 110V AC sockets
measuring the internal temperature in the control cabinet

The following parts are installed on the swing frame
generator protection relays
synchronization relay
2 current/voltage transformers for exciter voltage and current
all manual timing equipment

One device for communication to the PLC via the Profibus bus is mounted on the rack
One-line electrical network diagram on the front of the cabinet

4.5 Factory acceptance test

An acceptance test will be carried out in the shop before shipment.
All incoming and outgoing signals will be fully tested from clamps to imaging.

5. List of electrical consumers

	Quantity	Power (kW / installation)	Voltage (V)	Frequency Hz)	Reserve	Working
Main oil pump	1	11	400	50	1
Auxiliary oil pump	1	11	400	50	1	1
Oil regulating pump	2	15	400	50		1
Emergency oil pump	1	3	110	fast. current	1
High pressure pump (hydraulic lift oil)	1	15	400	50	1
fan oil mist	1	0.18	400	50		1
Oil temperature control valve	1	0.18	230	50		1
Rotor swivel device	1	22	400	50	1
Solenoid valve, selection	2	0.1	230	50		2
Instrumentation	1	2.5	230	50		1
Generator protection and excitation	1	6	230	50		1
Generator heater	1	10	230	50	1
Condensate pump	2	30	400	50	1	1
Sealing steam condensate fan	1	5.5	400	50		1
Condensate level control valve	1	0.18	230	50		1
Condensate circulation valve	1	0.18	230	50		1

1 emergency braking valve at the turbine inlet 1 flow straightener built into the braking valve 1 control valves 1 set turning device 1 base frame for turbine and gearbox 1 set anchor bolts and nuts 1 set turbine insulating material 1 set thermal insulation for turbine 1 set

7.2 Lubrication system and governor oil

One set of lubrication system and governor oil consists of:

oil tank	1
main oil pump (driven by AC motor)	1
auxiliary oil pump (driven by AC motor)	1
control oil pump (driven by AC motor)	2
emergency oil pump (driven by DC motor)	1
oil cooler (cooling water filter less than 500 microns)	2
oil filter	2
oil temperature control valve	1
oil pipeline from the oil tank to the turbine, gearbox and generator and back	1 set
oil pressure control valve	1
oil piping and valves	1 set
exhauster driven by an alternating current motor	1
electric oil heater	1

7.3 Reducer

7.4 Condenser

One condensing device consists of:

turbine control system including speed control

shell and tube surface condenser	1
two-stage steam jet air ejector	1
starting ejector	1
rupture disk	1
condensate level control system including level sensors, level control valve, minimum flow valve	1 set
condensate pump including AC motor, base plates with anchor bolts and couplings	2 sets
piping including necessary valves	1 set
connecting piece turbine-main condenser	1 set
shaft vibration measurement for 6 bearings	1 set
measurement of the axial position of the rotor	1 set
turbine protection interlock system	1
required local instrumentation	1 set
local sensors and signaling devices, mounted on a rack	1 set
local sensors and signaling devices for installation outside the scope of delivery, as separate parts	1 set
special cables for turbine electronic control system	1 set

All modules supplied by the seller are internally wired and tested down to the terminal boxes.

7.7 Generator

7.8 Turbine generator foundation

7.9 Services

installation supervision (at rates per day)
commissioning (according to tariffs per day)
trial run (2 weeks, 1 shift) (per day rates)
training of the buyer's personnel during commissioning and trial run

7.10 Exclusions from the scope of delivery

The following main components, materials and services are not included in the turbine seller's scope of supply:

design, layout, manufacture, supply of parts and services not specified in this document
working drawings
stability analysis for the introduction of the generator into production
other coding systems in the enterprise
construction calculations, construction works, cement materials
support structures, platforms, ladders, heater enclosures and other equipment
floor covers, walkways
corrugated sheet walkways for floor openings, trenches and channels
lighting and communication systems, air conditioning equipment
switchgear, motor control cabinet, low-voltage network, cables and cable ducts
220VAC UPS, Battery, Charger and Panels
grounding system
fire extinguishing equipment
cranes
mating flanges, bolts, nuts, gaskets at all end points of delivery
cooling water system
heaters, deaerator, feed water lines, drain tank, bypass system
thermal insulation for pipes, conduits and accessories
first oil filling, oil separator
noise protection hood
no load test on incoming oil at the factory, first oil filling, oil cleaner
standard tools and welding equipment for site installation and maintenance
spare parts (except spare parts for commissioning) (option)
test turbine without load in the workshop
paint materials on site
storage, preparation for operation in the winter
installation
commissioning, trial operation
supplier training course
third party verification
performance test, specially calibrated performance test tools

7.11 Delivery limits

base plates for supplied equipment
nozzles at the inlet / outlet of the turbine for live steam and steam extraction
inlet/outlet flanges at check valve
cooling water inlet/outlet flanges at condenser, oil cooler and generator cooler
condensate outlet after the control valve in the area of the turbine base
outlet fan - sealing steam condenser
output exhauster
terminals for electrical equipment / instrumentation at the control cabinet of the turbine / generator
electrical/instrument terminals at local junction boxes
terminals for portable instrumentation
terminals for electric motors, drives, solenoid valves
terminals 10.5 kV for generator

From tens of thousands of revolutions per minute (for synchronous turbogenerators with excitation from permanent magnets "NPK "Energodvizhenie") to 3000, 1500 rpm (for synchronous turbogenerators with excitation of the rotor). Mechanical energy from the turbine is converted into electrical energy by means of a rotating magnetic field of the rotor in stator The rotor field, which is created either by permanent magnets installed on the rotor, or by a direct voltage current flowing in the copper winding of the rotor, leads to the appearance of a three-phase alternating voltage and current in the stator windings.The voltage and current on the stator are greater, the stronger the rotor field, i.e. more current flowing in the rotor windings.In synchronous turbogenerators with external excitation, the voltage and current in the rotor windings are created by a thyristor excitation system or an exciter - a small generator on the turbogenerator shaft.Turbogenerators have a cylindrical rotor mounted on two plain bearings, in a simplified form it resembles enlarged car alternator. 2-pole (3000 rpm), 4-pole (1500 rpm as at Balakovo NPP), and multi-pole machines are produced, depending on the places of operation and the requirements of the Customer. According to the methods of cooling the turbogenerator windings, they are distinguished: with liquid cooling through the stator jacket; with liquid direct cooling of windings; air-cooled; with hydrogen cooling (more often used at nuclear power plants).

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One of the founders of ABB, Charles Brown, built the first turbogenerator in 1901. It was a 100 kVA 6-pole generator.

Types of turbogenerators

Turbogenerator design

Generator rotor excitation

October 24, 2012

Electrical energy has long been part of our lives. Even the Greek philosopher Thales discovered in the 7th century BC that amber, worn on wool, begins to attract objects. But for a long time no one paid attention to this fact. Only in 1600 did the term “Electricity” first appear, and in 1650 Otto von Guericke created an electrostatic machine in the form of a sulfur ball mounted on a metal rod, which made it possible to observe not only the attraction effect, but also the repulsion effect. It was the first simple electrostatic machine.

Many years have passed since then, but even today, in a world filled with terabytes of information, when you can find out everything that interests you, for many it remains a mystery how electricity is produced, how it is delivered to our home, office, enterprise ...

Let's take a look at these processes in a few parts.

Part I. Generation of electrical energy.

Where does electrical energy come from? This energy appears from other types of energy - thermal, mechanical, nuclear, chemical and many others. On an industrial scale, electrical energy is obtained at power plants. Consider only the most common types of power plants.

1) Thermal power plants. Today, they can be combined by one term - GRES (State District Power Plant). Of course, today this term has lost its original meaning, but it has not gone into eternity, but has remained with us.

Thermal power plants are divided into several subtypes:

BUT) A condensing power plant (CPP) is a thermal power plant that produces only electrical energy; this type of power plant owes its name to the peculiarities of the principle of operation.

Principle of operation: Air and fuel (gaseous, liquid or solid) are supplied to the boiler by means of pumps. It turns out a fuel-air mixture that burns in the boiler furnace, releasing a huge amount of heat. In this case, water passes through the pipe system, which is located inside the boiler. The released heat is transferred to this water, while its temperature rises and is brought to a boil. The steam that was received in the boiler goes back to the boiler to superheat it above the boiling point of water (at a given pressure), then it enters the steam turbine through the steam pipelines, in which the steam does work. As it expands, its temperature and pressure decrease. Thus, the potential energy of the steam is transferred to the turbine, which means it is converted into kinetic energy. The turbine, in turn, drives the rotor of a three-phase alternator, which is located on the same shaft as the turbine and produces energy.

Let's take a closer look at some elements of the IES.

Steam turbine.

The flow of water vapor enters through the guide vanes on the curvilinear blades fixed around the circumference of the rotor, and, acting on them, causes the rotor to rotate. Between the rows of shoulder blades, as you can see, there are gaps. They are there because this rotor is removed from the housing. Rows of blades are also built into the body, but they are stationary and serve to create the desired angle of incidence of steam on the moving blades.

Condensing steam turbines are used to convert the maximum possible part of the heat of steam into mechanical work. They work with the release (exhaust) of the exhaust steam into the condenser, which is maintained under vacuum.

A turbine and a generator that are on the same shaft are called a turbogenerator. Three-phase alternator (synchronous machine).

It consists of:

Which increases the voltage to a standard value (35-110-220-330-500-750 kV). In this case, the current is significantly reduced (for example, with an increase in voltage by 2 times, the current decreases by 4 times), which makes it possible to transmit power over long distances. It should be noted that when we talk about voltage class, we mean linear (phase-to-phase) voltage.

The active power that the generator produces is regulated by changing the amount of energy carrier, while changing the current in the rotor winding. To increase the output active power, it is necessary to increase the steam supply to the turbine, while the current in the rotor winding will increase. It should not be forgotten that the generator is synchronous, which means that its frequency is always equal to the frequency of the current in the power system, and changing the parameters of the energy carrier will not affect the frequency of its rotation.

In addition, the generator also generates reactive power. It can be used to regulate the output voltage within small limits (i.e. it is not the main means of voltage regulation in the power system). It works in this way. When the rotor winding is overexcited, i.e. when the voltage on the rotor rises above the nominal value, the "surplus" of reactive power is supplied to the power system, and when the rotor winding is underexcited, the reactive power is consumed by the generator.

Thus, in alternating current, we are talking about apparent power (measured in volt-amperes - VA), which is equal to the square root of the sum of active (measured in watts - W) and reactive (measured in reactive volt-amperes - VAR) power.

The water in the reservoir serves to remove heat from the condenser. However, spray pools are often used for this purpose.

or cooling towers. Cooling towers are tower Fig. 8

or fan Fig.9

Cooling towers are arranged in almost the same way as with the only difference that the water flows down the radiators, transfers heat to them, and they are already cooled by the forced air. In this case, part of the water evaporates and is carried away into the atmosphere.
The efficiency of such a power plant does not exceed 30%.

B) Gas turbine power plant.

At a gas turbine power plant, the turbogenerator is driven not by steam, but directly by gases produced by the combustion of fuel. In this case, only natural gas can be used, otherwise the turbine will quickly come out of standstill due to its pollution with combustion products. Efficiency at maximum load 25-33%

Much higher efficiency (up to 60%) can be obtained by combining steam and gas cycles. Such installations are called combined-cycle plants. Instead of a conventional boiler, they have a waste heat boiler that does not have its own burners. It receives heat from the exhaust gas turbine. At present, CCGTs are being actively introduced into our lives, but so far there are not many of them in Russia.

IN) Combined heat and power plants (became an integral part of large cities for a very long time). Fig.11

CHPP is structurally arranged as a condensing power plant (CPP). The peculiarity of this type of power plant is that it can simultaneously generate both thermal and electrical energy. Depending on the type of steam turbine, there are various methods of steam extraction, which allow you to take steam from it with different parameters. In this case, part of the steam or all of the steam (depending on the type of turbine) enters the network heater, gives it heat and condenses there. Cogeneration turbines allow you to adjust the amount of steam for thermal or industrial needs, which allows CHP to operate in several load modes:

thermal - the generation of electrical energy is completely dependent on the generation of steam for industrial or heating needs.

electrical - the electrical load is independent of the thermal. In addition, CHPs can operate in a fully condensing mode. This may be required, for example, in case of a sharp shortage of active power in summer. Such a regime is unfavorable for CHPPs, because efficiency drops significantly.

Simultaneous production of electricity and heat (cogeneration) is a profitable process in which the efficiency of the station is significantly increased. So, for example, the calculated efficiency of a CPP is a maximum of 30%, and for a CHP it is about 80%. In addition, cogeneration makes it possible to reduce idle thermal emissions, which has a positive effect on the ecology of the area in which the CHPP is located (compared to if there was a CPP of the same capacity).

Let's take a closer look at the steam turbine.

Cogeneration steam turbines include turbines with:

backpressure;

Adjustable steam extraction;

Selection and backpressure.

Turbines with backpressure work with steam exhaust not into the condenser, as in IES, but into the network heater, that is, all the steam that has gone through the turbine goes to heating needs. The design of such turbines has a significant drawback: the electrical load schedule is completely dependent on the heat load schedule, that is, such devices cannot take part in the operational regulation of the current frequency in the power system.

In turbines having a controlled steam extraction, it is extracted in the required amount in the intermediate stages, while choosing such stages for steam extraction, which are suitable in this case. This type of turbine is independent of the thermal load and the regulation of the output active power can be adjusted to a greater extent than in a backpressure CHP plant.

Extraction and backpressure turbines combine the functions of the first two types of turbines.

Cogeneration turbines of CHPPs are not always capable of changing the heat load in a short period of time. To cover load peaks, and sometimes to increase electric power by transferring turbines to a condensing mode, peak hot water boilers are installed at the CHPP.

2) Nuclear power plants.

There are currently 3 types of reactor plants in Russia. The general principle of their operation is approximately similar to the operation of IES (in the old days, nuclear power plants were called GRES). The fundamental difference is only that thermal energy is obtained not in fossil fuel boilers, but in nuclear reactors.

Consider the two most common types of reactors in Russia.

1) RBMK reactor.

A distinctive feature of this reactor is that the steam for rotating the turbine is produced directly in the reactor core.

RBMK core. Fig.13

consists of vertical graphite columns in which there are longitudinal holes, with pipes made of zirconium alloy and stainless steel inserted into them. Graphite acts as a neutron moderator. All channels are divided into fuel and CPS channels (control and protection system). They have different cooling circuits. A cassette (FA - fuel assembly) with rods (TVEL - fuel element) is inserted into the fuel channels, inside of which there are uranium pellets in a sealed shell. It is clear that it is from them that they receive thermal energy, which is transferred to a heat carrier continuously circulating from bottom to top under high pressure - ordinary, but very well purified from impurities, water.

Water, passing through the fuel channels, partially evaporates, the steam-water mixture flows from all individual fuel channels into 2 separator drums, where the separation (separation) of steam from water takes place. Water again goes into the reactor with the help of circulation pumps (out of 4 in total per loop), and steam goes through steam pipelines to 2 turbines. Then the steam condenses in the condenser, turns into water, which goes back to the reactor.

The thermal power of the reactor is controlled only by boron neutron absorber rods that move in the CPS channels. The water cooling these channels goes from top to bottom.

As you can see, I have never mentioned the reactor vessel yet. The fact is that in fact the RBMK does not have a hull. The active zone, which I just told you about, is placed in a concrete shaft, on top it is closed with a lid weighing 2000 tons.

The figure shows the upper biological protection of the reactor. But you should not expect that by lifting one of the blocks, you can see the yellow-green vent of the active zone, no. The cover itself is located much lower, and above it, in the space up to the upper biological protection, there is a gap for communication channels and completely removed absorber rods.

Space is left between the graphite columns for thermal expansion of the graphite. A mixture of nitrogen and helium gases circulates in this space. According to its composition, the tightness of the fuel channels is judged. The RBMK core is designed to break no more than 5 channels, if more is depressurized, the reactor cover will come off and the remaining channels will open. Such a development of events will cause a repetition of the Chernobyl tragedy (here I mean not the man-made disaster itself, but its consequences).

Consider the advantages of RBMK:

— Thanks to the channel-by-channel regulation of thermal power, it is possible to change fuel assemblies without stopping the reactor. Every day, usually, they change several assemblies.

—Low pressure in the MPC (multiple forced circulation circuit), which contributes to a milder course of accidents associated with its depressurization.

— Absence of a reactor pressure vessel that is difficult to manufacture.

Consider the cons of RBMK:

—During operation, numerous miscalculations were found in the geometry of the core, which cannot be completely eliminated at the operating power units of the 1st and 2nd generations (Leningrad, Kursk, Chernobyl, Smolensk). RBMK power units of the 3rd generation (it is the only one - at the 3rd power unit of the Smolensk NPP) is devoid of these shortcomings.

— One-loop reactor. That is, the turbines are rotated by steam obtained directly in the reactor. This means that it contains radioactive components. If the turbine is depressurized (and this happened at the Chernobyl nuclear power plant in 1993), its repair will be greatly complicated, and perhaps even impossible.

— The service life of the reactor is determined by the service life of graphite (30-40 years). Then comes its degradation, manifested in its swelling. This process is already causing serious concern at the oldest power unit RBMK Leningrad-1, built in 1973 (it is already 39 years old). The most likely way out of the situation is to muffle the nth number of channels to reduce the thermal expansion of graphite.

— Graphite moderator is a combustible material.

— Due to the huge number of shut-off valves, the reactor is difficult to manage.

- On the 1st and 2nd generations, there is instability when operating at low powers.

In general, we can say that the RBMK is a good reactor for its time. At present, a decision has been made not to build power units with this type of reactors.

2) VVER reactor.

RBMK is currently being replaced by VVER. It has significant advantages over RBMK.

The core is completely located in a very strong case, which is manufactured at the plant and brought by rail, and then by road to the power unit under construction in a completely finished form. The moderator is clean water under pressure. The reactor consists of 2 circuits: the primary circuit water under high pressure cools the fuel assemblies, transferring heat to the 2nd circuit using a steam generator (acts as a heat exchanger between 2 isolated circuits). In it, the water of the second circuit boils, turns into steam and goes to the turbine. In the primary circuit, the water does not boil, as it is under very high pressure. The exhaust steam condenses in the condenser and goes back to the steam generator. The two-circuit scheme has significant advantages compared to the single-circuit one:

The steam going to the turbine is not radioactive.

The power of the reactor can be controlled not only by absorber rods, but also by a solution of boric acid, which makes the reactor more stable.

The elements of the primary circuit are located very close to each other, so they can be placed in a common containment. In case of breaks in the primary circuit, radioactive elements will enter the containment and will not be released into the environment. In addition, the containment protects the reactor from external influences (for example, from the fall of a small aircraft or an explosion outside the station perimeter).

The reactor is not difficult to manage.

There are also disadvantages:

—Unlike RBMK, the fuel cannot be changed while the reactor is running, because it is located in a common building, and not in separate channels, as in the RBMK. The fuel refueling time usually coincides with the maintenance time, which reduces the impact of this factor on the ICF (installed power factor).

— The primary circuit is under high pressure, which could potentially cause a larger depressurization accident than RBMK.

— The reactor vessel is very difficult to transport from the manufacturing plant to the NPP construction site.

Well, we have considered the work of thermal power plants, now we will consider the work

The principle of operation of a hydroelectric power station is quite simple. A chain of hydraulic structures provides the necessary pressure of water flowing to the blades of a hydraulic turbine, which drives generators that generate electricity.

The necessary pressure of water is formed through the construction of a dam, and as a result of the concentration of the river in a certain place, or by derivation - the natural flow of water. In some cases, both a dam and a derivation are used together to obtain the necessary water pressure. HPPs have a very high flexibility of generated power, as well as a low cost of generated electricity. This feature of the hydroelectric power station led to the creation of another type of power plant - the pumped storage power plant. Such stations are able to accumulate the generated electricity, and put it into use at times of peak loads. The principle of operation of such power plants is as follows: during certain periods (usually at night), the HPP hydroelectric units operate as pumps, consuming electrical energy from the power system, and pump water into specially equipped upper pools. When there is a demand (during load peaks), the water from them enters the pressure pipeline and drives the turbines. PSPPs perform an extremely important function in the power system (frequency control), but they are not widely used in our country, because. As a result, they consume more power than they give out. That is, a station of this type is unprofitable for the owner. For example, at the Zagorskaya PSP, the power of hydro generators in the generator mode is 1200 MW, and in the pump mode - 1320 MW. However, this type of station is best suited for a rapid increase or decrease in generated power, so it is advantageous to build them near, for example, nuclear power plants, since the latter operate in the base mode.

We have looked at how electrical energy is produced. It's time to ask yourself a serious question: "And what type of stations best meets all modern requirements for reliability, environmental friendliness, and besides this, will it also be distinguished by low energy costs?" Everyone will answer this question differently. Here's my "best of the best" list.

1) CHPP on natural gas. The efficiency of such stations is very high, and the cost of fuel is also high, but natural gas is one of the “cleanest” types of fuel, and this is very important for the ecology of the city, within the boundaries of which thermal power plants are usually located.

2) HPP and PSP. The advantages over thermal plants are obvious, since this type of plant does not pollute the atmosphere and produces the “cheapest” energy, which, in addition, is a renewable resource.

3) CCGT on natural gas. The highest efficiency among thermal stations, as well as a small amount of fuel consumed, will partially solve the problem of thermal pollution of the biosphere and limited fossil fuel reserves.

4) NPP. In normal operation, a nuclear power plant emits 3-5 times less radioactive substances into the environment than a thermal power plant of the same capacity, so partial replacement of thermal power plants by nuclear power plants is fully justified.

5) GRES. Currently, such stations use natural gas as fuel. This is absolutely meaningless, since with the same success it is possible to utilize associated petroleum gas (APG) in the furnaces of the GRES or burn coal, the reserves of which are huge compared to the reserves of natural gas.

This concludes the first part of the article.

Material prepared:
student of group ES-11b SWGU Agibalov Sergey.

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How does a thermal power plant (CHP) work? Steam turbine installations of thermal power plants (TPPs) Design features of the turbogenerator

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Turbogenerator design

Generator rotor excitation

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History

Types of turbogenerators

Turbogenerator design

Generator rotor excitation