Technical characteristics of the turbine PT 80. On the operation of the steam turbine

Steam turbine type PT-60-130/13– condensing, with two adjustable steam extractions. Rated power 60,000 kW (60 MW) at 3000 rpm. The turbine is designed directly to drive an alternator type TVF-63-2 with a power of 63,000 kW, with a voltage at the generator terminals of 10,500 V, mounted on a common foundation with the turbine. The turbine is equipped with a regenerative device for heating feed water and must work with a condensing unit. When the turbine operates without controlled extractions (pure condensing mode), a load of 60 MW is allowed.

Steam turbine type PT-60-130/13 designed for the following parameters:

• fresh steam pressure in front of the automatic stop valve (ASV) 130 ata;
• fresh steam temperature before ASK 555 ºС;
• the amount of cooling water passing through the condenser (at a design temperature at the condenser inlet of 20 ºС) 8000 m/h;
• The estimated maximum steam consumption at nominal parameters is 387 t/hour.

The turbine has two adjustable steam extractions: industrial With nominal pressure 13 ata and heating with a nominal pressure of 1.2 ata. Production and heating extraction have the following pressure control limits:

• production 13+3 ata;
• heating 0.7-2.5 ata.

The turbine is a single-shaft two-cylinder unit. Cylinder high pressure has a single crown control stage and 16 pressure stages. Cylinder low pressure consists of two parts, of which the medium pressure part has a control stage and 8 pressure stages, and the low pressure part has a control stage and 3 pressure stages.

All high pressure rotor discs are forged integrally with the shaft. The first ten disks of the low-pressure rotor are forged integrally with the shaft, the remaining four disks are mounted.

The HPC and LPC rotors are connected to each other via a flexible coupling. The rotors of the LPC and the generator are connected via a rigid coupling. nRVD = 1800 rpm, nRVD = 1950 rpm.

Solid forged rotor Turbine HPC PT-60-130/13 has a relatively long front shaft end and a petal (sleeveless) labyrinth seal design. With this design of the rotor, even slight contact of the shaft with the ridges of the end or intermediate seals causes local heating and elastic deflection of the shaft, which results in vibration of the turbine, the operation of the studs of the band band, working blades, and an increase in radial clearances in the intermediate and over-band seals. Typically, rotor deflection appears in the operating speed zone of 800-1200 rpm. during turbine startup or during rotor run-out when it is stopped.

The turbine is supplied turning device, rotating the rotor at a speed of 3.4 rpm. The turning device is driven into rotation by an electric motor with a squirrel-cage rotor.

The turbine has nozzle steam distribution. Fresh steam is supplied to a free-standing steam box in which an automatic shutter is located, from where the steam flows through bypass pipes to the turbine control valves. located in steam boxes welded into the front part of the turbine cylinder. The minimum steam passage in the condenser is determined by the mode diagram.

The turbine is equipped flushing device, allowing flushing of the turbine flow path on the go, with a correspondingly reduced load.

To reduce the warm-up time and improve the conditions for starting the turbine, flanges and studs of the HPC are provided, as well as a supply of live steam to the front seal of the HPC. To ensure the correct operating mode and remote control of the system when starting and stopping the turbine, group drainage is provided through drain expander into the capacitor.

3.3.4 Steam turbine unit PT-80/100-130/13

The heating steam turbine PT-80/100-130/13 with industrial and heating steam extraction is designed to directly drive the TVF-120-2 electric generator with a rotation speed of 50 rps and release heat for production and heating needs.

Power, MW

nominal 80

maximum 100

Steam ratings

pressure, MPa 12.8

temperature, 0 C 555

Consumption of extracted steam for production needs, t/h

nominal 185

maximum 300

upper 0.049-0.245

lower 0.029-0.098

Production selection pressure 1.28

Water temperature, 0 C

nutritious 249

cooling 20

Cooling water consumption, t/h 8000

The turbine has the following adjustable steam extractions:

production with absolute pressure (1.275 ± 0.29) MPa and two heating extractions - upper with absolute pressure in the range of 0.049-0.245 MPa and lower with pressure in the range of 0.029-0.098 MPa. The heating bleed pressure is regulated using one control diaphragm installed in the upper heating bleed chamber. The regulated pressure in the heating outlets is maintained: in the upper outlet - when both heating outlets are turned on, in the lower outlet - when one lower heating outlet is on. Network water must be passed through the network heaters of the lower and upper heating stages sequentially and in equal quantities. The flow of water passing through network heaters must be controlled.

The turbine is a single-shaft two-cylinder unit. The flow part of the HPC has a single-coil control stage and 16 pressure levels.

The flow part of the LPC consists of three parts:

the first (up to the upper heating outlet) has a control stage and 7 pressure levels,

second (between heating extractions) two pressure stages,

the third - a regulating stage and two pressure stages.

High pressure rotor is solid forged. The first ten disks of the low-pressure rotor are forged integrally with the shaft, the remaining three disks are mounted.

The turbine steam distribution is nozzle. At the exit from the HPC, part of the steam goes to the controlled production extraction, the rest is sent to the LPC. Heating extractions are carried out from the corresponding LPC chambers.

To reduce warm-up time and improve start-up conditions, steam heating of flanges and studs and live steam supply to the front seal of the HPC are provided.

The turbine is equipped with a shaft turning device that rotates the shaft line of the turbine unit at a frequency of 3.4 rpm.

The turbine blade apparatus is designed to operate at a network frequency of 50 Hz, which corresponds to a turbine unit rotor speed of 50 rpm (3000 rpm). Allowed long work turbines with a frequency deviation in the network of 49.0-50.5 Hz.

3.3.5 Steam turbine unit R-50/60-130/13-2

The steam turbine with back pressure R-50/60-130/13-2 is designed to drive the TVF-63-2 electric generator with a rotation speed of 50 s -1 and release steam for production needs.

The nominal values ​​of the main parameters of the turbine are given below:

Power, MW

Nominal 52.7

Maximum 60

Initial steam parameters

Pressure, MPa 12.8

Temperature, о С 555

Pressure in the exhaust pipe, MPa 1.3

The turbine has two unregulated steam extractions designed to heat feed water in high-pressure heaters.

Turbine design:

The turbine is a single-cylinder unit with a single crown control stage and 16 pressure stages. All rotor disks are forged integrally with the shaft. Turbine steam distribution with bypass. Fresh steam is supplied to a free-standing steam box containing an automatic shut-off valve, from where the steam is supplied through bypass pipes to four control valves.

The turbine blade apparatus is designed to operate at a frequency of 3000 rpm. Long-term operation of the turbine is allowed when the frequency deviation in the network is 49.0-50.5 Hz

The turbine unit is equipped protective devices for joint shutdown of the PVD with simultaneous activation of the bypass line by sending a signal. Atmospheric diaphragm valves installed on the exhaust pipes and opening when the pressure in the pipes increases to 0.12 MPa.

3.3.6 Steam turbine unit T-110/120-130/13

The heating steam turbine T-110/120-130/13 with heating steam extraction is designed to directly drive the TVF-120-2 electric generator with a rotation speed of 50 r/s and release heat for heating needs.

The nominal values ​​of the main parameters of the turbine are given below.

Power, MW

nominal 110

maximum 120

Steam ratings

pressure, MPa 12.8

temperature, 0 C 555

nominal 732

maximum 770

Limits of change in steam pressure in regulated heating outlet, MPa

upper 0.059-0.245

lower 0.049-0.196

Water temperature, 0 C

nutritious 232

cooling 20

Cooling water consumption, t/h 16000

Steam pressure in the condenser, kPa 5.6

The turbine has two heating outlets - lower and upper, designed for stepwise heating of network water. When heating the network water in stages with steam from two heating outlets, the control maintains the set temperature of the network water behind the upper network heater. When heating the network water with one lower heating outlet, the temperature of the network water is maintained behind the lower network heater.

The pressure in adjustable heating outlets can vary within the following limits:

in the upper 0.059 - 0.245 MPa with two heating extractions turned on,

in the lower 0.049 - 0.196 MPa with the upper heating supply turned off.

The T-110/120-130/13 turbine is a single-shaft unit consisting of three cylinders: HPC, CSD, LPC.

The HPC is single-flow, has a two-coil control stage and 8 pressure levels. The high pressure rotor is solid forged.

The CSD is also single-flow and has 14 pressure levels. The first 8 disks of the medium pressure rotor are forged integrally with the shaft, the remaining 6 are mounted. The guide vane of the first stage of the CSD is installed in the housing, the remaining diaphragms are installed in cages.

The LPC is dual-flow, has two stages in each flow of left and right rotation (one control and one pressure stage). The length of the last stage working blade is 550 mm, the average diameter of the impeller of this stage is 1915 mm. The low pressure rotor has 4 mounted discs.

In order to facilitate the start-up of the turbine from a hot state and increase its maneuverability during operation under load, the temperature of the steam supplied to the penultimate chamber of the front seal of the HPC is increased by mixing hot steam from the control valve rods or from the main steam line. From the last compartments of the seals, the steam-air mixture is sucked off by a seal suction ejector.

To reduce the heating time and improve the turbine start-up conditions, steam heating of the HPC flanges and studs is provided.

The turbine blade apparatus is designed to operate at a network frequency of 50 Hz, which corresponds to a turbine unit rotor speed of 50 rpm (3000 rpm).

Long-term operation of the turbine is allowed with a network frequency deviation of 49.0-50.5 Hz. In emergency situations for the system, short-term operation of the turbine is allowed at a network frequency below 49 Hz, but not below 46.5 Hz (the time is specified in the technical specifications).

Information about the work “Modernization of Almaty CHPP-2 by changing the water-chemical regime of the make-up water preparation system in order to increase the temperature of the network water to 140–145 C”

Specific heat consumption for two-stage heating of network water.

Conditions: G k3-4 = Gin ChSD + 5 t/h; t j - see fig. ; t 1V ≈ 20 °C; W@ 8000 m3/h

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 °C; t 1V ≈ 20 °C; W@ 8000 m3/h; Δ i PEN = 7 kcal/kg

A) on deviation pressure fresh pair from nominal on ± 0.5 MPa (5 kgf/cm2)

α q t = ± 0,05 %; α G 0 = ± 0,25 %

b) on deviation temperature fresh pair from nominal on ± 5 °C

V) on deviation consumption nutritious water from nominal on ± 10 % G 0

G) on deviation temperature nutritious water from nominal on ± 10 °C

A) on shutdown groups PVD

b) on deviation pressure spent pair from nominal

V) on deviation pressure spent pair from nominal

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 °C; G pit = G 0

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 °C

Conditions: G pit = G 0; R 9 = 0.6 MPa (6 kgf/cm2); t pit - see fig. ; t j - see fig.

Conditions: G pit = G 0; t pit - see fig. ; R 9 = 0.6 MPa (6 kgf/cm2)

Conditions: R n = 1.3 MPa (13 kgf/cm2); i n = 715 kcal/kg; t j - see fig.

Note. Z= 0 - the control diaphragm is closed. Z= max - the control diaphragm is fully open.

Conditions: R wto = 0.12 MPa (1.2 kgf/cm2); R 2 = 5 kPa (0.05 kgf/cm2)

Conditions: R n = 1.3 MPa (13 kgf/cm2) at Gin ChSD ≤ 221.5 t/h; R n = Gin ChSD/17 - at Gin ChSD > 221.5 t/h; i n = 715 kcal/kg; R 2 = 5 kPa (0.05 kgf/cm2); t j - see fig. , ; τ2 = f(P WTO) - see fig. ; Q t = 0 Gcal/(kW h)

Conditions: R 0 = 1.3 (130 kgf/cm2); t 0 = 555 °C; R NTO = 0.06 (0.6 kgf/cm2); R 2 @ 4 kPa (0.04 kgf/cm2)

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 ° WITH; P n = 1.3 MPa (13 kgf/cm2); R NTO = 0.09 MPa (0.9 kgf/cm2); R 2 = 5 kPa (0.05 kgf/cm2); G pit = G 0.

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 ° WITH; P n = 1.3 MPa (13 kgf/cm2); R WTO = 0.12 MPa (1.2 kgf/cm2); R 2 = 5 kPa (0.05 kgf/cm2); G pit = G 0; τ2 = 52 ° WITH.

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 ° WITH; P n = 1.3 MPa (13 kgf/cm2); R WTO and R NTO = f(Gin ChSD) - see fig. thirty; R 2 = 5 kPa (0.05 kgf/cm2); G pit = G 0

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 °C; P n = 1.3 MPa (13 kgf/cm2); R NTO = 0.09 MPa (0.9 kgf/cm2); R 2 = 5 kPa (0.05 kgf/cm2); G pit = G 0; Q t = 0

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 °C; P n = 1.3 MPa (13 kgf/cm2); R WTO = 0.12 MPa (1.2 kgf/cm2); R 2 = 5 kPa (0.05 kgf/cm2); G pit = G 0; τ2 = 52 °C; Q t = 0.

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 °C; P n = 1.3 MPa (13 kgf/cm2); R WTO and R NTO = f(Gin ChSD) - see fig. ; R 2 = 5 kPa (0.05 kgf/cm2); G pit = G 0.

A) minimally possible pressure V upper T-selection And calculated temperature reverse network water

b) amendment on temperature reverse network water

1 Based on data from POT LMZ.

On deviation pressure fresh pair from nominal on ±1 MPa (10 kgf/cm2): To complete consumption warmth

To consumption fresh pair

1 Based on data from POT LMZ.

On deviation temperature fresh pair from nominal on ±10°C:

To complete consumption warmth

To consumption fresh pair

1 Based on data from POT LMZ.

On deviation pressure V P-selection from nominal on ± 1 MPa (1 kgf/cm2):

To complete consumption warmth

To consumption fresh pair

A) ferry production selection

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 ° C; P n = 1.3 MPa (13 kgf/cm2); ηem = 0.975.

b) ferry upper And lower district heating selections

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 °C; R WTO = 0.12 MPa (1.2 kgf/cm2); ηem = 0.975

V) ferry lower district heating selection

Conditions: R 0 = 13 MPa (130 kgf/cm2); t 0 = 555 ° C; R NTO = 0.09 MPa (0.9 kgf/cm2); ηem = 0.975

A) on pressure V production selection

b) on pressure V upper heating selection

V) on pressure V lower heating selection

Application

1. CONDITIONS FOR COMPILATION OF ENERGY CHARACTERISTICS

A typical energy characteristic was compiled on the basis of reports on thermal tests of two turbine units: at Chisinau CHPP-2 (work performed by Yuzhtekhenergo) and at CHPP-21 Mosenergo (work performed by MGP PO Soyuztechenergo). The characteristic reflects the average efficiency of a turbine unit that has undergone major renovation and operating according to the thermal circuit shown in Fig. ; under the following parameters and conditions accepted as nominal:

The pressure and temperature of fresh steam in front of the turbine stop valve is 13 (130 kgf/cm2)* and 555 °C;

* In the text and graphs - absolute pressure.

The pressure in the regulated production outlet is 13 (13 kgf/cm2) with a natural increase at flow rates at the entrance to the ChSD of more than 221.5 t/h;

The pressure in the upper district heating extraction is 0.12 (1.2 kgf/cm2) with a two-stage scheme for heating network water;

The pressure in the lower heating outlet is 0.09 (0.9 kgf/cm2) with a single-stage scheme for heating network water;

Pressure in the regulated production extraction, upper and lower heating extractions in condensation mode with pressure regulators turned off - fig. And ;

Exhaust steam pressure:

a) to characterize the condensation mode and work with selections during one-stage and two-stage heating of network water at a constant pressure of 5 kPa (0.05 kgf/cm2);

b) to characterize the condensation regime at constant flow and cooling water temperature - in accordance with the thermal characteristics of the condenser at t 1V= 20 °C and W= 8000 m3/h;

The high and low pressure regeneration system is fully turned on, the deaerator 0.6 (6 kgf/cm2) is powered by production steam;

Feed water consumption is equal to fresh steam consumption, 100% of production condensate is returned at t= 100 °C carried out in a deaerator 0.6 (6 kgf/cm2);

The temperature of the feed water and the main condensate behind the heaters corresponds to the dependencies shown in Fig. , , , , ;

The increase in enthalpy of feed water in the feed pump is 7 kcal/kg;

The electromechanical efficiency of the turbine unit was adopted based on testing of a similar turbine unit carried out by Dontekhenergo;

Limits of pressure regulation in selections:

a) production - 1.3 ± 0.3 (13 ± 3 kgf/cm2);

b) upper district heating with a two-stage heating scheme for heating water - 0.05 - 0.25 (0.5 - 2.5 kgf/cm2);

a) lower district heating with a single-stage heating scheme for heating water - 0.03 - 0.10 (0.3 - 1.0 kgf/cm2).

Heating of network water in a district heating plant with a two-stage scheme for heating network water, determined by factory calculated dependencies τ2р = f(P VTO) and τ1 = f(Q T, P WTO) is 44 - 48 °C for maximum heating loads at pressures P WTO = 0.07 ÷ 0.20 (0.7 ÷ 2.0 kgf/cm2).

The test data forming the basis of this Standard Energy Characteristic was processed using the “Tables of Thermophysical Properties of Water and Water Steam” (M.: Standards Publishing House, 1969). According to the conditions of the LMZ POT, the return condensate of the production selection is introduced at a temperature of 100 ° C into the main condensate line after HDPE No. 2. When compiling the Typical Energy Characteristics, it is accepted that it is introduced at the same temperature directly into the deaerator 0.6 (6 kgf/cm2) . According to the conditions of the LMZ POT, with two-stage heating of network water and modes with a steam flow rate at the entrance to the CSD of more than 240 t/h (maximum electrical load with low production output), HDPE No. 4 is completely switched off. When compiling the Standard Energy Characteristics, it was accepted that when the flow rate at the entrance to the CSD is over 190 t/h, part of the condensate is directed to the HDPE bypass No. 4 in such a way that its temperature in front of the deaerator does not exceed 150 °C. This is required to ensure good deaeration of the condensate.

2. CHARACTERISTICS OF THE EQUIPMENT INCLUDED IN THE TURBO PLANT

Along with the turbine, the turbine unit includes the following equipment:

Generator TVF-120-2 from the Elektrosila plant with hydrogen cooling;

Two-pass capacitor 80 KTSS-1 with a total surface of 3000 m2, of which 765 m2 is the share of the built-in beam;

Four low-pressure heaters: HDPE No. 1, built into the condenser, HDPE No. 2 - PN-130-16-9-11, HDPE No. 3 and 4 - PN-200-16-7-1;

One deaerator 0.6 (6 kgf/cm2);

Three high-pressure heaters: PVD No. 5 - PV-425-230-23-1, PVD No. 6 - PV-425-230-35-1, PVD No. 7 - PV-500-230-50;

Two circulation pumps 24NDN with a flow of 5000 m3/h and a pressure of 26 m of water. Art. with electric motors of 500 kW each;

Three condensate pumps KN 80/155 driven by electric motors with a power of 75 kW each (the number of pumps in operation depends on the steam flow to the condenser);

Two main three-stage ejectors EP-3-701 and one starting ejector EP1-1100-1 (one main ejector is constantly in operation);

Two network water heaters (upper and lower) PSG-1300-3-8-10 with a surface area of ​​1300 m2 each, designed to pass 2300 m3/h of network water;

Four condensate pumps of KN-KS 80/155 network water heaters driven by electric motors with a power of 75 kW each (two pumps for each PSG);

One network pump of the first lift SE-5000-70-6 with a 500 kW electric motor;

One network pump II lift SE-5000-160 with a 1600 kW electric motor.

3. CONDENSATION MODE

In condensation mode with pressure regulators turned off, the total gross heat consumption and fresh steam consumption, depending on the power at the generator terminals, are expressed by the equations:

At constant condenser pressure

P 2 = 5 kPa (0.05 kgf/cm2);

Q 0 = 15,6 + 2,04N T;

G 0 = 6,6 + 3,72N t + 0.11( N t - 69.2);

At constant flow ( W= 8000 m3/h) and temperature ( t 1V= 20 °C) cooling water

Q 0 = 13,2 + 2,10N T;

G 0 = 3,6 + 3,80N t + 0.15( N t - 68.4).

The above equations are valid within the power range from 40 to 80 MW.

The consumption of heat and fresh steam during condensation mode for a given power is determined from the given dependencies with the subsequent introduction of the necessary corrections according to the corresponding graphs. These amendments take into account the difference between operating conditions and nominal ones (for which the Typical Characteristics were compiled) and serve to recalculate the characteristics data to operating conditions. During reverse recalculation, the signs of the amendments are reversed.

The amendments adjust the consumption of heat and fresh steam at a constant power. When several parameters deviate from the nominal values, the corrections are algebraically summed up.

4. MODE WITH ADJUSTABLE SELECTIONS

When the controlled extractions are turned on, the turbine unit can operate with single-stage and two-stage heating schemes for heating water. It is also possible to work without heating extraction with one production unit. The corresponding typical diagrams of modes for steam consumption and the dependence of specific heat consumption on power and production output are given in Fig. - , and specific electricity generation from heat consumption in Fig. - .

The mode diagrams are calculated according to the scheme used by POT LMZ and are shown in two fields. The upper field is a diagram of the modes (Gcal/h) of a turbine with one production extraction at Q t = 0.

When the heating load is turned on and other unchanged conditions, either only stages 28 - 30 are unloaded (with one lower mains heater turned on), or stages 26 - 30 (with two mains heaters turned on) and the turbine power is reduced.

The power reduction value depends on the heating load and is determined

Δ N Qt = KQ T,

Where K- specific change in turbine power Δ determined during testing N Qt/Δ Q t equal to 0.160 MW/(Gcal h) with single-stage heating, and 0.183 MW/(Gcal h) with two-stage heating of network water (Fig. 31 and 32).

It follows that the fresh steam consumption at a given power N t and two (production and heating) extractions will correspond to some fictitious power in the upper field N ft and one production selection

N ft = N t + Δ N Qt.

The inclined straight lines in the lower field of the diagram allow you to determine graphically the value of the given turbine power and heating load N ft, and according to it and production selection, fresh steam consumption.

The values ​​of specific heat consumption and specific electricity generation for thermal consumption are calculated based on data taken from the calculation of regime diagrams.

The graphs of the dependence of specific heat consumption on power and production output are based on the same considerations as the basis for the LMZ POT mode diagram.

A schedule of this type was proposed by the turbine shop of the MGP PO Soyuztekhenergo (Industrial Energy, 1978, No. 2). It is preferable to a charting system q t = f(N T, Q t) at different Q n = const, since it is more convenient to use. For unprincipled reasons, the graphs of specific heat consumption are made without a lower field; the methodology for using them is explained with examples.

The typical characteristic does not contain data characterizing the mode for three-stage heating of network water, since such a mode in installations of this type during the testing period it was not mastered anywhere.

The influence of deviations of parameters from those accepted when calculating the Typical Characteristics as nominal is taken into account in two ways:

a) parameters that do not affect heat consumption in the boiler and heat supply to the consumer at constant mass flow rates G 0, G n and G t, - by introducing amendments to the specified power N T( N t + KQ T).

According to this corrected power according to Fig. - fresh steam consumption is determined, specific consumption heat and total heat consumption;

b) corrections for P 0, t 0 and P n are added to those found after making the above amendments to the fresh steam flow rate and the total heat flow rate, after which the fresh steam flow rate and heat flow rate (total and specific) are calculated for the given conditions.

Data for live steam pressure correction curves are calculated using test results; all other correction curves are based on LMZ POT data.

5. EXAMPLES OF DETERMINING SPECIFIC HEAT CONSUMPTION, FRESH STEAM CONSUMPTION AND SPECIFIC HEATING WORKS

Example 1. Condensation mode with disconnected pressure regulators in the selections.

Given: N t = 70 MW; P 0 = 12.5 (125 kgf/cm2); t 0 = 550 °C; R 2 = 8 kPa (0.08 kgf/cm2); G pit = 0.93 G 0; Δ t pit = t pete - t npit = -7 °C.

It is required to determine the total and specific gross heat consumption and fresh steam consumption under given conditions.

The sequence and results are given in table. .

Table P1

* Pressures in the ChSND selections and condensate temperature in the HDPE can be determined from condensation regime graphs depending on G ChSDin, with the ratio G CHSDin/ G 0 = 0,83.

6. LEGEND

TECHNICAL DESCRIPTION

Description of the object.
Full name:“Automated training course “Operation of the PT-80/100-130/13 turbine.”
Symbol:
Year of issue: 2007.

The automated training course for the operation of the turbine PT-80/100-130/13 was developed for the training of operational personnel servicing turbine units of this type and is a means of training, pre-examination preparation and examination testing of thermal power plant personnel.
The AUK was compiled on the basis of regulatory and technical documentation used in the operation of PT-80/100-130/13 turbines. It contains text and graphic material for interactive learning and testing of students.
This AUC describes the design and technological characteristics main and auxiliary equipment heating turbines PT-80/100-130/13, namely: main steam valves, stop valve, control valves, HPC steam inlet, design features of HPC, CSD, LPC, turbine rotors, bearings, shaft turning device, sealing system, condensing unit, low pressure regeneration, feed pumps, high pressure regeneration, district heating plant, turbine oil system, etc.
The starting, normal, emergency and stopping modes of operation of a turbine unit are considered, as well as the main reliability criteria for heating and cooling steam pipelines, valve blocks and turbine cylinders.
System considered automatic regulation turbines, protection, interlocking and alarm systems.
The procedure for admission to inspection, testing, and repair of equipment, safety rules and fire and explosion safety have been determined.

AUC composition:

Automated training course (ATC) is a software tool designed for initial training and subsequent testing of knowledge of personnel of power plants and electrical networks. First of all, for training operational and maintenance personnel.
The basis of the AUC is the current production and job descriptions, regulatory materials, and data from equipment manufacturers.
AUC includes:
— section of general theoretical information;
— a section that discusses the design and operating rules of a specific type of equipment;
— student self-test section;
- examiner's block.
In addition to texts, the AUK contains the necessary graphic material (diagrams, drawings, photographs).

Information content of the AUC.

1. The text material is compiled on the basis of operating instructions, turbine PT-80/100-130/13, factory instructions, other regulatory and technical materials and includes the following sections:

1.1. Operation of the turbine unit PT-80/100-130/13.
1.1.1. General information about the turbine.
1.1.2. Oil system.
1.1.3. Regulation and protection system.
1.1.4. Condensation device.
1.1.5. Regenerative installation.
1.1.6. Installation for heating network water.
1.1.7. Preparing the turbine for operation.
Preparation and commissioning of the oil system and VPU.
Preparation and activation of the turbine control and protection system.
Testing of protections.
1.1.8. Preparing and putting into operation the condensing device.
1.1.9. Preparation and commissioning of the regenerative installation.
1.1.10. Preparing the installation for heating network water.
1.1.11. Preparing the turbine for start-up.
1.1.12. General instructions, which must be performed when starting the turbine from any state.
1.1.13. Starting the turbine from a cold state.
1.1.14. Starting the turbine from a hot state.
1.1.15. Operating mode and changing parameters.
1.1.16. Condensation mode.
1.1.17. Mode with selections for production and heating.
1.1.18. Load dumping and loading.
1.1.19. Stopping the turbine and returning the system to its original state.
1.1.20. Checking technical condition and maintenance. Timing for security checks.
1.1.21. Maintenance lubrication systems and VPU.
1.1.22. Maintenance of condensing and regenerative plant.
1.1.23. Maintenance of installation for heating network water.
1.1.24. Safety precautions when servicing a turbogenerator.
1.1.25. Fire safety when servicing turbine units.
1.1.26. Procedure for testing safety valves.
1.1.27. Application (protection).

2. The graphic material in this AUC is presented in 15 drawings and diagrams:
2.1. Lengthwise cut turbines PT-80/100-130-13 (HPC).
2.2. Longitudinal section of the turbine PT-80/100-130-13 (TSSND).
2.3. Scheme of steam extraction pipelines.
2.4. Diagram of oil pipelines of a turbogenerator.
2.5. Scheme of supply and suction of steam from seals.
2.6. Stuffing box heater PS-50.
2.7. Characteristics of the stuffing box heater PS-50.
2.8. Diagram of the main condensate of a turbogenerator.
2.9. Diagram of network water pipelines.
2.10. Pipeline diagram for suction of steam-air mixture.
2.11. PVD protection scheme.
2.12. Diagram of the main steam pipeline of the turbine unit.
2.13. Turbine unit drainage diagram.
2.14. Diagram of the gas-oil system of the TVF-120-2 generator.
2.15. Energy characteristics of the PT-80/100-130/13 LMZ tubing unit.

Check of knowledge

After studying the text and graphic material, the student can run a self-test program. The program is a test that checks the degree of assimilation of the instruction material. In case of an incorrect answer, the operator receives an error message and a quote from the instruction text containing the correct answer. The total number of questions for this course is 300.

Exam

After completing the training course and self-testing of knowledge, the student takes an examination test. It includes 10 questions automatically selected at random from among the questions provided for self-test. During the examination, the examinee is asked to answer these questions without prompting or the opportunity to refer to a textbook. No error messages are displayed until testing is completed. After finishing the exam, the student receives a protocol that sets out the proposed questions, the answer options chosen by the examinee, and comments on erroneous answers. The exam is graded automatically. The testing protocol is saved on the computer's hard drive. It is possible to print it on a printer.

• Tutorial

Preface to the first part

Modeling steam turbines is a daily task for hundreds of people in our country. Instead of a word model it's common to say flow characteristic. The flow characteristics of steam turbines are used to solve such problems as calculating the specific consumption of equivalent fuel for electricity and heat produced by thermal power plants; optimization of CHP operation; planning and maintaining CHP modes.

Developed by me new flow characteristics of a steam turbine— linearized flow characteristic of a steam turbine. The developed flow characteristic is convenient and effective in solving these problems. However, at the moment it is described only in two scientific works:

1. Optimization of the operation of thermal power plants in the conditions of the wholesale electricity and capacity market in Russia;
2. Computational methods for determining the specific consumption of equivalent fuel from thermal power plants for supplied electrical and thermal energy in the combined generation mode.

And now in my blog I would like to:

• firstly, simple and accessible language answer basic questions about the new flow characteristic (see Linearized flow characteristic of a steam turbine. Part 1. Basic questions);
• secondly, provide an example of constructing a new flow characteristic, which will help to understand both the construction method and the properties of the characteristic (see below);
• thirdly, to refute two well-known statements regarding the operating modes of a steam turbine (see Linearized flow characteristic of a steam turbine. Part 3. Debunking myths about the operation of a steam turbine).

1. Initial data

The initial data for constructing a linearized flow characteristic can be

1. actual power values ​​Q 0 , N, Q p, Q t measured during the operation of the steam turbine,
2. nomograms q t gross from regulatory and technical documentation.

In cases where the actual values ​​of Q 0 , N, Q p, Q t are not available, nomograms q t gross can be processed. These, in turn, were obtained based on measurements. Read more about turbine testing in V.M. Gornshtein. and etc. Methods for optimizing power system modes.

2. Algorithm for constructing a linearized flow characteristic

The construction algorithm consists of three steps.

1. Translation of nomograms or measurement results into tabular form.
2. Linearization of the flow characteristic of a steam turbine.
3. Determination of the boundaries of the control range of steam turbine operation.

When working with nomograms q t gross, the first step is carried out quickly. This kind of work is called digitization(digitizing). Digitizing 9 nomograms for the current example took me about 40 minutes.

The second and third steps require the use of mathematical packages. I love and have been using MATLAB for many years. My example of constructing a linearized flow characteristic is made exactly in it. The example can be downloaded from the link, run and independently understand the method of constructing a linearized flow characteristic.

The flow characteristic for the turbine under consideration was plotted for the following fixed values ​​of the mode parameters:

• single-stage operating mode,
• medium pressure steam pressure = 13 kgf/cm2,
• low pressure steam pressure = 1 kgf/cm2.

1) Nomograms of specific consumption q t gross for electricity generation (the marked red dots are digitized and transferred to the table):

• PT80_qt_Qm_eq_0_digit.png,
• PT80_qt_Qm_eq_100_digit.png,
• PT80_qt_Qm_eq_120_digit.png,
• PT80_qt_Qm_eq_140_digit.png,
• PT80_qt_Qm_eq_150_digit.png,
• PT80_qt_Qm_eq_20_digit.png,
• PT80_qt_Qm_eq_40_digit.png,
• PT80_qt_Qm_eq_60_digit.png,
• PT80_qt_Qm_eq_80_digit.png.

2) Digitization result(to each csv file corresponds to a png file):

• PT-80_Qm_eq_0.csv,
• PT-80_Qm_eq_100.csv,
• PT-80_Qm_eq_120.csv,
• PT-80_Qm_eq_140.csv,
• PT-80_Qm_eq_150.csv,
• PT-80_Qm_eq_20.csv,
• PT-80_Qm_eq_40.csv,
• PT-80_Qm_eq_60.csv,
• PT-80_Qm_eq_80.csv.

3) MATLAB script with calculations and graphing:

• PT_80_linear_characteristic_curve.m

4) The result of digitizing nomograms and the result of constructing a linearized flow characteristic in tabular form:

• PT_80_linear_characteristic_curve.xlsx.

Step 1. Translation of nomograms or measurement results into tabular form

1. Processing of initial data

The initial data for our example are nomograms q t gross.

To convert many nomograms into digital form you need special tool. I have used the web application many times for these purposes. The application is simple and convenient, but does not have enough flexibility to automate the process. Some of the work has to be done manually.

At this step, it is important to digitize the extreme points of the nomograms, which set the boundaries of the control range of the steam turbine.

The work consisted of marking the points of the flow characteristic in each png file using the application, downloading the resulting csv and collecting all the data in one table. The result of digitization can be found in the file PT-80-linear-characteristic-curve.xlsx, sheet “PT-80”, table “Initial data”.

2. Conversion of units of measurement to units of power

$$display$$\begin(equation) Q_0 = \frac (q_T \cdot N) (1000) + Q_P + Q_T \qquad (1) \end(equation)$$display$$

The resulting table “Initial data (units of power)” is the result of the first step of the algorithm.

Step 2. Linearization of the steam turbine flow characteristic

1. Checking the operation of MATLAB

At this step you need to install and open MATLAB version no lower than 7.3 (this old version, current 8.0). In MATLAB, open the file PT_80_linear_characteristic_curve.m, run it and make sure it works. Everything works correctly if, after running the script on the command line, you see the following message:

If you have any errors, figure out how to fix them yourself.

2. Computations

All calculations are implemented in the file PT_80_linear_characteristic_curve.m. Let's look at it in parts.

1) Specify the name of the source file, sheet, range of cells containing the “Initial data (units of power)” table obtained in the previous step.

2) We calculate the initial data in MATLAB.

We use the variable Qm for the average pressure steam flow Q p, index m from middle- average; similarly we use the variable Ql for low pressure steam flow Qn, index l from low- short.

3) Let's determine the coefficients α i .

Let us recall the general formula for the flow characteristics

$$display$$\begin(equation) Q_0 = f(N, Q_P, Q_T) \qquad (2) \end(equation)$$display$$

and indicate the independent (x_digit) and dependent (y_digit) variables.

If you don’t understand why there is a unit vector (last column) in the x_digit matrix, then read the materials on linear regression. On the topic of regression analysis, I recommend the book Draper N., Smith H. Applied regression analysis. New York: Wiley, In press, 1981. 693 p. (available in Russian).

Equation of the linearized flow characteristic of a steam turbine

$$display$$\begin(equation) Q_0 = \alpha_N \cdot N + \alpha_P \cdot Q_P + \alpha_T \cdot Q_T + \alpha_0 \qquad (3) \end(equation)$$display$$

is a multiple linear regression model. We will determine the coefficients α i using "great benefit of civilization"- method least squares. Separately, I note that the least squares method was developed by Gauss in 1795.

In MATLAB this is done in one line.

Variable A contains the required coefficients (see message on the MATLAB command line).

Thus, the resulting linearized flow characteristic of the PT-80 steam turbine has the form

$$display$$\begin(equation) Q_0 = 2.317 \cdot N + 0.621 \cdot Q_P + 0.255 \cdot Q_T + 33.874 \qquad (4) \end(equation)$$display$$

4) Let us estimate the linearization error of the resulting flow characteristic.

Linearization error is 0.57%(see message on MATLAB command line).

To assess the ease of use of the linearized flow characteristic of a steam turbine, let us solve the problem of calculating the flow rate of high-pressure steam Q 0 at known values loads N, Q p, Q t.

Let N = 82.3 MW, Q p = 55.5 MW, Q t = 62.4 MW, then

$$display$$\begin(equation) Q_0 = 2.317 \cdot 82.3 + 0.621 \cdot 55.5 + 0.255 \cdot 62.4 + 33.874 = 274.9 \qquad (5) \end(equation)$$ display$$

Let me remind you that the average calculation error is 0.57%.

Let's return to the question: why is the linearized flow characteristic of a steam turbine fundamentally more convenient than nomograms of specific consumption q t gross for electricity generation? To understand the fundamental difference in practice, solve two problems.

1. Calculate the Q 0 value to the specified accuracy using nomograms and your eyes.
2. Automate the process of calculating Q 0 using nomograms.

Obviously, in the first problem, determining the values ​​of q t gross by eye is fraught with gross errors.

The second task is cumbersome to automate. Because the the values ​​of q t gross are nonlinear, then for such automation the number of digitized points is tens of times greater than in the current example. Digitization alone is not enough, it is also necessary to implement the algorithm interpolation(finding values ​​between points) non-linear gross values.

Step 3. Determining the boundaries of the control range of the steam turbine

1. Calculations

To calculate the adjustment range we will use another "a blessing of civilization"— convex hull method, convex hull.

In MATLAB this is done as follows.

The convhull() method defines limit points of the adjustment range, specified by the values ​​of the variables N, Qm, Ql. The indexCH variable contains the vertices of triangles constructed using Delaunay triangulation. The regRange variable contains the boundary points of the adjustment range; variable regRangeQ0 - high pressure steam flow rates for the boundary points of the control range.

The result of the calculations can be found in the file PT_80_linear_characteristic_curve.xlsx, sheet “PT-80-result”, table “Limits of the adjustment range”.

The linearized flow characteristic has been constructed. It represents a formula and 37 points that define the boundaries (envelope) of the adjustment range in the corresponding table.

2. Check

When automating the processes of calculating Q 0, it is necessary to check whether a certain point with the values ​​N, Q p, Q t is inside the adjustment range or outside it (the mode is not technically feasible). In MATLAB this can be done as follows.

We set the values ​​N, Q p, Q t that we want to check.

Let's check.

The check is carried out in two steps:

• the variable in1 shows whether the values ​​of N, Q p fell inside the projection of the shell on the N, Q p axes;
• similarly, the variable in2 shows whether the values ​​of Q p, Q t fell inside the projection of the shell on the Q p, Q t axes.

If both variables are equal to 1 (true), then the desired point is inside the shell, which specifies the control range of the steam turbine.

Illustration of the resulting linearized steam turbine flow characteristic

Most "generous benefits of civilization" we got to illustrate the calculation results.

First of all, we must say that the space in which we build graphs, i.e., the space with axes x - N, y - Q t, z - Q 0, w - Q p, is called regime space(see Optimization of the operation of thermal power plants in the conditions of the wholesale electricity and capacity market in Russia

). Each point in this space determines a certain operating mode of the steam turbine. The mode may be

• technically feasible if the point is inside the shell that defines the adjustment range,
• technically not feasible if the point is outside this shell.

If we talk about the condensation mode of operation of a steam turbine (Q p = 0, Q t = 0), then linearized flow characteristic represents straight segment. If we talk about a T-type turbine, then the linearized flow characteristic is flat polygon in three-dimensional mode space with axes x – N, y – Q t, z – Q 0, which is easy to visualize. For a PT-type turbine, visualization is the most complex, since the linearized flow characteristic of such a turbine represents flat polygon in four-dimensional space(for explanations and examples, see Optimizing the operation of thermal power plants in the conditions of the Russian wholesale electricity and capacity market, section Linearization of turbine flow characteristics).

1. Illustration of the resulting linearized flow characteristic of a steam turbine

Let's construct the values ​​of the table “Initial data (units of power)” in regime space.

Rice. 3. Starting points flow characteristics in regime space with axes x – N, y – Q t, z – Q 0

Since we cannot construct a dependence in four-dimensional space, we have not yet reached such a benefit of civilization, we operate with the values ​​of Q n as follows: we exclude them (Fig. 3), fix them (Fig. 4) (see the code for constructing graphs in MATLAB).

Let us fix the value of Q p = 40 MW and construct the starting points and the linearized flow characteristic.

Rice. 4. Initial points of the flow characteristic (blue points), linearized flow characteristic (green flat polygon)

Let's return to the formula we obtained for the linearized flow characteristic (4). If we fix Q p = 40 MW MW, then the formula will look like

$$display$$\begin(equation) Q_0 = 2.317 \cdot N + 0.255 \cdot Q_T + 58.714 \qquad (6) \end(equation)$$display$$

This model defines a flat polygon in three-dimensional space with axes x – N, y – Q t, z – Q 0 by analogy with a T-type turbine (we see it in Fig. 4).

Many years ago, when nomograms for q t gross were being developed, a fundamental mistake was made at the stage of analyzing the initial data. Instead of using the least squares method and constructing a linearized flow characteristic of a steam turbine, for some unknown reason, a primitive calculation was made:

$$display$$\begin(equation) Q_0(N) = Q_e = Q_0 - Q_T - Q_P \qquad (7) \end(equation)$$display$$

We subtracted the vapor consumption Q t, Q p from the high-pressure steam consumption Q 0 and attributed the resulting difference Q 0 (N) = Q e to electricity generation. The resulting value Q 0 (N) = Q e was divided by N and converted to kcal/kWh, obtaining the specific consumption q t gross. This calculation does not comply with the laws of thermodynamics.

Dear readers, maybe you know the unknown reason? Share it!

2. Illustration of the adjustment range of a steam turbine

Let's look at the shell of the adjustment range in the regime space. The starting points for its construction are presented in Fig. 5. These are the same points that we see in Fig. 3, however, the parameter Q 0 is now excluded.

Rice. 5. Initial points of the flow characteristic in the regime space with axes x – N, y – Q p, z – Q t

Many points in Fig. 5 is convex. Using the convexhull() function, we have identified the points that define the outer shell of this set.

Delaunay triangulation(a set of connected triangles) allows us to construct the control range envelope. The vertices of the triangles are the boundary values ​​of the control range of the PT-80 steam turbine we are considering.

Rice. 6. Shell of the adjustment range, represented by many triangles

When we checked a certain point for falling inside the adjustment range, we checked whether this point lay inside or outside the resulting shell.

All graphs presented above were constructed using MATLAB (see PT_80_linear_characteristic_curve.m).

Promising problems associated with the analysis of steam turbine operation using linearized flow characteristics

If you are doing a diploma or dissertation, I can offer you several tasks, the scientific novelty of which you can easily prove to the whole world. In addition, you will do excellent and useful work.

Problem 1

Show how a flat polygon changes when the low-pressure vapor pressure Qt changes.

Problem 2

Show how a flat polygon changes when the pressure in the condenser changes.

Problem 3

Check whether the coefficients of the linearized flow characteristic can be represented as functions of additional mode parameters, namely:

$$display$$\begin(equation) \alpha_N = f(p_(0),...); \\ \alpha_P = f(p_(P),...); \\ \alpha_T = f(p_(T),...); \\ \alpha_0 = f(p_(2),...). \end(equation)$$display$$

Here p 0 is the high pressure steam pressure, p p is the medium pressure steam pressure, p t is the low pressure steam pressure, p 2 is the exhaust steam pressure in the condenser, all units are kgf/cm2.

Justify the result.

Links

Chuchueva I.A., Inkina N.E. Optimization of the operation of thermal power plants in the conditions of the wholesale electricity and power market in Russia // Science and education: scientific publication of MSTU im. N.E. Bauman. 2015. No. 8. P. 195-238.

• Section 1. Meaningful formulation of the problem of optimizing the operation of thermal power plants in Russia
• Section 2. Linearization of turbine flow characteristics