JP2000265804A - Method and device for controlling operation of steam turbine generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively use the steam by basically achieving the speed governing control, or automatically setting the power generation to achieve the governing control so that the power generation becomes a set value when the power reception is lower than the set value, and returning to the governing control when the power reception is not less than the set value, and the main steam pressure is not more than the set value. SOLUTION: During the regular operation, the governing control mode is implemented to generate the power according to the main steam pressure on a pressure controller 7 side by a mode change-over switch 12, and if the power reception is lower than the set value, the mode change-over switch 12 is changed to the power controller 11 side, the power reception is set to the set value, and the mode is changed to the governing control mode. If the power reception exceeds the set value, and the main steam pressure is not more than the set value under the governing control, the mode is returned to the governing control mode. During the operation in the governing control mode, if the power generation exceeds the rated power of a generator, the power is set to the rated value, and the mode is changed to the governing control mode. If the power generation becomes not more than the rated power of the generator under the governing control, and the main steam pressure becomes not more than the set value, the mode is returned to the governing control mode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for controlling the operation of a steam turbine generator used for effectively utilizing steam generated in a boiler plant.

[0002]

2. Description of the Related Art In a boiler plant having a steam turbine generator connected to a system and capable of preventing reverse power flow, a turbine control mode is usually set as a generator control mode by controlling a turbine governor so as to achieve a set power generation amount. The constant power generation mode is used to perform control, but in addition to this constant power generation mode, the turbine speed control is performed by automatically setting the power generation amount to the set received power amount, and the power generation amount is rated. The power receiving constant control mode for increasing the amount of received power when the power is exceeded, and the pressure regulation control mode for generating power in accordance with the main steam pressure are used as required.

[0003]

However, in the above-described constant power generation control mode, the generated steam amount fluctuates.
In order to stably generate power, the setting must be adjusted to a smaller amount of steam than the average amount of steam generated, so that a certain amount or more of unnecessary steam is always generated,
Further, for example, when the power used on the premises is 2500 KW and the generated power is 2000 KW, the power used on the premises is 2500 KW.
When the power is reduced from 1500 KW to 1500 KW, the generated power is constant, resulting in a surplus of 500 KW, causing a reverse power flow and possibly causing a power receiving trip.

On the other hand, in the above-described constant power receiving control mode, if there is no steam generation amount corresponding to the automatically set power generation amount,
There is a risk that the main steam pressure of the turbine will decrease. If there is more steam than the amount of steam generated corresponding to the automatically set power generation amount, the steam will be wasted.

Further, in the above-described pressure regulation control mode, if the generated power exceeds the rated power of the generator, an overcurrent trip occurs, and if the received power decreases due to an increase in the generated power, There is a possibility that a reverse power flow will occur and a power receiving trip will occur.

[0006] Therefore, the present invention uses the steam generated in the boiler for power generation as much as possible to achieve effective use of the steam and to cope with any fluctuations in the amount of steam generated, the amount of steam used, and the electric power used in the premises. An object of the present invention is to provide a method and an apparatus for controlling the operation of a steam turbine generator that can automatically respond to the operation.

[0007]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a steam turbine for supplying steam generated in a boiler and stored in a high-pressure steam reservoir to a steam turbine through a steam line. By controlling the turbine inlet pressure by operating the turbine governor at the inlet, pressure control is performed so that power is generated in accordance with the main steam pressure. Speed control is performed by automatically setting the amount of power generation so that the power generation becomes equal to or higher than the set value and returning to the pressure control when the main steam pressure falls below the set value. When the power exceeds the rated power of the generator, the power generation is set to the rated power of the generator and the speed control is performed. When the generated power is less than the rated power of the generator and the main steam pressure falls below the set value, the pressure regulation control is performed. Return to And operation control method and apparatus Unisuru steam turbine generator.

[0008] Since the pressure regulation control is basically employed, the turbine main steam pressure can be stabilized, and all steam can be used for power generation. Further, it becomes possible to automatically cope with fluctuations in the amount of generated steam, fluctuations in the amount of used steam, fluctuations in the power used in the premises, and the like.

Further, at the time of speed control, the amount of surplus steam released to the high-pressure steam condenser is controlled by operating the high-pressure steam condenser inlet valve in the relief line connected in the middle of the steam line. , It is possible to directly control the pressure of the high-pressure steam reservoir.

[0010]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows an operation control device for a steam turbine generator according to the present invention. A high-pressure steam reservoir 1 for storing steam generated by a boiler (not shown) and a steam turbine 3 of a steam turbine generator 2 are shown. Are connected by a steam line 4, a turbine governor 5 is provided at a turbine inlet of the steam line 4, and a pressure-type thermometer 6 is attached to the steam line 4 upstream of the turbine governor 5.
A pressure controller 7 for sending an operation command signal b to the turbine governor 5 to control the pressure of the steam turbine 3 based on the signal a detected by the pressure thermometer 6 is provided. The signal c detected by the power generation wattmeter 8 and the signal d detected by the power reception wattmeter 9 are sent to the main controller 10, and the detection signal c of the power generation wattmeter 8 and the signal from the main controller 10 are transmitted. A power controller 11 for sending an operation command signal f to the turbine governor 5 based on the setting signal e to control the speed of the steam turbine 3 is provided, and a mode switching command signal g from the main controller 10 is provided. A mode changeover switch 12 for switching between an operation command signal b for pressure regulation control and an operation command signal f for speed regulation control to the turbine governor 5 is provided, and a relief line 13 is connected in the middle of the steam line 4 by branch connection. Along with The relief line 13 is connected to a high-pressure steam condenser 14, an inlet valve 15 is provided at an inlet of the high-pressure steam condenser 14, and a detection signal h of a pressure-type thermometer 16 installed in the high-pressure steam reservoir 1 is provided. An operation command signal j is sent to the inlet valve 15 on the basis of the setting signal i from the main controller 10 based on the detection signal a and the detection signal a so that the steam in the high-pressure steam reservoir 1 is released to the high-pressure steam condenser 14. Provided with a pressure controller 17 for the purpose.

In the operation control device for a steam turbine generator having the above configuration, the main controller 10 has the following functions. That is, when the steam stored in the high-pressure steam reservoir 1 is supplied to the steam turbine 3 through the steam line 4, an operation command is issued from the pressure controller 7 to the turbine governor 5 based on the detection signal a of the pressure thermometer 6. A function based on a pressure regulation control mode in which the signal b is sent to control the turbine inlet pressure to generate power in accordance with the main steam pressure, and when the received power falls below the set received power, A function of automatically setting the power generation amount so as to perform the speed regulation control mode, and returning to the pressure regulation control mode when the received power is equal to or more than the set value and the main steam pressure is equal to or less than the set value, When the power generation exceeds the generator rated power, the power generation is set to the generator rated power and the speed control mode is executed, and the generated power is below the generator rated power and the main steam pressure is below the set value. At the time And ability to return to the control mode, when the generated power increase received power is reduced also, a function to switch to automatic in governor control mode,
The configuration provided in the main controller 10 is adopted.

In the speed control mode, the inlet valve 15 of the high-pressure steam condenser 14 is operated to allow the excess pressure to escape from the high-pressure steam reservoir 1 to the high-pressure steam condenser 14 via the steam line 4 and the relief line 13. By changing the amount of steam, the pressure of the high-pressure steam reservoir 1 is directly controlled.

During normal operation, the mode changeover switch 12 is located at the pressure controller 7 side to execute a pressure regulation control mode for generating power according to the main steam pressure. The turbine governor 5 is operated by the operation command signal b from the pressure controller 7 based on the signal a, and the inlet pressure of the steam turbine 3 is controlled by changing the generated power. At this time, pressure control of the high-pressure steam reservoir 1 by releasing excess steam to the high-pressure steam condenser 14 is not performed, and only the minimum steam necessary for the warm pipe is allowed to flow. However, in order to prevent the pressure of the high-pressure steam reservoir 1 from increasing due to a turbine trip or the like, the pressure control of the high-pressure steam reservoir 1 is continued at a pressure higher than the turbine main steam pressure setting, and the control of the turbine governor 5 is simultaneously performed. Try to avoid interference. Note that the set pressure is automatically changed.

In the above-mentioned operating state, when the received power falls below the set received power amount, the main controller 10 automatically sets the generated power amount to the set received power amount based on the detection signal d of the received power meter 9, and controls the speed. Switch to control mode. in this case,
The mode switching switch 12 is switched to the power controller 11 by the mode switching command signal g output from the main controller 10, and the power generation amount setting signal e is sent to the power controller 11. In 11, the operation command signal f is output to the turbine governor 5 so that the value of the detection signal c of the power generator 8 becomes the value of the setting signal e. This prevents reverse power flow. When the received power exceeds the set power and the main steam pressure becomes equal to or less than the set value due to the speed control, at that time, the mode changeover switch 12 is switched to the pressure controller 7 again to return to the pressure control mode.

On the other hand, when the main controller 10 detects that the power generation exceeds the rated power of the generator based on the detection signal c of the power generator 8 during the operation in the pressure regulation control mode, the power generation Is set to the rated power, and the mode is switched to the speed control mode. Also in this case, similarly to the above case, the mode changeover switch 12 is switched to the power controller 11 side, and the operation command signal f is transmitted from the power controller 11 to the turbine governor 5 based on the setting signal e so that the rated power is obtained. Sent. This prevents an overcurrent trip. When the generated power falls below the rated power of the generator and the main steam pressure falls below the set value due to the speed control, the mode switch 1
2 is switched to the pressure controller 7 side to return to the pressure regulation control mode.

Further, even when the generated power increases and the amount of received power decreases, the mode is automatically switched to the speed control (constant power reception), so that the reverse power flow is also prevented.

As described above, in the present invention, since the pressure regulation control is basically adopted, the main steam pressure of the steam turbine 3 does not decrease, the stable operation can be performed, and the boiler can be operated. Since all generated steam can be used for power generation, the steam can be used effectively. Further, it is possible to automatically cope with any fluctuations such as fluctuations in the amount of generated steam, fluctuations in the amount of used steam, and fluctuations in the power used in the premises.

It should be noted that the present invention is not limited to the above-described embodiment, and various changes can be made without departing from the spirit of the present invention.

[0020]

As described above, according to the operation control method and apparatus of the steam turbine generator of the present invention, the steam generated in the boiler and stored in the high-pressure steam reservoir is supplied to the steam turbine through the steam line. By controlling the turbine inlet pressure by operating the turbine governor at the inlet of the steam turbine, the received power is adjusted to the set amount of received power based on pressure regulation control to generate power according to the main steam pressure. When it falls below, the power generation amount is automatically set so as to be the set received power amount and the speed control is performed.When the received power is equal to or higher than the set value and the main steam pressure is equal to or lower than the set value, the pressure is returned to the pressure control, On the other hand, when the amount of power generation exceeds the rated power of the generator, the power generation is set to the rated power of the generator, and the speed control is performed, so that the generated power is less than the rated power of the generator and the main steam pressure is less than the set value. The pressure is returned to the pressure regulation control at the point of time, so that all the steam generated by the boiler can be used for power generation, so that the steam can be used effectively. It is possible to automatically respond to fluctuations in electric power and the like without the need for manual intervention, and to prevent reverse power flow and overcurrent trip, thereby greatly reducing the burden on the operator. At the time of speed control, operate the high pressure steam condenser inlet valve in the relief line connected in the middle of the steam line,
By controlling the amount of excess steam released to the high-pressure steam condenser, it is possible to control the pressure of the high-pressure steam reservoir and to achieve excellent effects such as stable operation.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of an operation control device for a steam turbine generator according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 high-pressure steam reservoir 2 steam turbine generator 3 steam turbine 4 steam line 5 turbine governor 10 main controller 11 power controller 12 mode switch 13 relief line 14 high-pressure steam condenser 15 inlet valve 17 pressure controller b operation command signal c Detection signal g Mode switching command signal

Continuation of the front page (72) Inventor Yuji Hajiri 2-1-1, Toyosu, Koto-ku, Tokyo Ishikawajima Harima Heavy Industries Co., Ltd. Tokyo 1st Plant (72) Inventor Toshiaki Nishiyama 1-1-1, Shibaura, Minato-ku, Tokyo No. In the head office of Toshiba Corporation (72) Inventor Shinnosuke Hashimoto 66-2 Horikawa-cho, Saiwai-ku, Kawasaki-shi, Kanagawa F-term in Toshiba Engineering Corporation (reference) 3G071 AA02 AB01 BA02 BA04 BA07 BA31 DA05 DA11 EA02 FA01 FA06 GA00 HA01 HA02 HA03

Claims (3)

[Claims] When a steam generated by a boiler and stored in a high-pressure steam reservoir is supplied to a steam turbine through a steam line, a turbine governor at an inlet of the steam turbine is operated to control a turbine inlet pressure. Based on the pressure regulation control that performs power generation according to the main steam pressure, when the received power is less than the set received power amount, the power generation amount is automatically set so as to be the set received power amount, and the speed control is performed. When the received power is equal to or higher than the set value and the main steam pressure is equal to or lower than the set value, the control is returned to the pressure regulation control.On the other hand, when the power generation exceeds the generator rated power, the power generation is reduced to the generator rated power. The operation of the steam turbine generator, wherein the speed control is performed by setting, and when the generated power is equal to or less than the rated power of the generator and the main steam pressure becomes equal to or less than the set value, the control is returned to the pressure regulation control. System Your way. 2. A control device for controlling the amount of surplus steam released to the high-pressure steam condenser by operating a high-pressure steam condenser inlet valve in a relief line connected in the middle of the steam line during speed control. The operation control method for a steam turbine generator according to claim 1, wherein 3. A steam line for guiding steam generated by a boiler and stored in a high-pressure steam reservoir to a steam turbine is provided with a turbine governor at an inlet portion of the steam turbine, and is operated by a pressure controller applied to the turbine governor. A mode switching switch for switching between a command signal and an operation command signal from the power controller is operated by a mode switching command signal from the main controller. When the received power is lower than the set received power, the power generation is automatically set to the set received power and the speed control is performed. And, when the main steam pressure falls below the set value, it returns to the pressure regulation control. When the power generation exceeds the generator rated power, the power generation is reduced to the generator rated power. A function to perform speed regulation control by setting to power, and to return to pressure regulation control when the generated power is equal to or less than the generator rated power and the main steam pressure is equal to or less than the set value,
An operation control device for a steam turbine generator, which is provided in the main controller.