JP2001059403A - Turbine control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To compensate a desired steam flow by a valve which is opened lastly, even in the case that a steam regulating valve is failed, in a turbine control device by which a plurality of steam regulating valves is sequentially open/close-controlled. SOLUTION: This turbine control device is equipped with abnormality detecting means 35A, 35B, 35C, 35D which when the abnormality of a valve or a valve control system is detected, output an abnormality detection signal to a steam flow command signal outputting means based on opening signals outputted from opening signal outputting means 28A, 28B, 28C, 28D and opening command signals outputted from opening command signal outputting means 27A, 27B, 27C, 27D, and valve closing means 33A, 33B, 33C, 33D which are provided respectively to valve control systems and close the valve based on the abnormality detection signals outputted from the abnormality detecting means 35A, 35B, 35C, 35D. The steam flow command signal outputting means closes the valve whose abnormality is detected based on the abnormality detection signals from the abnormality detecting means 35A, 35B, 35C, 35D, and compensates the steam flow of the valve whose abnormality is detected by a valve which is opened lastly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbine control device for controlling a steam flow rate of a steam turbine in a thermal power plant or a nuclear power plant.

[0002]

2. Description of the Related Art In steam turbine control in a thermal power plant or a nuclear power plant, the amount of steam supplied to the steam supply system of the steam turbine is provided in parallel with the steam supply system of the steam turbine in accordance with a steam flow rate request signal. This is performed by sequentially controlling the opening and closing of the plurality of valves.

FIG. 8 shows a configuration of a steam turbine system in a thermal power plant. As shown in FIG.
Is connected to the inflow side of the high-pressure turbine 5 by a steam supply pipe 4 via a main steam stop valve 2 and a steam control valve (CV) 3. At the shaft end of the high-pressure turbine 5, a speed detector 6 for detecting a speed signal S2 proportional to the turbine speed is provided. The steam control valve 3 is provided with four valves in parallel with the high-pressure turbine 5 (only one valve is shown in the figure for convenience), and by controlling the opening and closing of these valves in order from the first valve to the last valve, the high-pressure turbine is controlled. It controls the steam flow rate of the steam flowing into the turbine 5.

[0004] At the outlet side of the high-pressure turbine 5, there is provided a reheater 7 for adding heat to the steam that has completed work in the high-pressure turbine 5.
An intermediate steam valve (IV) 8 for adjusting the amount of steam from the reheater 7 is connected to the inflow side of the low-pressure turbine 9 by the steam supply pipe 4. On the outflow side of the low-pressure turbine 9, there is provided a condenser 10 for condensing the steam that has finished work in the low-pressure turbine 9, and the water condensed by the condenser 10 is condensed and collected. Collected in the system. Further, a generator 10 is directly connected to a shaft end of the low-pressure turbine 9,
The generator 10 converts the mechanical output obtained by the turbine into electric energy and supplies it to the load 11.

Next, the operation of such a steam turbine system will be described. The steam generated by the steam generator 1 is
During the operation of the turbine, the steam enters and closes the steam control valve 3 via the main steam stop valve 2 which is fully open, and the amount of steam adjusted by the opening of the steam control valve 3 flows into the high-pressure turbine 5. The steam that has finished work in the high-pressure turbine 5 enters the reheater 7 and
After the heat is applied, the steam enters the intermediate steam valve 8, and the amount of steam adjusted by the intermediate steam valve 8 flows into the low-pressure turbine 9. The steam that has completed work in the low-pressure turbine 9 is supplied to the condenser 10
And discharged into the condensate system. The generator 10 directly connected to the shaft end of the low-pressure turbine 9 converts the mechanical power obtained from the low-pressure turbine 9 into electric energy and supplies the electric energy to the load 11.

Next, FIG. 9 shows a configuration of a steam control valve control device in the above-mentioned turbine system. This steam control valve control device controls the steam control valve 4 provided in parallel with the steam supply system of the high-pressure turbine 5 shown in FIG.

As shown in FIG. 9, the turbine speed detector 6
The output side of the adder 22 outputs a speed deviation signal S3 by subtracting the turbine speed signal S2 detected by the turbine speed detector 6 from the turbine reference speed S1 set by the turbine reference speed setter 21. Is provided. The output side of the adder 22 is connected to a CV coefficient unit 23 for determining the CV opening. This CV coefficient unit 23
This is for setting the ratio of the CV opening adjustment with respect to the speed deviation signal S3. This adjustment is called a CV speed adjustment rate, and is generally set so that the speed deviation signal S3 changes the valve opening by 100% at about 5% of the rated turbine speed. Then, the adder 25 adds the output set value P1 set by the operator to the output setter 24 and the output signal CV0 from the CV coefficient unit 23, and adds the CV flow command C
Output as V1. Further, the CV flow rate command CV1 is input to the flow rate distribution control unit 26. Flow distribution controller 26
Is a flow rate command CV2A, CV2B, CV2 for each valve, here, 4 valves from 3A to 3D, based on the CV flow rate command.
C, CV2D are calculated, and this is used for each flow rate opening degree converter 2.
7A, 27B, 27C and 27D. Here, since the control of each of the valves 3A to 3D is the same,
Only the valve 3A will be described, and the other will be omitted.

The CV flow rate command CV2A of the valve 3A is a steam flow rate command flowing through the steam control valve and has a value proportional to the turbine output value. Is not proportional to the opening degree characteristic of the steam control valve. That is, the turbine output value and the CV flow rate command have a non-linear relationship with the opening of the steam control valve. Therefore, the output side of the flow distribution control unit 26 has a CV flow command C
A flow / opening degree converter 27A that outputs a CV opening degree command signal CV3A proportional to V2A is connected. An adder 29A that outputs a deviation signal CV5A of the CV opening command signal CV3A and the CV actual opening signal CV4A of the steam control valve 3A detected by the valve opening detector 28A is provided in the flow / opening converter 27A. It is connected.

The output of the adder 29A has a deviation signal CV
An amplifier 30A that proportionally amplifies 5A and outputs each as a signal CV6A is connected. The output side of the amplifier 30A is connected to an electric / hydraulic converter 31A that outputs an electric signal CV6A as a hydraulic signal CV7A. The electric / hydraulic converter 31A opens the valve when the electric signal has a positive polarity and closes the valve when the electric signal has a negative polarity, and changes the opening / closing speed of the valve in proportion to the magnitude of the electric signal to generate the hydraulic signal CV7A. Output. The output side of the electric / hydraulic converter 31A is connected to a valve operator 32A that converts the hydraulic signal CV7A into a mechanical position signal CV8A and controls the opening of the valve 3A. That is, the above-described configuration provides the deviation signal C
The closed loop control is such that V5A and CV6A become zero.

[0010] Further, a rapid closing operation device 34A for converting the rapid closing detection signal CV9A output from the rapid closing detector 33A into a hydraulic rapid closing detection signal CV10A and outputting the same is connected to the output side of the rapid closing detector 33A. Have been. A valve 3A is provided on the output side of the quick closing operation device 34A based on the hydraulic quick closing detection output CV10A.
A valve operating device 32A for rapidly closing D is connected.

Next, the operation of the steam control valve control device will be described with reference to FIGS. The speed deviation signal S3 obtained by subtracting the turbine speed signal S2 detected by the turbine speed detector 6 from the turbine reference speed signal S1 set by the turbine reference speed setter 21 is CV
It is input to the coefficient unit 23. When the speed deviation signal S3 is about 5% of the rated turbine speed and the valve opening is 100
%, And outputs the signal CV0.

The output value P1 from the output setting unit 24 is
And the output signal CV0 from the CV coefficient unit 23 are
And output as the CV flow rate command CV1. Further, the CV flow rate command CV1 is input to the flow rate distribution control unit 26. As shown in FIG. 10, the flow distribution control unit 26 includes:
A function generator 26 in which the steam control valve 3A, the steam control valve 3B, the steam control valve 3C, and the steam control valve 3D are sequentially opened.
Since A, 26B, 26C, and 26D are provided, the CV flow rate command for each valve is also CV2A, CV2B, CV2C, C
Open commands are output in the order of V2D. In addition, as shown in FIG. 11, in a normal plant, up to 95% of the rated output can be obtained by opening only the steam control valves 3A, 3B, 3C, and the steam control valve 3D is slightly opened (about several%). 95% -1
The capacity of the steam control valve is designed so that an output of 00% is obtained.

CV opening command CV3A and steam control valve 3A
CV actual opening CV4A detected by the valve opening detector 28A of FIG.
Is input to the adder 29A, and the difference between the two signals is output as the difference signal CV5A. This deviation signal CV5A
Is proportionally amplified by the amplifier 30A, and then the signal CV6
A is output as A and input to the electric / hydraulic converter 31A. The electric / hydraulic converter 31A converts the electric signal into a hydraulic signal C.
Convert to V7A and output. At this time, when the electric signal has a positive polarity, the valve is opened, and when the electric signal has a negative polarity, the valve is closed. By changing the opening / closing speed of the valve in proportion to the magnitude of the electric signal, the hydraulic signal CV7 is changed.
A is output. The hydraulic signal CV7A is transmitted to the valve operating device 32.
A converts it into a machine position signal CV8A and outputs it.
Adjust the opening of the steam control valve 3A. In addition, steam control valve 3
When it becomes necessary to fully close A at a high speed, the sudden closing detector 33A outputs a sudden closing electric signal CV9A to excite a solenoid valve incorporated in the sudden closing operation device 34A to thereby control the steam control valve. 3A is fully closed rapidly.

[0014]

However, in the above-described configuration, the steam control valve or each of the steam control valves is controlled when a plurality of valves are sequentially opened and closed to obtain a desired output required by the plant. When a failure occurs in the control system of the steam control valve, a desired output cannot be obtained, and there is a possibility that a trouble occurs in plant operation. The present invention has been made in view of the above circumstances, and even when a failure occurs in the steam control valve or the system of each steam control valve, the steam control that is finally opened instead of the valve of the failed system. An object of the present invention is to provide a turbine control device capable of compensating an opening degree by a valve.

[0015]

According to the first aspect of the present invention, there is provided a control system for controlling a steam flow rate of steam supplied to a turbine. Steam flow command signal output means for outputting a steam flow command signal for each valve to flow to the turbine in order to sequentially control the opening and closing of a plurality of valves provided in parallel for each valve in accordance with the steam flow request signal; An opening command signal output means for outputting an opening command signal for each valve based on the steam flow command signal of the valve, and an opening signal provided by a control system for each valve to detect the actual opening of each valve. Output signal outputting means for outputting the opening command signal output from the opening command signal output means and the opening signal output from the opening signal output means provided in the control system of each valve. Valve opening / closing operator who opens / closes each valve In the turbine control device provided with, based on the opening signal output from the opening signal output means and the opening command signal output from the opening signal output means provided respectively in the control system of each valve, Abnormality detection means for detecting an abnormality of each valve or a control system of each valve, and outputting an abnormality detection signal for each valve to the steam flow rate command signal output means, and a control system for each valve, respectively. Valve closing means for closing each valve based on the output abnormality detection signal, and the steam flow command signal output means of each valve is detected by the abnormality detection means based on the abnormality detection signal from the abnormality detection means. The valve is closed by valve closing means, and the steam flow rate of the valve is compensated by the valve that is opened last. With this, among the steam control valves that sequentially open a plurality of valves based on the steam flow rate command, the valve in which the abnormality is detected by the abnormality detection signal is closed by the valve closing unit, so that even if one valve fails, Alternatively, the steam flow can be compensated by a valve that is opened last.

According to a second aspect of the present invention, in the turbine control device according to the first aspect, each valve is provided in a control system of each valve, and each valve is provided based on an abnormality detection signal output from abnormality detection means. And a steam flow command signal output means for each valve based on the abnormality detection signal from the abnormality detection means so that the steam flow rate is made equal to the steam flow rate of the valve in which the abnormality is detected. By outputting a steam flow command signal for the valve that is opened at the end, the steam flow of the valve is compensated by the valve that is opened last. Thereby, among the steam control valves that sequentially open a plurality of valves based on the steam flow command, the valve in which the abnormality is detected by the abnormality detection signal is closed by the valve closing means, and further opened at the end of the steam flow command signal output means. In order to make the steam flow command of the valve to be output the same as the steam flow rate of the valve where the abnormality is detected,
If one of the valves fails, the steam flow can be compensated by the valve that is opened last.

According to a third aspect of the present invention, in the turbine control device according to the first aspect, the steam flow command signal output means is finally opened based on an abnormality detection signal from the abnormality detection means of each valve. By providing a new function generating means for setting the function of the function generating means for outputting the steam flow command of the valve to be set to the same function as the function of the valve in which the abnormality is detected, the steam flow of the valve is finally set. It is characterized by compensation with an opened valve. With this, among the steam control valves that sequentially open a plurality of valves based on the steam flow command, the valve in which the abnormality is detected by the abnormality detection signal is closed by the valve closing unit,
Further, the function generation means in the steam flow rate command signal output means sets the steam flow rate command of the valve to be opened last to the same output as the steam flow rate of the valve in which the abnormality is detected, so that one valve fails. However, the steam flow rate can be compensated by the valve which is opened last instead.

According to a fourth aspect of the present invention, in the turbine control device according to the first aspect, the steam flow command signal output means is finally opened based on an abnormality detection signal from the abnormality detection means of each valve. By providing switching means for switching the steam flow command of the valve to be switched to the steam flow command of the valve in which an abnormality is detected, the steam flow of the valve is compensated by the valve that is opened last. Thus, among the steam control valves that sequentially open a plurality of valves based on the steam flow command, the valve in which the abnormality is detected by the abnormality detection signal is closed by the valve closing device, and further, the switching device in the steam flow command signal output device is switched. Therefore, the steam flow command of the valve that is opened last is switched to the steam flow command of the valve in which an abnormality is detected, so even if a failure occurs in one valve, the steam flow rate is changed by the valve that is opened last instead. Can compensate.

According to a fifth aspect of the present invention, in the turbine control device according to the first aspect, the steam flow command signal output means is finally opened based on an abnormality detection signal from the abnormality detection means of each valve. By providing an adding means for adding the steam flow command of the valve in which the abnormality is detected to the steam flow command of the valve to be operated, the steam flow of the valve is compensated by the valve that is opened last. Thus, among the steam control valves that sequentially open the plurality of valves based on the steam flow command, the valve in which the abnormality is detected by the abnormality detection signal is closed by the valve closing device, and the adding device in the steam flow command signal output device is further closed. By adding the steam flow command of the valve in which the abnormality was detected to the steam flow command of the fourth valve, even if one valve fails, the steam flow is compensated by the valve that is opened last instead. can do.

According to a sixth aspect of the present invention, in the turbine control device according to the first aspect, each of the valves for converting the opening signal detected by the opening detecting means of each valve into a steam flow signal is provided. Opening flow rate conversion means, first addition means for adding the steam flow rate signal corresponding to each valve output from the opening flow rate conversion means for each valve, and a first flow rate signal from the total steam flow demand signal of the steam flow rate signal for each valve. A second adding means for detecting a difference between the signals corresponding to the steam flow rate signals output from the adding means, and a second adding means for outputting the steam flow rate command signal of the last valve opened from the steam flow rate command signal output means of each valve. Third to add the signal from
An addition unit is provided, and the addition of the signal output from the second addition unit to the third addition unit is performed only when the abnormality detection signal output from the abnormality detection unit operates. With this, among the steam control valves that sequentially open a plurality of valves based on the steam flow command, the valves in which the abnormality is detected by the abnormality detection signal are closed by the valve closing means, and the total steam flow of the steam flow signal of each valve is further closed. The difference between the request signal and the total flow rate actually flowing through each valve is obtained, and this difference is added to the steam flow command of the valve that is opened last. Even if a plurality of valves have an abnormality until the maximum opening degree is reached, the insufficient flow rate can be compensated by the valve that is opened last.

According to a seventh aspect of the present invention, in the turbine control device according to the first aspect, the opening signals of the respective valves for converting the opening signals detected by the opening means of the respective valves into a steam flow signal. A flow rate converting means for adding a steam flow rate signal corresponding to each valve output from the opening degree flow rate converting means for each valve.
An adding means, and a second adding means for detecting a difference between a signal corresponding to a steam flow signal output from the first adding means from a total steam flow request signal of the steam flow signal of each valve, and a steam flow rate of a valve which is opened last. Only the command is controlled by using the output signal from the second adding means instead of the output from the steam flow rate command signal output means to control the last valve to be opened. With this, among the steam control valves that sequentially open a plurality of valves based on the steam flow command, the valves in which the abnormality is detected by the abnormality detection signal are closed by the valve closing means. The difference between the request signal and the total flow actually flowing through each valve is determined, and this difference is used as the steam flow command for the valve that is opened last. Until the maximum opening is reached, the insufficient flow can be compensated by the valve that is opened last even if an abnormality occurs in a plurality of valves.

According to an eighth aspect of the present invention, in the turbine control device according to any one of the first to seventh aspects, the number of valves provided in parallel on the steam inflow side of the turbine is four. When the detection means detects abnormality of the first to third valves, the steam flow rate of the valve is compensated by the fourth valve which is opened last. This allows
Among the steam control valves that are sequentially opened from the first valve to the fourth valve based on the steam flow command, the valve in which the abnormality is detected is closed by the valve closing means by the abnormality detection signal, and the last valve is replaced with the valve in which the abnormality is detected. The steam flow rate can be compensated by the fourth valve which is opened at the end.

[0023]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a configuration of a turbine control device according to a first embodiment of the present invention. In addition,
The same parts as those in FIG. 9 are denoted by the same reference numerals, and description thereof will be omitted. In the present embodiment shown in FIG. 1, the control system of the steam control valve 3A includes an opening signal CV4A indicating the actual opening of the steam control valve 3A detected by the valve opening detector 28A and a valve 3A. Based on the opening command signal CV3A, the valve 3A
Alternatively, when an abnormality is detected in the control system of the valve 3A, the abnormality detection signal F
Valve abnormality detector 35A that outputs 1A to sudden closing detector 33A
Is provided. The steam control valves 3B, 3C, 3D
Are similarly provided. Here, taking the steam control valve 3A as an example, the valve abnormality detectors 35A, 35A
The detection of abnormality in B, 35C, and 35D is based on the opening signal CV4A indicating the actual opening of the valve 3A, that is, the opening of the steam control valve 3A following the opening command signal CV3A for the steam control valve 3A. This is done when it stops working.
An abnormality detection signal F1A is provided on the output side of the valve abnormality detector 35A.
Is connected to a quick-close detector 33A that outputs a quick-close detection signal CV9A based on the above.

Further, as shown in FIG. 2, the flow rate distribution controller 26 controls the valve abnormality detectors 35A, 35B, 35C based on the abnormality detection signals F1A, F1B, F1C and the steam flow request signal CV1. A function generator 26E is provided for setting a flow distribution function similar to the flow distribution function 26A, 26B, or 26C of the valve system in which an abnormality is detected in the flow distribution function unit 26D of the steam control valve 3D. FIG. 3 shows the input / output characteristics of function generator 26E in the present embodiment. When this function generator receives the abnormality detection signal F1A, the same function as the flow distribution function 26A is applied to the flow distribution function unit 26D.
Similarly, when the abnormality detection signal F1B is input, the same function as the flow distribution function 26B is input to the flow distribution function unit 26D. Similarly, when the abnormality detection signal F1C is input, the flow distribution function 26
It has the characteristic of setting the same function as C in the flow distribution function unit 26D.

Next, the operation of the steam turbine control device according to the present embodiment will be described. In the steam turbine control device of the present embodiment, the steam control valve 3A, the steam control valve 3B, and the steam control valve 3C are sequentially controlled to open to a desired steam flow rate up to 95% of the plant output rating. Now, when a failure occurs in the steam control valve 3A or the valve system that controls the steam control valve 3A, the abnormality detection signal F1 is output from the valve abnormality detector 35A.
A is output. The abnormality detection signal F1A output from the valve abnormality detector 35A is input to the sudden closing detector 33A, and the sudden closing detector 33A outputs the sudden closing detection signal CV9A to the sudden closing operation device 3A.
Output to 4A. The quick closing operation device 34A outputs the quick closing detection signal C
V9A is converted into a hydraulic rapid closing detection signal CV10A and output to the valve operating device 32A. Then, the valve operating unit 32A fully closes the steam control valve 3A based on the hydraulic rapid closing detection signal CV10A.

Further, the abnormality detection signal F1A is output to the flow distribution controller 26. The function generator 26E in the flow distribution controller 26 sets the same function as the flow distribution function 26A in the flow distribution function 26D in response to the input of the abnormality detection signal F1A, and outputs the steam control valve 3 output from the flow distribution function 26D.
The CV flow command CV2D for controlling D is the same flow command as the CV flow command CV2A for controlling the failed steam control valve 3A.

As a result, the steam control valve 3D can obtain the required opening of the steam control valve 3A whose valve opening is fully closed due to a failure. The case where a failure has occurred in the steam control valve 3A or the valve system that controls the steam control valve 3A has been described above, but the steam control valve 3B or the steam control valve 3B has been described.
Control system and steam control valve 3C or steam control valve 3
The same operation is performed when a failure occurs in the valve system that controls C.

Therefore, according to the turbine control device of the present embodiment, the steam control valves 3A, 3B, 3C or the steam control valves 3A, 3B, 3C are controlled within the operating range up to 95% of the plant output rating. Even when a failure occurs in the valve system, the opening degree can be compensated by the steam control valve 3D excluding the valve of the failed system. Therefore, the steam flow rate of the turbine can be secured, and as a result, the plant operation can be continued without changing the plant output. In addition, plant output 95% to 100
% And the steam control valves 3A, 3B, and 3C become abnormal when the steam control valve 3D is operated in an open state, the turbine output can be reduced by 5% and maintained at 95%. Reduction can be minimized.

FIG. 4 shows a configuration of a flow distribution controller 26 in a turbine control device according to a second embodiment of the present invention. Except for the configuration inside the flow distribution controller 26, it is the same as the first embodiment shown in FIG. 1, and the same parts as those in FIG. In the present embodiment shown in FIG. 4, the flow distribution controller 26 has the switch F1 operated by the abnormality detection signals F1A, F1B, F1C output from the valve abnormality detectors 35A, 35B, 35C.
AS1, F1BS1, F1CS1 and F1AS2, F1
BS2, F1CS2 are newly provided.

The circuit that outputs the CV flow rate command CV2D for controlling the steam control valve 3D normally outputs a signal from the flow rate distribution function unit 26D, but when the abnormality detection signal F1A is input, Switch F1AS1 is closed and F
1AS2 opens, the signal from the flow distribution function unit 26D is disconnected, and the signal from the flow distribution function unit 26A is output. Similarly, when the abnormality detection signal F1B is input, the switch F1BS1 is closed and F1BS2 is opened, and the abnormality detection signal F
When 1C is input, the switch F1CS1 is closed and F1CS1 is closed.
CS2 is opened, the signal from the flow distribution function unit 26D is disconnected, and the signal from the flow distribution function unit 26B or 26C is output.

Next, the operation of the steam turbine control device according to the present embodiment will be described. In the steam turbine control device of the present embodiment, the steam control valve 3A, the steam control valve 3B, and the steam control valve 3C are sequentially controlled to open to a desired steam flow rate up to 95% of the plant output rating.

If a failure occurs in the steam control valve 3A or the valve system that controls the steam control valve 3A, the valve abnormality detector 3
The abnormality detection signal F1A is output to the flow distribution controller 26 from 5A. In the flow distribution controller 26, the abnormality detection signal F1
The CV flow command CV2D, which was the output from the normal flow distribution function 26D by the input of A, is switched to the output from the flow distribution function unit 26A, and the failed steam control valve 3A
Is the same as the CV flow command CV2A for controlling the flow rate command.

As a result, the steam control valve 3D can obtain the originally required opening of the steam control valve 3A whose valve opening is fully closed due to a failure. The case where a failure has occurred in the steam control valve 3A or the valve system for controlling the steam control valve 3A has been described above. However, the steam control valve 3B or the valve system for controlling the steam control valve 3B and the steam control valve 3C or the steam control valve are described. The same operation is performed when a failure occurs in the valve system that controls 3C. Therefore, according to the turbine control device of the present embodiment, the same effects as those of the first embodiment can be obtained.

FIG. 5 shows a configuration of a flow distribution controller 26 in a turbine control device according to a third embodiment of the present invention. Except for the configuration inside the flow distribution controller 26, it is the same as the first embodiment shown in FIG. 1, and the same parts as those in FIG. In the present embodiment shown in FIG. 5, the flow distribution controller 26 has a switch F1 operated by abnormality detection signals F1A, F1B, F1C output from the valve abnormality detectors 35A, 35B, 35C.
AS1, F1BS1, F1CS1 and switch F1AS1
From the flow distribution function unit 26A via the switch F
A signal from the flow distribution function unit 26B via the 1BS1,
An adder 26F for adding a signal from the flow distribution function unit 26C via the switch F1CS1 and a signal from the flow distribution function unit 26D is newly provided.

The CV for controlling the steam control valve 3D
Since the circuit that outputs the flow command CV2D1 normally outputs the same signal as the CV2D signal from the flow distribution function unit 26D, the switch F1AS1 operates when the abnormality detection signal F1A is input. , Flow distribution function unit 2
The CV2D signal from the 6D is added to the CV2A signal from the flow distribution function unit 26A by the adder 26F, and the CV2D signal is added.
Output as 1. Similarly, when the abnormality detection signal F1B is input, the switch F1BS1 sets the abnormality detection signal F1C
Is input, the switch F1CS1 operates, and the CV2D signal from the flow distribution function unit 26D is added to the CV2B or CV2C signal from the flow distribution function unit 26B or 26C, and is output as a CV2D1 signal. I do.

Next, the operation of the steam turbine control device according to the present embodiment will be described. When a failure occurs in the steam control valve 3A or the valve system that controls the steam control valve 3A, an abnormality detection signal F1A is output from the valve abnormality detector 35A to the flow distribution controller 26. In the flow distribution controller 26, the CV flow command CV2D1, which was only the output from the normal flow distribution function 26D due to the input of the abnormality detection signal F1A, is added with the CV2A signal output from the flow distribution function unit 26A to add the steam control valve 3D. Is output as CV2D1.

Thus, the steam control valve 3D can obtain the originally required opening of the steam control valve 3A whose valve opening is fully closed due to a failure. The case where a failure has occurred in the steam control valve 3A or the valve system for controlling the steam control valve 3A has been described above. However, the steam control valve 3B or the valve system for controlling the steam control valve 3B and the steam control valve 3C or the steam control valve are described. The same operation is performed when a failure occurs in the valve system that controls 3C. Therefore, according to the turbine control device of the present embodiment, the same effects as those of the first embodiment can be obtained.

FIG. 6 shows a configuration diagram of a flow rate calculation unit 400 newly provided in the turbine control device according to the fourth embodiment of the present invention. Here, the flow rate calculation unit includes a flow rate distribution control unit 26 and a flow rate / opening degree converter 27 of the turbine control device shown in FIG.
D is newly provided, and the other configuration is the same as that of the first embodiment shown in FIG. 1. The same parts as those in FIG. . In the present embodiment shown in FIG. 6, the valve opening detectors 28A, 28
B, CC4A, CB4B, and CV4C output from the opening signals CV4B and CV4C, the opening flow rate converters 40A, 40B, and 4 detect the signal corresponding to the steam flow rate flowing through each valve.
0C and the flow rate corresponding signals CV20A, CV20B, C of the valves output from the flow rate converters 40A, 40B, 40C.
An adder 41 for adding V20C and a CV flow rate command CV1
An adder 42 for calculating a deviation signal of the output signal CV21 from the adder 41; a flow deviation signal CV22 output from the adder 42; and a distribution function unit 26D in the flow distribution controller 26.
An adder 43 for adding the CV2D signal from the controller, and a switch F1 operated by abnormality detection signals F1A, F1B, F1C output from the valve abnormality detectors 35A, 35B, 35C.
AS1, F1BS1, and F1CS1 are converted to a flow rate calculation unit 400
As a new configuration. Here, the flow rate calculation unit 400 performs a calculation process on the CV2D signal from the flow rate distribution controller 26D based on the values of the opening degree signals CV4A, CV4B, and CV4C to thereby obtain the steam flow rate of the steam control valve 3D ( Shortage).

Next, the operation of the steam turbine control device according to the present embodiment will be described. In the steam turbine control device of the present embodiment, the steam control valve 3A, the steam control valve 3B and the steam control valve 3C are sequentially controlled to open to a desired steam flow rate up to 95% of the plant output rating.

If a failure occurs in the steam control valve 3A or the valve system for controlling the steam control valve 3A, the valve abnormality detector 3
5A outputs an abnormality detection signal F1A. The abnormality detection signal F1A output from the valve abnormality detector 35A is input to the sudden closing detector 33A, and the sudden closing detector 33A outputs the sudden closing detection signal CV9A to the sudden closing operation device 34A. The quick closing operator 34A converts the quick closing detection signal CV9A into the hydraulic quick closing detection signal CV9A.
It is converted to V10A and output to the valve operating device 32A. Then, the valve operating unit 32A fully closes the steam control valve 3A based on the hydraulic rapid closing detection signal CV10A.

Further, the flow rate calculation unit 400 newly provided this time uses the opening degree flow rate converters 40A, 40B, 40C.
, The flow rate signals CV20A, CV20B, CV20C of the valves output from the opening degree flow rate converters 40A, 40B, 40C are added by the adder 41, and the signals from the first valve are added. A signal corresponding to the total steam flow rate flowing through the third valve can be detected. Further, the adder 41 calculates the deviation between the CV flow rate command CV1 and the signal CV21 corresponding to the total steam flow rate of the first valve to the third steam flow rate to obtain a desired steam flow rate to be flowed by the steam control valves 3A, 3B, 3C, 3D. Shortage is required.

Further, the insufficient steam flow rate signal CV22 is added to the adder 43 via the switches F1AS1, F1BS1, F1CS1 operated by the abnormality detection signals F1A, F1B, F1C output from the valve abnormality detectors 35A, 35B, 35C. And is added to the CV flow rate command CV2D of the steam control valve 3D, and is input to the flow rate opening converter 27D as the CV flow rate command CV23. Thereby, the shortage with respect to the desired steam flow rate can be compensated by the steam control valve 3D.

Therefore, according to the turbine control device of the present embodiment, the steam control valves 3A, 3B, 3C or the steam control valves 3A, 3B, 3C are controlled in the operating range up to 95% of the plant output rating. Even when a failure occurs in the valve system, the valve of the failed system can be excluded and compensated by the steam control valve 3D, so that the steam flow rate of the turbine can be secured, and as a result, the plant output can be reduced. The plant operation can be continued without changing. Further, in the above description, the plant output is 95% of the rated value.
As described above, according to the present embodiment, even if the plant output is exceeded or there are a plurality of failed valve systems, it is possible to compensate until the valve opening of the steam control valve 3D reaches the maximum opening. become.

FIG. 7 shows a configuration of a flow distribution controller according to a fifth embodiment of the present invention. The flow distribution controller 2
6 is the same as the first embodiment shown in FIG. 1, and the same parts as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted. In the present embodiment shown in FIG. 7, the abnormality detection signals F1A, F1B, F1
A CV flow command circuit 410 that operates according to the input of C is newly provided. The CV flow rate command circuit 410 generates an opening signal CV output from the valve opening detectors 28A, 28B, 28C.
Opening flow rate converters 40A, 40B, 40 for detecting signals corresponding to steam flow rates flowing from 4A, CV4B, CV4C through each valve.
C and the flow rate equivalent signals CV20A, CV20B, CV of the respective valves output from the opening degree flow rate converters 40A, 40B, 40C.
It comprises an adder 51 for adding 20C and an adder 52 for calculating a deviation signal of the output signal CV31 of the adder 51 from the CV flow rate command CV1.

Normally, a signal CV2D from the flow distribution function unit 26D is output as a CV flow command for controlling the steam control valve 3D, but the abnormality detection signals F1A, F1
When B and F1C are input, the CV flow rate command circuit 41
0 operates and outputs the signal CV32 in place of the signal CV2D.

Next, the operation of the steam turbine control device according to the present embodiment will be described. In the steam turbine control device according to the present embodiment, the steam control valve 3A, the steam control valve 3B, and the steam control valve 3C are sequentially opened to flow a desired steam flow rate. Now, when a failure occurs in the steam control valve 3A or the valve system that controls the steam control valve 3A, the valve abnormality detector 35A
Outputs an abnormality detection signal F1A. Valve abnormality detector 3
Abnormal detection signal F1A output from 5A is input to sudden closing detector 34A, and sudden closing detector 33A outputs sudden closing detection signal C
V9A is output to the rapid closing device 33A. Quick closing actuator 34
A indicates that the sudden closing detection signal CV9A is the hydraulic sudden closing detection signal CV1.
The value is converted to 0A and output to the valve operating device 32A. Then, the valve operating unit 32A fully closes the steam control valve 3A based on the hydraulic rapid closing detection signal CV10A.

Further, a newly provided CV flow rate command circuit 410 for determining the opening degree of the steam control valve 3D is used. The opening degree flow rate converters 40A, 40B, 40C correspond to steam flow rate signals flowing from the first valve to the third valve. And the opening degree flow converter 40
A, 40B, and 40C output the first to third flow rate equivalent signals CV20A, CV20B, and CV20C of the third valve by the adder 51 to add the steam control valve 3A, which flows from the first valve to the third valve. A signal corresponding to the total steam flow rate of the sum of 3B and 3C can be detected. Further, the adder 51 calculates a deviation between the CV flow rate command CV1 and the signal CV31 corresponding to the total steam flow rate of the steam control valves 3A, 3B, 3C to obtain a desired steam flow to be flowed by the steam control valves 3A, 3B, 3C. Shortage is required.

Further, the flow distribution function unit 26D of FIG. 1 is stopped, and the CV flow command C obtained by the flow distribution function unit 26D is obtained.
V2D and the output signal CV obtained by the adder 52.
By setting 32 to the CV flow rate command of the steam control valve 3D, the shortage of the steam flow obtained by the steam control valve 3A, the steam control valve 3B, and the steam control valve 3C for the desired steam flow is determined by the steam control valve 3D. Obtainable. In other words, the steam control valve 3D can obtain the shortage of the steam flow which should be originally obtained by each of the steam control valves 3A, 3B, 3C.

According to the turbine control device of this embodiment, the steam control valve 3A, 3B, 3C or the steam control valve 3
Even if a failure occurs in the valve system controlling A, 3B, 3C, the steam control valve 3 is excluded by excluding the valve of the failed system.
D can compensate until the valve opening of the steam control valve 3D reaches the maximum opening, so that a desired steam flow rate of the turbine can be secured, and as a result, plant operation can be performed without changing the plant output. Can continue.

In the above-described embodiment, the case where the number of steam control valves is four is described, but the present invention can be similarly applied to a case where a plurality of steam control valves are used. Further, as the valve closing means, for example, a sudden closing detector or a sudden closing operating device is used in consideration of a case where the valve is rapidly closed, but the present invention is not limited to this.

[0051]

According to the first to eighth aspects of the present invention, when one valve fails in the range of 95% or less of the plant output rating which does not require control of the last valve to be opened. The operation of the plant can be continued without changing the turbine output. Furthermore, according to the configuration of claim 6 or claim 7, even if the plant output exceeds 95% of the rated value or an abnormality occurs in a plurality of valve systems by the means described in each of the above, the valve is opened last. Until the valve reaches the maximum opening, the valve that is opened last can compensate for the insufficient flow rate, so that the operation of the plant can be continued without changing the turbine output.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a turbine control device according to a first embodiment of the present invention.

FIG. 2 is an internal configuration diagram of a flow distribution control unit according to the first embodiment of the present invention.

FIG. 3 is an input / output characteristic diagram of a function generator in the flow distribution control unit according to the first embodiment of the present invention.

FIG. 4 is an internal configuration diagram of a flow distribution control unit according to a second embodiment of the present invention.

FIG. 5 is an internal configuration diagram of a flow distribution control unit according to a third embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of a turbine control device according to a fourth embodiment of the present invention.

FIG. 7 is a configuration diagram of a turbine control device according to a fifth embodiment of the present invention.

FIG. 8 is a configuration diagram of a steam turbine system in a conventional thermal power plant.

FIG. 9 is a configuration diagram of a conventional steam control valve control device.

FIG. 10 is an internal configuration diagram of a flow distribution control unit in a conventional steam control valve control device.

FIG. 11 is an input / output characteristic diagram of a function generator in a conventional flow distribution control unit.

[Explanation of symbols]

1. Steam generator, 2. Main steam stop valve, 3, 3A, 3B,
3C, 3D: Steam control valve, 4: Steam supply pipe, 5: High pressure turbine, 6: Speed detector, 7: Reheater, 8: Intermediate steam valve, 9: Low pressure turbine, 10: Condenser, 11 ... Load, 2
1: Turbine reference speed setting device, 22: Adder, 23: C
V coefficient unit, 24: output setting unit, 25: adder, 26: flow distribution control unit, 26A, 26B, 26C, 26D: flow distribution function unit, 26E: function generator, 26F: adder, 2
7A, 27B, 27C, 27D: flow rate / opening degree converter, 2
8A, 28B, 28C, 28D ... valve opening detector, 29
A, 29B, 29C, 29D ... adders, 30A, 30
B, 30C, 30D ... amplifier, 31A, 31B, 31
C, 31D: Electric / hydraulic converter, 32A, 32B, 32
C, 32D: valve actuator, 33A, 33B, 33C, 33
D: sudden closing detector, 34A, 34B, 34C, 34D: sudden closing operation device, 35A, 35B, 35C, 35D: valve abnormality detector, 40A, 40B, 40C: opening / flow rate converter, 4
1, 42, 43... Adders, F1AS1, F1AS2, F
1BS1, F1BS2, F1CS1, F1CS2: switch, 400: flow rate calculation unit, 410: CV flow rate command circuit

Claims (8)

[Claims] 1. A control system for controlling a steam flow rate of steam supplied to a turbine, wherein a plurality of valves provided in parallel on a steam inflow side of the turbine are provided for each valve in accordance with a steam flow rate request signal. A steam flow command signal output means for outputting a steam flow command signal for each valve to flow to the turbine for sequentially controlling the opening and closing, and an opening command signal for each valve based on the steam flow command signal for each valve. Opening degree command signal output means, and opening degree signal output means provided in a control system of each of the valves to detect an actual opening degree of each of the valves and output an opening degree signal, and control of each of the valves. Valve opening / closing operation means provided in each of the systems, and performing opening / closing operations of the respective valves based on an opening command signal output from the opening command signal output means and an opening signal output from the opening signal output means. Control device provided with In the control system of each of the valves, respectively, based on the opening signal output from the opening signal output means and the opening command signal output from the opening command signal output means, each of the valves or Abnormality detection means for detecting an abnormality in the control system of each valve, and outputting an abnormality detection signal for each valve to the steam flow rate command signal output means; and the abnormality detection means provided in the control system of each valve, respectively. Valve closing means for closing each of the valves based on the abnormality detection signal output from the controller. The steam flow command signal output means for each of the valves is configured to output the abnormality detection means based on the abnormality detection signal from the abnormality detection means. The valve detected at is closed by the valve closing means,
A turbine control device wherein the steam flow rate of the valve is compensated by a valve that is opened last. 2. The turbine control device according to claim 1, further comprising: a valve closing unit provided in a control system of each of the valves to close each of the valves based on an abnormality detection signal output from the abnormality detecting unit. The steam flow command signal output means of each valve is provided based on the abnormality detection signal from the abnormality detection means, so that the steam flow is the same as the steam flow of the valve in which the abnormality is detected. A turbine control device, wherein a steam flow rate command signal is output to compensate for a steam flow rate of the valve by a valve that is opened last. 3. The turbine control device according to claim 1, wherein the steam flow command signal output means outputs a steam flow command for a valve which is opened last based on an abnormality detection signal from the abnormality detection means for each valve. By providing a new function generating means for setting the function of the function generating means to the same function as the function of the valve in which the abnormality is detected, it is possible to compensate for the steam flow rate of the valve by the valve that is opened last. Characteristic turbine control device. 4. The turbine control device according to claim 1, wherein said steam flow command signal output means outputs a steam flow command to a valve which is opened last based on an abnormality detection signal from an abnormality detection means of each valve. A turbine control device, characterized in that a switching means for switching to a steam flow command for a valve in which a pressure is detected is provided, thereby compensating for a steam flow of the valve by a valve that is opened last. 5. The turbine control device according to claim 1, wherein the steam flow command signal output means outputs an abnormality to a steam flow command of a valve that is opened last based on an abnormality detection signal from the abnormality detection means of each valve. A turbine control device, characterized in that an addition means for adding a steam flow command of a valve in which is detected is provided, thereby compensating a steam flow of the valve by a valve which is opened last. 6. The turbine control device according to claim 1, wherein the opening degree flow rate converting means for each valve converts an opening degree signal detected by the opening degree detecting means for each valve into a steam flow rate signal. First adding means for adding the steam flow signal corresponding to each valve output from the valve opening degree flow rate converting means, and the first adding means outputting from the total steam flow request signal of the steam flow signal of each valve. A second adding means for detecting a difference between the signals corresponding to the steam flow rate signals, and a signal from the second adding means to a steam flow rate command signal of the last valve to be opened which is output from the steam flow rate command signal output means of each valve. A flow rate calculation unit that includes a third addition unit that performs addition and that adds the signal output from the second addition unit to the third addition unit only when the abnormality detection signal output from the abnormality detection unit operates. Tar characterized by having provided Emissions control device. 7. The turbine control device according to claim 1, wherein the opening degree flow rate conversion means of each valve converts an opening degree signal detected by the opening degree means of each valve into a steam flow rate signal.
First adding means for adding the steam flow signal equivalent of each valve output from the opening degree flow rate converting means of each valve, and outputting from the first adding means from a total steam flow request signal of the steam flow signal of each valve. And a second adding means for detecting a difference between the signals corresponding to the steam flow rate signals to be output. Only the steam flow rate command of the valve which is opened last is replaced with the output from the steam flow rate command signal output means from the second adding means. A turbine control device comprising a circuit for controlling a valve that is opened last using an output signal. 8. The turbine control device according to claim 1, wherein four valves are provided in parallel on the steam inflow side of the turbine, and the abnormality detecting means detects the first valve from the first valve. A turbine control device, characterized in that when an abnormality of a third valve is detected, the steam flow rate of the third valve is compensated by a fourth valve that is opened last.