JPH09238499A - Serial load control device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To stably control a power generating quantity of a combined cycle power plant. SOLUTION: In this serial load control device, a power generating quantity of a combined cycle power plant comprising a first/second shaft, generated by a generator with each drive power of a gas turbine and a steam turbine, is controlled. A generation power signal 60 from each generator is totalized in an adder 3, a serial load feedback signal 4 is output to a deviation arithmetic device 5, a deviation from a serial load preset signal is obtained in the deviation arithmetic device 5, on the other hand, a steam turbine generation load signal 32 generated by each steam turbine is added in an adder 33, a serial steam turbine generation load signal 34 is output to an adder 35. A serial gas turbine generation load signal 31 generated from a serial gas turbine maximum load total sum generator 30 is added in the adder 35, a serial load preset limit signal 36 is output to an upper limit limiter 37. In the upper limit limiter 37, a serial load preset signal 2 from a serial load preset value generator 1 is compared with the serial load preset limit signal 36, a signal of larger signal level is set as a serial load preset signal 38.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a series load control device for controlling the total amount of power generation of a combined cycle power generation plant including a plurality of combined cycle power generation devices.

[0002]

2. Description of the Related Art Conventionally, a gas turbine is rotated by combustion energy of a fuel, a steam turbine is rotated based on exhaust gas discharged from the gas turbine, and a generator is rotated by rotating torque of two turbines. In a combined cycle power generation device or the like that generates electric power by using a steam turbine, the response of a steam turbine is slower than that of a gas turbine.

As shown in FIG. 1, a conventional combined cycle power generator is compressed by an air compressor 54 and a rotary shaft 52 that connects a generator 51, a steam turbine 53, an air compressor 54, a gas turbine 56 and the like. It is composed of a combustor 55 that takes in air and fuel, combusts them, and sends the combustion energy to the gas turbine 56, and a fuel control valve 62 for adjusting the fuel injected into the combustor 55.

In this combined cycle power generator,
Air is taken in and compressed by the air compressor 54 and the combustor 5
When it is sent to 5, the combustor 55 takes in the compressed air and fuel and burns them, and the combustion energy rotates the gas turbine 56. The exhaust gas discharged from the gas turbine 56 has a high temperature, and the exhaust gas is taken into the reheat steam generator 57 to generate steam from the reheat steam generator 57, and the steam is passed through the steam pipe 58. The steam turbine 53, the steam turbine 53 rotates,
As a result of the above, the rotating shaft 52 is rotated by the rotation of the gas turbine 56 and the steam turbine 53, and the rotation of the rotating shaft 52 generates electric energy (electric power) in the generator 51. The amount of this electric energy is detected as a generated power signal 60 by the generated power detector 59 and is output to the series load control device.

This series load control device is provided with a fuel control valve 62.
Is adjusted to control the power generated by a plurality of combined cycle power generators.

In this series load control device, the fuel control valve opening command signal 6 is input based on the input generated power signal 60.
3 is output to the fuel control valve 62 provided in the fuel pipe 61,
By adjusting the opening of the fuel control valve 62, the combustor 55
The amount of fuel injected into the burner 55 is adjusted to control the combustion energy in the combustor 55.

Generally, a combined cycle power generation plant operates the combined cycle power generation device as one set and operates in a plurality of sets. The set unit is generally referred to as "axis" and hereinafter referred to as "axis". It will be explained in units.

The sum of the generated power signals 60 of a plurality of axes is called a series load, and the series load control device usually controls the generated power amount of each axis based on the generated power signal 60 output from each axis. To do.

Here, a conventional series load control device will be described with reference to FIGS. 11: is a figure which shows the structure of the series load control apparatus for controlling a 2-cycle structure combined cycle power generation plant, FIG.12 (a) is the fuel control valve opening command signal output from the series load control apparatus of FIG. 63 shows the relationship between 63 and time, FIG. 12 (b) shows the relationship between the generated power signal of the combined cycle power plant and time, and FIG. 13 (a) shows the generated power signal 60 of the first axis and time. FIG. 13B shows the relationship between
The figure which shows the relationship between the electric power generation signal 60 of a shaft, and time, FIG.
(C) is a figure which shows the relationship between the series load feedback signal 4 and time.

As shown in FIG. 11, the conventional series load control device has a series load set value generator 1, an adder 3, a deviation calculator 5, and an integral element inside, and has a proportional integral deviation control ( Hereinafter, the axis load command value calculator 7 for performing PID control), this axis load command value calculator 7
It is composed of an axis load control logic 8 for each axis which performs load control based on the axis load command signal 10 output from the.

In this case, the generated power signals 60 of the first axis and the second axis are input to the adder 3, the sum of them is calculated, and the series load feedback signal 4 is output. This series load feedback signal 4
And the series load setting signal 2 generated by the series load setting value generator 1 are input to the deviation calculator 5, and the deviation between the signals is obtained and the series load deviation signal 6 is given to the axis load command value calculator 7. Is output.

When the series load deviation signal 6 is input, the axis load command value calculator 7 performs integral calculation of the load on each axis so that the deviation disappears, and the axis load command signal 10 is used to control the axis load of each axis. Output to the logic 8 and each axis load control logic 8 controls the generated power signal 60 of each axis based on the input axis load command signal 10.

At this time, the axis load command signal 10 and the generated electric power signal 60 of each axis are input to the deviation calculator 17 of each axis load control logic 8, and the deviations between them are obtained to determine the axis load deviation signal. 18 is generated and output to the fuel control valve opening command signal calculator 19, and in this fuel control valve opening command signal calculator 19, a fuel control valve opening command signal 63 is generated and output to the fuel control valve 62. To be done.

On the other hand, the large deviation detector 22 is supplied with the series load deviation signal 6, and when the value of the signal exceeds the specified value and the deviation becomes large, the large deviation signal 23 which is an output signal is turned ON. And A large deviation signal 23 is sent to the axis load command value calculator 7.
Is always input, and the integral element is accumulated inside it. Then, when the large deviation signal 23 is turned on, the calculation of the integral element is stopped.

That is, the output of the integral element in the axial load command value calculator 7 is held while the value of the series load deviation signal 6 is large.

When the deviation is large, the reason why the output of the integral element in the axial load command value calculator 7 is held is that the integral element in the axial load command value calculator 7 is unnecessary in the abnormal control state of large deviation. This is because the integration calculation of the series load deviation signal 6 is stopped, and the recovery of the series load setting signal 2 of the series load feedback signal 4 when the control is normally restored is made to follow more quickly.

By the way, when the load control of such a combined cycle power plant is carried out, the characteristics as shown in FIG. 12 occur.

That is, as shown in FIG. 3A, it is assumed that the fuel control valve opening command signal 63 has a value S1 at time T1 and starts increasing from this value S1 to reach the value S2 at time T2. When the fuel control valve opening command signal 63 is changed in this way, as shown in FIG.
0 means the value P1 to the value P3 from the time T1 to the time T3.
Draw a gentle curve to increase.

The increase of the generated power signal 60 from the value P1 to the value P3 is divided into an increase in the value P1-P2 between the times T1 and T2 and an increase in the values P2-P3 between the times T2 and T3. It can be divided into two parts.

Generated power signal 6 between times T1 and T2
Most of the increase from the value P1 of 0 to the value P2 is increased by the gas turbine 56 that reacts rapidly when the fuel control valve opening command signal 63 is increased from the value S1 to the value S2 and the fuel control valve 62 is opened. Is. That is, when the fuel control valve opening command signal 63 is increased from the value S1 to the value S2, the flow rate of the fuel injected into the combustor 55 is increased and the combustion energy of the combustor 55 is increased, which causes the gas turbine 56.
Of the generator, that is, the output of the generator, that is, the generated power signal 60 increases. At this time, the gas turbine 56 quickly responds to changes in the fuel control valve opening command signal 63, so that the response time for increasing the driving force is very fast, and the generated power signal 6
0 increases substantially in proportion to the fuel control valve opening command signal 63 between time T1 and time T2.

On the other hand, the generated power signal 6 between times T2 and T3
Most of the increase from the value P2 of 0 to the value P3 is caused by the steam turbine 53.

That is, compared with the response time between the gas turbine 56 and the generated power signal 60, the time required for the reheat steam generator 57 to generate steam with the exhaust gas discharged from the gas turbine 56 is very long. The time from when the fuel control valve opening command signal 63 increases until steam is generated in the reheat steam generator 57 and the rotation torque is given to the steam turbine 53 is increased by the fuel control valve opening command signal 63. From the time until the rotational torque is applied to the gas turbine 56.

The gas turbine 56 and the steam turbine 53
Difference in response to the generated power signal 60 is a serious problem in load control of the combined cycle power plant. As shown in FIG. 12A, on the first axis side, the generated power signal 60 at time T4 is a value P4 smaller than the maximum output load PGmax of the gas turbine 56, and as shown in FIG. Also on the second axis side, time T4
Assuming that the generated power signal 60 of the above is a value P4 smaller than the maximum output load PGmax of the gas turbine 56, as shown in FIG. 7C, the series load feedback signal 4 indicating the total load value of all series at time T4. Is twice the value P4 (2 × P
4). At time T4, it is assumed that the series load setting signal 2 is equal to the series load feedback signal 4 and thus is in a balanced state.

From this state, at time T5, when the value of the series load setting signal 2 is changed to the position of 2 × P5 between 2 × Pmax and the maximum output load of the gas turbine, 2 × PGmax, as described above, Since the response time between the turbine 56 and the generated power signal 60 is short, the generated power signal 60 of each axis in FIGS.
The maximum output load PGmax and the output load of the steam turbine at time T5 are P6, but the response time between the steam turbine 53 and the generated power signal 60 is very slow. The power signal 60 is the value P6
To a value P5 rises very slowly.

Therefore, the series load feedback signal 4 in FIG. 7C also rises very quickly from 2 × P4 to 2 × P6, but then changes very slowly from 2 × P6 to 2 × P5.

This series load feedback signal 4 is 2 × P6 to 2
Since the integral element in the axial load command value calculator 7 continues the calculation while changing very slowly to × P5, after the series load feedback signal 4 reaches 2 × P5, the series load setting signal 2
Overshoot, then undershoot, and so on.

The above is the problem in the load control of the combined cycle power generation plant caused by the difference in the responsiveness of the gas turbine 56 and the steam turbine 53 to the generated power signal 60.

Therefore, in order to solve this problem, conventionally, a large deviation detector 22 for monitoring the series load deviation signal 6 is provided to detect a large deviation when the value of the series load deviation signal 6 becomes large to some extent. The device 22 outputs a large deviation detection signal to stop the calculation operation of the integral element in the axial load command value calculator 7.

That is, after time T5 in FIG. 13, the deviation between the series load setting signal 2 and the series load feedback signal 4 becomes large. Therefore, this time is detected by the large deviation detector 22 to calculate the axial load command value. Fluctuation of the series load feedback signal 4 with respect to the series load setting signal 2 after the series load feedback signal 4 reaches 2 × P5 by stopping the integration operation in the device 7 (repeating overshoot and undershoot)
Is to reduce.

However, in this case, the large deviation detector 2
The smaller the deviation large specified value set in 2, the less the fluctuation of the series load feedback signal becomes. However, if the deviation large specified value is too small, the series load is less than twice the maximum output load of the gas turbine. Even when the set signal is small and the load control is normally performed, the series load deviation signal frequently comes into contact with the deviation large specified value of the deviation large detector 22, and the axis load command value calculation is performed each time. The output of the integral element in the device 7 is frequently held, and as a result, the controllability in controlling the series load becomes poor.

Further, as a means for controlling the series load without using the large deviation detector 22, as shown in FIG.
The axis load control logic 8 for each axis includes an axis independent load set value generator 11, a signal switcher 13 for switching between the signal from the axis independent load set value generator 11 and a series load control signal,
There is a configuration in which a series load control mode logic 15 for controlling signal switching of the signal switch 13 is provided and the control mode is switched according to the load condition of each axis.
The series load control mode logic 15 is a logic for switching the load control mode of each axis, and outputs a series load control mode signal 16. The axis single load set value generator 11 sets a target set value of the generated power signal 60 of each axis when the load control mode of each axis is the single load control mode, and sets the target set value of each axis to the axis single load. It is output as the setting signal 12. In the signal switch 13, the series load control mode signal 16 is O
When it is N, ac is connected and the series load control mode signal 1
Connect bc when 6 is OFF. A series load control mode and a single load control mode are set as the control modes, and the series load control mode logic 15 outputs a series load control mode signal 16 to switch to either one of the above signals. This series load control mode signal 16
Is a signal which is turned on when the load control mode of each axis is the series load control mode and is turned off when the load control mode is the independent load control mode. Therefore, for example, in the series load control mode,
The axis load command signal 10 is used as a target set value to control the generated electric power signal 60 of each axis. In the single load control mode, the axis single load setting value generator 11 individually provided for each axis sets the axis single load. The signal 12 is set as the target set value of the generated power signal 60 to control the load on each axis.

In the case of this series load control device, when the series load control mode logic 15 is in the series load control mode,
The series load control mode signal 16 is output to the signal switch 13 in the ON state, and the signal switch 13 outputs the shaft load command signal 10 to the deviation calculator 17 as the shaft load setting signal 14.

Here, when the series load control mode logic 15 is set to the independent load control mode in order to change the load state, the series load control mode signal 16 is output in OFF, and the axis independent load setting signal 12 is output. The load setting signal 14 is output to the deviation calculator 17.

The shaft load setting signal 14 and the generated electric power signal 60 for each shaft are input to the deviation calculator 17, the deviation between them is calculated, and the shaft load deviation signal 18 is output. This shaft load deviation signal 18 is a fuel control valve opening command signal calculator 19
Is input to the fuel control valve 62 as a fuel control valve opening command signal 63.

However, in this case, the deviation calculator 17
The shaft load setting signal 14 input to the shaft is switched quickly as appropriate according to the mode.
Is obtained from the amount of electric power finally generated, and the response to the mode switching is delayed after all,
The fluctuation of the series load feedback signal 4 is not improved.

[0036]

As described above, in the above-described conventional series load control device, when the large deviation detector is used, the smaller the large deviation specified value set in the large deviation detector is, the smaller the series becomes. Although the fluctuation of the load feedback signal is reduced, there is a problem that the controllability in controlling the series load is deteriorated depending on the setting.

Further, even when the control mode is switched to either the series load control mode or the individual load control mode for each axis, load control is performed based on the generated power signal which is the result of power generation at each axis. However, there is a problem that the response when the mode is switched is slow and, eventually, the controllability of the sequence load is impaired.

The present invention has been made in order to solve such a problem, and does not impair the controllability of the sequence load,
An object of the present invention is to provide a series load control device that can stably control the series load.

Another object of the present invention is to solve the above problems, and it is an object of the present invention to provide a series load control device capable of improving the responsiveness in controlling the series load.

[0040]

In order to achieve the above-mentioned object, a series load control device according to a first aspect of the present invention comprises a gas turbine supported on a rotating shaft, and a fuel burned by the gas turbine. A combustor to be driven, a fuel control valve for adjusting the flow rate of fuel injected into the combustor, a reburning steam generator for generating steam by exhaust gas discharged from the gas turbine, and a support on the rotating shaft. A plurality of combined power generators having a steam turbine driven by the steam generated by the reburnt steam generator and a generator for generating power by the power of a rotating shaft rotated by the driving force of the turbines are connected to each other. An adder that sums a plurality of generated power signals obtained from the generator of the combined power generation device, a series load set value generator that generates a predetermined target set value that is a target of the series load, and A deviation calculator that finds the deviation between the total value of the generated power signals summed by the adder and the target set value, and the deviation value output from this deviation calculator based on the deviation value output from each fuel control valve. In a series load control device having a load control system that controls the opening degree to control the power generation amount of the entire plant, a series steam turbine generated load addition means for summing the load amounts generated in the steam turbines,
A series gas turbine maximum load total generator that generates a total sum of maximum loads that can be generated in each series gas turbine, and a total value of maximum loads generated by the series gas turbine maximum load total generator, and the series steam A series load setting limit value calculating means for calculating the series load setting limit value by adding the total value of the series steam turbine generated load amounts added by the turbine generated load adding means, and the series load setting limit value generator. A predetermined series load setting value and a series load setting limit value calculated by the series load setting limit value calculating means, and an upper limit limiting means for sending the lower one to the deviation calculator as a target setting value; It is characterized by having.

According to the first aspect of the present invention, the predetermined series load set value generated by the series load set value generator by the upper limit limiting means and the series load set limit value calculated by the series load set limit value calculating means are set. Are compared, and the result of this comparison is
The lower one of them is sent to the deviation calculator as the target set value.

Therefore, even if the series load setting signal is set to a value higher than the maximum load total value of the gas turbine, the actual total value of the series load does not take a value higher than the series load setting signal. The feedback signal and the generated power signal of each axis are stably and gradually approaching the series load setting signal.

According to a second aspect of the present invention, there is provided the series load control device according to the first aspect, wherein the upper limit limiting means is the predetermined sequence load set value rather than the series load set limit value. If the predetermined series load set value is lower than the series load set limit value, the predetermined series load set value is sent to the deviation calculator as the target set value. It is characterized in that the upper limit limiter sends a value to the deviation calculator as the target set value.

In the second aspect of the present invention, in the upper limiter, when the predetermined series load set value is lower than the series load set limit value, the predetermined series load set value deviates as the target set value. It is sent to the computing unit. If the predetermined series load set value is higher than the series load set limit value, the series load set limit value is sent to the deviation calculator as the target set value.

Therefore, the series load setting signal is increased,
Even if the signal value is set to a value higher than the maximum load total value of the gas turbine, the actual total value of the series load does not take a value higher than the series load setting signal, and the series load feedback signal and each The generated power signal of the shaft becomes stable and gradually approaches the series load setting signal.

According to a third aspect of the present invention, in the series load control device according to the first aspect, the steam pressure detected at the steam inlet portion of each steam turbine is used as a steam turbine generation load. Is characterized by.

According to the third aspect of the present invention, the steam pressure is detected at the steam inlet portion of each steam turbine and used as the steam turbine generated load, so that the value can be measured without measuring the actual steam turbine generated load. It can be easily obtained.

A series load control device according to a fourth aspect of the present invention is the series load control device according to the first aspect, wherein the steam pressure at the steam outlet portion of each steam turbine is used as a steam turbine generation load. There is.

According to the fourth aspect of the present invention, the steam pressure is detected at the steam outlet portion of each steam turbine and used as the steam turbine generated load, so that the value can be measured without measuring the actual steam turbine generated load. It can be easily obtained.

According to a fifth aspect of the present invention, there is provided a series load control device according to the first aspect, wherein the steam load is a value obtained by subtracting a gas turbine generated load output from each gas turbine from each generated power signal. It is characterized by being used as a turbine generated load.

According to the fifth aspect of the invention, the actual steam turbine generated load is measured by using the value obtained by subtracting the gas turbine generated load output from each gas turbine from each generated power signal as the steam turbine generated load. The value can be easily obtained without doing.

According to a sixth aspect of the present invention, there is provided the series load control device according to the first aspect, wherein the flow rate of the fuel injected into the combustor is used as a gas turbine generation load. .

According to the sixth aspect of the invention, the flow rate of the fuel injected into the combustor is detected and used as the gas turbine generated load, so that the value can be simplified without measuring the actual gas turbine generated load. You can get it.

As a result of the above, it is possible to stably control the sequence load without impairing the controllability of the sequence load. According to another aspect of the present invention, there is provided a series load control device, which adjusts a gas turbine supported on a rotating shaft, a combustor for driving the gas turbine by burning fuel, and a flow rate of fuel injected into the combustor. A fuel control valve for, a reburning steam generator that generates steam with exhaust gas discharged from the gas turbine, a steam turbine that is supported by the rotating shaft, and is driven by the steam generated by the reburning steam generator, , Whether to control the generator that generates power by the force of the rotating shafts that are rotated by the driving force of each other's turbine and the generated electric power signal obtained from this generator or the shaft control load signal corresponding to that generator individually or in series Sequence load control mode logic for instructing, a single load setting value generator for generating a single load setting signal for independent control, and a negative load indicated by the sequence load control mode logic. There are a plurality of combined power generators having a signal switcher that outputs, as a shaft load setting signal, one of a single load setting signal generated from the single load setting value generator and a shaft load command signal according to the control state. In the connected series load control device, a load control state instructed by the series load control mode logic based on a plurality of generated power signals obtained from the generators of the combined power generators or a shaft control load signal corresponding thereto. It is characterized by comprising an axis load command calculator for generating an optimum shaft load command signal according to the above and outputting it to the signal switch.
The series load control device according to the invention of claim 8 is the load control device according to claim 7.
In the series load control device according to the description, the axis load command calculator is a zero signal generator that generates a zero signal, and a feedback from each generator according to a load control state instructed by each series load control mode logic. An input signal switcher for outputting one of the generated power signals and the zero signal generated by the zero signal generator for each combined power generation device, and the generated power signal output from the input signal switcher And an adder for summing the zero signals, a series load set value generator for generating a predetermined target set value as a target of the series load, and a total value and a target of the generated power signal and the zero signal summed by the adder Calculate the deviation from the set value,
A deviation calculator that outputs as a series load deviation signal and the series load deviation signal output from this deviation calculator are divided by the number of the combined power generators under the series load control to obtain an axis load command value, and the axis load command value is calculated. A divider for outputting to the signal switcher as a load command signal is provided.

According to a ninth aspect of the present invention, there is provided the series load control device according to the seventh aspect, wherein the axis load command calculator is a zero signal generator for generating a zero signal, and each of the series loads. According to the load control state instructed by the control mode logic, one of the shaft load setting signal fed back from each of the signal switching devices and the zero signal generated by the zero signal generator is supplied to each combined power generation device. An input signal switcher for outputting, an adder for summing the shaft load setting signal and the zero signal output from the input signal switcher, and a series load set value generator for generating a predetermined target set value as a target of series load And a deviation calculator for obtaining the deviation value between the total value of the axis load setting signal and the zero signal summed by the adder and the target setting value and outputting it as a series load deviation signal, A divider that outputs the series load deviation signal output from the difference calculator by dividing the series load deviation signal by the number of the combined power generators under series load control to obtain a shaft load command value, and outputs the shaft load command value to the signal switch as a shaft load command signal. It is characterized by having and.

According to a tenth aspect of the present invention, there is provided the series load control device according to the seventh aspect, wherein the axial load command calculator is the series load control device according to the seventh aspect. An arithmetic unit, a zero signal generator for generating a zero signal, and each generated power signal fed back from each generator and the zero signal generator according to a load control state instructed by each series load control mode logic. An input signal switcher that outputs one of the zero signals generated by each of the combined power generation devices, an adder that sums the generated power signal and the zero signal output from the input signal switcher, and a series load A series load set value generator that generates a predetermined target set value that is the target of, and the total value of the generated power signal and the zero signal summed by the adder before series load control. A first divider that divides by the number of combined power generators to calculate a series load in the single load control state for one set of the combined power generators, and a predetermined target set value generated by the series load set value generator A second divider that calculates a target load set value for one set of the combined power generators by dividing by the number of the combined power generators under the series load control, and one set of the combined power generators from the second divider Target load setting value of 1 and 1
The present invention is characterized by including a deviation calculator that obtains a deviation value from a series load in a single load control state for a set and outputs the deviation value as a shaft load command signal.

According to an eleventh aspect of the present invention, in the series load control device according to the seventh aspect, the axis load command calculator is a zero signal generator for generating a zero signal, and each of the series loads. According to the load control state instructed by the control mode logic, one of the shaft load setting signal fed back from each of the signal switching devices and the zero signal generated by the zero signal generator is supplied to each combined power generation device. An input signal switcher for outputting, an adder for summing the shaft load setting signal and the zero signal output from the input signal switcher, and a series load set value generator for generating a predetermined target set value as a target of series load And a total value of the shaft load setting signal and the zero signal summed by the adder is divided by the number of the combined generators in series load control. A first divider that calculates a series load in a single load control state for one set, and a predetermined target set value generated by the series load set value generator by the number of the combined power generators under the series load control. A second divider that divides to calculate a target load set value for one set of the combined power generator, and a target load set value for the one set of the combined power generator and one set for the single from the second divider. The present invention is characterized by including a deviation calculator that obtains a deviation value from a series load in a load control state and outputs the deviation value as a shaft load command signal.

That is, in the invention described in claims 7 to 11, since the axial load command signal can be generated without the integral element, when the value of the series load setting signal is changed, the axial load command signal also instantaneously changes. As a result, the responsiveness of sequence load control can be improved. According to a twelfth aspect of the present invention, a series load control device adjusts a gas turbine supported on a rotating shaft, a combustor that drives the gas turbine by burning the fuel, and a flow rate of the fuel injected into the combustor. A fuel control valve for, a reburning steam generator that generates steam with exhaust gas discharged from the gas turbine, a steam turbine that is supported by the rotating shaft, and is driven by the steam generated by the reburning steam generator, , Whether to control the generator that generates power by the force of the rotating shafts that are rotated by the driving force of each other's turbine and the generated electric power signal obtained from this generator or the shaft control load signal corresponding to that generator individually or in series Sequence load control mode logic for instructing, a single load set value generator for generating a single load setting signal for independent control, and the sequence load control mode logic for instructing According to the load control state, a combined power generation device having a signal switch that outputs one of a single load setting signal generated from the single load setting value generator and a shaft load command signal as a shaft load setting signal, In a plurality of connected series load control devices, an adder that sums a plurality of axis load setting signals fed back from the signal switch, and a series load set value generation that generates a predetermined target set value that is the target of the series load , A deviation calculator for obtaining a deviation between the total value of the plurality of axis load setting signals summed by the adder and a target set value, and an axis load command based on the deviation value output from the deviation calculator. A shaft load command calculator that obtains a value and outputs it as a shaft load command signal to each of the signal switching devices is provided.

According to the twelfth aspect of the present invention, since a plurality of shaft load setting signals fed back from the signal switcher are used in obtaining the shaft load command value, when the value of the series load setting signal is changed. The change in the signal returned from each combined power generation device becomes faster than when the generated power signal obtained from the generator is used (conventional), and the responsiveness of the series load control can be improved. In addition, the control gain of the axial load command value calculator can be set to a larger value than before.

[0060]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a diagram showing a hardware configuration of one combined cycle power generation device in a combined cycle power generation plant, and FIG. 2 is an example of one configuration of a series load control device for controlling the entire combined cycle power generation plant having a two-axis configuration. FIG.

As shown in FIG. 1, in each combined cycle power generator, a rotary shaft 52 connecting a generator 51, a steam turbine 53, an air compressor 54, a gas turbine 56, etc., and air compressed by the air compressor 54. And the fuel are taken in and burned, and the combustion energy is fed to the gas turbine 56.
And a fuel control valve 62 for adjusting the fuel injected into the combustor 55.

In a combined cycle power generation plant in which a plurality of such combined cycle power generation devices are installed, control is performed to adjust the opening of the fuel control valve 62 of each combined cycle power generation device to control the amount of power generation of the entire plant. A system, that is, a series load control device is provided.

As shown in FIG. 2, this series load control device includes an adder 3 for summing a plurality of generated power signals 60 output from each axis, and a predetermined target set value (series) as a target of series load. A series load set value generator 1 for generating a load setting signal 2) and a signal indicating a load amount generated in the steam turbine 53 of each shaft, that is, a plurality of steam turbine generated load signals 3
An adder 33 that sums the two to generate a series steam turbine generated load signal 34, a series steam turbine generated load signal 34 output from the adder 33, and a series load feedback signal 4
Of the sequence load setting value generator 1 that generates the sequence load setting signal 2 as the target set value of the sequence load setting signal 2 and the sequence load setting limit signal 36, whichever has a lower signal value (signal level) is selected. Output as the series load setting signal 38, the deviation between the series load setting signal 38 from the upper limit restrictor 37 and the series load feedback signal 4 from the adder 3 is calculated to obtain the series load deviation signal 6. Deviation calculator 5 to output
And an axis load command value calculator that generates an axis load command signal 10 that is a target set value of the generated power signal 60 of each axis based on the series load deviation signal 6 from the deviation calculator 5 and outputs the axis load command signal 10 to each axis. 7 and a plurality of shaft load control logics 8 for controlling the generated power signals 60 from the respective generated power detectors 59 according to the input level of the input axial load command signal 10.

The axial load command value calculator 7 has an integral element inside, and as a result of the integration calculation of the series load deviation signal 6 input by this integral element, the axial load command signal 10
Is generated. Each axis load control logic 8 obtains a deviation between the input axis load command signal 10 and the generated power signal 60 of each axis and outputs an axis load deviation signal 18 to a deviation calculator 17
And a fuel control valve opening command signal calculator 19 that generates a fuel control valve opening command signal 63 based on the input shaft load deviation signal 18 and outputs the fuel control valve opening command signal 63 to each fuel control valve 62.
In the series gas turbine maximum load signal generator 30, the maximum load value that can be generated by each of the first and second axis gas turbines 56 is set to ΡGmax, and the total value 2 × PGmax of the maximum loads for these two shafts is set. Has been done.

The upper limit limiter 37 is the steam turbine 5 of each shaft.
Steam turbine generated load signal 32, which is the load output by 3
Is input to the series load setting limit signal 36 and the series load setting signal 2 in which the total value for all axes and the total value for all axes of the maximum load that can be output by the gas turbine 56 for each axis are added. If the series load setting limit signal 36 is smaller than 2, the series load setting signal 2 is sent to the deviation calculator 5 as a target setting signal of the total value of the generated power signal 60 of each axis for all axes to set the series load. When the series load setting limit signal 36 is lower than the signal 2, the series load setting limit signal 36 is sent to the deviation calculator 5 as a target setting signal of the total value of the generated power signal 60 of each axis for all axes. It is a thing.

The steam turbine generated load signal 32 of each series described above is obtained by providing a sensor or the like at the steam inlet portion of the steam turbine 53 and detecting the steam pressure by this sensor. A sensor may be provided at the steam outlet of the steam turbine 53 to detect the steam pressure with this sensor.

Usually, a power plant is provided with a plurality of combined cycle power generators shown in FIG. 1, and a set of combined cycle power generators is generally called a “shaft”. The operation of this series load control device will be described below in units of this "axis". Further, the sum of the generated power signals 60 of each axis is called a series load, and the series load control device controls the series load by varying the generated power signal 60 of each axis.

In the case of the series load control device of this configuration example, the load generated by the steam turbine 53 such as the first shaft and the second shaft is detected by the respective sensors (steam inlet portion and steam outlet portion of the steam turbine 53). Etc.), which is output to the adder 33 as a steam turbine generated load signal 32.

In the adder 33, the respective steam turbine generated load signals 32 from the first axis and the second axis are added (total).
Then, the series steam turbine generated load signal 34 is generated and output to the adder 35.

Further, from the series gas turbine maximum load signal generator 30, an output signal (series gas turbine maximum load signal 31) of the total value 2 × PGmax of the set maximum loads for the two axes is output to the adder 35. To be done.

In the adder 35, the series gas turbine maximum load signal 31 input from the series gas turbine maximum load signal generator 30 and the series steam turbine generated load signal 34 from the adder 33 are added (summed). A series load setting limit signal 36 is generated and output to the upper limit limiter 37. Further, the series load setting value generator 1 outputs the series load setting signal 2 which is a target of the series load to the upper limiter 37.

Therefore, the series load setting signal 2 from the series load set value generator 1 and the series load setting limit signal 36 from the adder 35 are input to the upper limiter 37.

In the upper limit limiter 37, the series load setting signal 2
And the series load setting limit signal 36 are compared, and the one having the higher signal upper limit value is output to the deviation calculator 5 as the series load setting signal 38.

That is, when the sequence load setting signal 2> the sequence load setting limit signal 36, the sequence load setting signal 38 = the sequence load setting limit signal 36.

When the sequence load setting signal 2 <the sequence load setting limit signal 36, the sequence load setting signal 38 = the sequence load setting signal 2.

That is, when the level of the series load setting signal 2 which is the target of the series load from the series load setting value generator 1 is increased to increase the generated power and becomes a value higher than 2 × PGmax, the upper limit is reached. The limiter 37 selects the series load setting limit signal 36 having a signal level lower than that of the series load setting signal 2 and outputs it to the deviation calculator 5. As a result, the upper limit value of the sequence load setting signal 2 is limited by the sequence load setting limit signal 36, and the control becomes lower and lower. Therefore, the sequence load feedback signal 4 overshoots the sequence load setting signal 2. The series load feedback signal 4 rises steadily to approach the series load setting signal 2 in response to a command that increases the output of each axis, and the series load controllability is improved. It is possible to control the series load stably without damaging it.

As a result, the power generation amount can be controlled more stably in the combined cycle power generation plant than when the large deviation detector is used.

The effect of the series load control device of this structural example will be described below with reference to FIG.

FIG. 3 is a diagram showing the control characteristics of this series load control device. In FIG. 3, parts corresponding to the control characteristics (FIG. 7) of the conventional series load control device are designated by the same reference numerals, and duplicated description will be omitted.

In the figure, at time T5, when the series load setting signal 2 is changed from 2 × P4 to 2 × P5, the steam turbine generated load signal 32 shows the generated power value P6 at that time.
To total value PGmax of series load of gas turbine for each shaft
Is subtracted, and the series load setting limit signal 36 is the value P6.
And the series load setting signal 38 also has the value P6.

After time T5, the series load setting signal 38 rises along with the rise of the steam turbine generated load signal 32, so that the series load setting signal 38 and the series load feedback signal 4 change with the same value. Therefore, since the series load deviation signal 6 is always zero, the integral calculation in the axis load command value calculator 7 is not performed.

As a result, overshoot or undershoot of the series load feedback signal 4 with respect to the series load setting signal 2 does not occur.

Next, a configuration example of the second embodiment of the series load control device of the present invention will be described with reference to FIG. Note that, in FIG. 4, the same components shown in FIGS. 1 to 3 are denoted by the same reference numerals, and redundant description will be omitted.

As shown in the figure, in the series load control device of this configuration example, the generated power signals 60 from the first and second shafts and the gas turbine generation which is the output load of the gas turbine 56 of each shaft are generated. A subtractor 40 is provided which subtracts the load signal 39 to generate the steam turbine generated load signal 32 and outputs it to the adder 33.

In the series load control system of the second embodiment, the gas turbine generated load signal 39 and the generated power signal 60, which are the output load of the gas turbine 56, are output to the subtractor 40.

In the subtractor 40, the gas turbine generated load signal 39 is subtracted from the generated power signal 60 to generate the steam turbine generated load signal 32, which is output to the adder 33. Therefore, the value can be easily obtained without measuring the generated load in the actual steam turbine 53.

The other operations are the same as those of the configuration example described at the beginning.

According to the series load control system of the second embodiment, since the subtractor 40 is provided, the subtractor 40 subtracts the gas turbine generated load signal 39 from the generated power signal 60 to generate a steam turbine. Since the generated load signal 32 is obtained, the signal 32 can be simply obtained without measuring the generated load in the actual steam turbine 53, and the same effect as that of the first embodiment can be obtained. In other words, even if the series load setting signal 2 is set to a value higher than 2 × PGmax without providing a sensor or the like in the steam turbine 53, it is possible to prevent the series load feedback signal 4 from fluctuating with respect to the series load setting signal 2, and in the combined cycle power generation. The system load can be stably controlled without impairing the controllability of the system load.

The gas turbine generated load signal 39 is
In addition to the above, a sensor is provided at the fuel inlet portion of the combustor 55, the flow rate of the fuel flowing into the combustor 55 is detected by this sensor, and the detection signal is used as the gas turbine generated load signal 3
It may be nine. As a result, the gas turbine 56
It is possible to easily obtain the value without measuring the sequence load generated in.

As a result, it is possible to stably control the series load in the combined cycle power plant.

Next, a third embodiment of the series load control device of the present invention will be described with reference to FIG. FIG. 5 is a diagram showing a configuration example of the third embodiment of the series load control device of the present invention. The same components as those of the first embodiment are designated by the same reference numerals, and duplicated description will be omitted. The third embodiment shows an example of the invention described in claim 7. The series load control device of the third embodiment is not the conventional axial load command value calculator 7 that calculates an integral element,
An axis load command value calculator 72 that outputs an axis load command signal 10 only by adding and dividing the values of the signals from the axis load control logics 8 of the first axis and the second axis that change with time. have.

In the case of the series load control device of the third embodiment, the axis load command value calculator 72 has a series load setting signal 2, a series load control mode signal 16 for each axis, a generated power signal 60 for each axis, or a power generation. The axis control load signal 76, which is a signal corresponding to the power signal 60, is input.

The axis load command value calculator 72 sets an axis load command value according to the load control state of each signal fed back to itself, and outputs the axis load command signal 10 having that value to each axis load control logic 8. Output to.

In this case, the axis load command value calculator 72 first detects whether the state of each series load control mode signal 16 from each axis is the ON state or the OFF state.

If, for example, the series load control mode signal 16 from the first axis is in the ON state and the series load control mode signal 16 from the second axis is in the OFF state, the axis load control logic for the first axis is detected. 8 is in the series load control state, and the axis load control logic 8 of the second axis is in the independent load control state. In this case, therefore, the axis control load signal 76 itself is directly applied to the axis load control logic 8 of the first axis. Output as the command signal 10.

If both the series load control mode signal 16 from the first axis and the series load control mode signal 16 from the second axis are in the ON state, the axis load control logic 8 for both the first axis and the second axis is In the series load control state, in this case, the axis control load signals 76 from the first axis and the second axis are averaged (the respective axis control load signals 76 are added, and 1 /
2) is set as the axial load command value and is output as the axial load command signal 10. The averaging here means
It is a calculation such as addition, subtraction, multiplication and division of simple numbers.

Further, when both the series load control mode signal 16 from the first axis and the series load control mode signal 16 from the second axis are in the OFF state, both the first axis and the second axis are in the independent load control state. Therefore, the axis load command signal 10 is not output.

According to the series load control device of the third embodiment, the axis load command signal calculator 72 outputs the axes according to the load control states of the axis load control logics 8 for the first axis and the second axis. Since the load command value is optimized and the axis load command signal 10 is output, the axis load command signal 10 can be instantaneously output to the axis load control logic 8 without performing an integral element calculation. It is possible to improve the responsiveness of series load control.

Next, a fourth embodiment of the series load control device of the present invention will be described with reference to FIG. FIG. 6 is a diagram showing a configuration example of the fourth embodiment of the series load control device of the present invention. The same components as those of the above-described third embodiment are designated by the same reference numerals and duplicate description will be omitted. The fourth embodiment shows a specific example in which the invention described in claim 8 is applied to the axial load command signal calculator 72 of the third embodiment.

The axis load command signal calculator 72 of the series load controller of the fourth embodiment is provided in correspondence with each axis and is set to generate a "0" signal (zero signal). Zero signal generator 41, this zero signal generator 4
The contact a to which the zero signal output from 1 is input, the contact b to which the generated power signal 60 of each axis is input, and one of these contacts a and b is output as the single load control mode axis load 44. A plurality of signal switchers 43 each having a contact c for operating, and individual load control mode axis loads 44 of each axis input from each signal switcher 43 are added (totaled) and output as a single load control mode series load 46. Adder 45,
Deviation calculator 47 for subtracting the individual load control mode series load 46 from the series load setting signal 2 input from the series load set value generator 1 and outputting as the series load deviation signal 48, and the series load control mode signal 16 for each axis are input. Then, the number of axes in the series load control mode is calculated, and the result is output as the series load control mode axis number signal 50, the series load control mode axis number calculator 49, and the input series load deviation signal 48.
Is divided by the value of the series load control mode axis number signal 50 and is output as the axis load command signal 10.

In the case of the series load control device of the fourth embodiment, the zero signal generator 41 provided for each axis outputs a signal having a value of "0", that is, a zero signal 42.

The zero signal 42 and the generated power signal 60 are input to each signal switch 43, and the contacts ac of the signal switch 43 are connected when the series load control mode signal 16 is in the ON state. As a result, the zero signal 42 from the zero signal generator 41 is output as the single load control mode shaft load 44. That is, the zero signal 42 is output as the individual load control mode shaft load 44 from the signal switch 43 corresponding to the shaft in the series load control mode.

Further, the series load control mode signal 16 is turned off.
In the state, that is, in the single load control mode, the signal switch 43 is connected to its contacts bc, and the generated power signal 60 is output as the single load control mode axial load 44 and input to the adder 45. To be done.

In the adder 45, the input single load control mode shaft loads 44 are summed, and the single load control mode series load 46 that is the total value is output to the deviation calculator 47. That is, the individual load control mode series load 46
Is the sum of the generated power signals 60 from the axes whose load control mode is the single load control mode.

In the deviation calculator 47, the independent load control mode series load 46 is subtracted from the series load setting signal 2 input from the series load set value generator 1, and the result is sent to the divider 71 as a series load deviation signal 48. Is output.

On the other hand, the series load control mode axis number calculator 49
Is input with the series load control mode signal 16 of each axis,
The number of axes in the series load control mode is calculated, and the calculation result is output as the series load control mode axis number signal 50.

That is, the series load control mode axis number signal 50 is the series load control mode signal 1 for the first and second axes.
If both 6 are in the ON state, the value is "2", and if one is OFF, the value is "1".

In the divider 71, the input value of the series load deviation signal 48 is divided by the value of the series load control mode axis number signal 50 ("2" or "1"), and the result is obtained. Output as.

Therefore, when both the first axis and the second axis are in the series load control mode, the series load deviation signal 48 halved is output as the axis load command signal 10.

When the first axis is in the independent load control mode and the second axis is in the series load control mode, the series load deviation signal 48 is directly output as the axis load command signal 10.

As described above, according to the series load controller of the fourth embodiment, in the axial load command signal calculator 72,
When the series load control mode signal 16 and the axis control load signal 76 are obtained from the axis load control logic 8 of the first axis and the second axis, the axis control is performed for the series load control depending on the load control state of each axis. Since the average value of the load signal 76 is calculated and output as the shaft load command signal 10, it becomes possible to instantaneously output the shaft load command signal 10 to the shaft load control logic 8 without calculating the integral element. The responsiveness of load control can be improved.

As a result, for example, the series load setting signal 2
When changing the value of, the value of the axial load command signal 10 also changes instantaneously, and the axial load can be changed accurately in controlling the series load.

Next, a fifth embodiment of the series load control device of the present invention will be described with reference to FIG. In the fifth embodiment, the same components as those in the third embodiment are designated by the same reference numerals, and duplicated description will be omitted. The fifth embodiment is an example in which the invention described in claim 9 is specifically realized, and realizes the axial load command signal calculator 72 with a configuration different from that of the fourth embodiment.

The series load controller of the fifth embodiment is
The shaft load setting signal 14 of each axis is connected to the contact b of the signal switch 43, and the individual load control mode series load 46 is calculated based on the shaft load setting signal 14 of each axis.

In the case of the series load control device of the fifth embodiment, the shaft load setting signal 14 of each axis is connected to the contact b of the signal switch 43, instead of the generated power signal 60 from each axis. In the individual load control mode, the axis load setting signal 14 for each axis is the individual load control mode axis load 44 for each axis.
Is input to the adder 45.

Therefore, the adder 45 calculates the individual load control mode series load 46 based on the input shaft load setting signal 14 of each axis and outputs it to the deviation calculator 47. Other configurations and operations are the same as those in the fourth embodiment.

According to the series load control device of the fifth embodiment, the axis load setting signal 14 is fed back from the axis load control logic 8 of each axis to the axis load command signal calculator 72, and the load control state of each axis is changed. , The axis load command signal 10 is calculated from the axis load setting signal 14 and the axis load command signal 10 is output to the axis load control logic 8 of each axis, so that there is no integral element. Can be generated and output to the axis load control logic 8.

As a result, when the value of the series load setting signal 2 is changed, the value of the shaft load command signal 10 also changes instantaneously, and the responsiveness in controlling the series load can be improved.

Next, a sixth embodiment of the series load control device of the present invention will be described with reference to FIG. In the sixth embodiment, the same components as those in the third embodiment are designated by the same reference numerals, and duplicated description will be omitted.

The series load control device according to the sixth embodiment is
The invention according to claim 10 is applied to a plant having a three-axis configuration to realize an axial load command signal calculator 72. The deviation load calculator 7 is added to the configuration of the fifth embodiment.
5, a divider 77 as a first divider, a divider 78 as a second divider, and the like.

In the case of the series load controller of the sixth embodiment, the zero signal generator 41, to which the zero signal is set, outputs a signal having a value of zero, that is, a zero signal 42.

The signal switch 43 receives the generated power signal 60, the zero signal 42 and the series load control mode signal 16, and
When the series load control mode signal 16 is ON, the contacts ac
Are connected and the zero signal 42 is output as the individual load control mode shaft load 44, and the series load control mode signal 16 is O.
In the case of FF, the contacts bc are connected to generate the generated power signal 60.
Is output as the individual load control mode shaft load 44.

Independent load control mode of each axis The axis load 44 is
It is input to the adder 45, and the total thereof is output as the individual load control mode series load 46.

That is, the individual load control mode series load 4
6 is the sum of the generated power signals 60 of the shafts whose load control mode is the single load control mode.

The series load control mode axis number calculator 49 inputs the series load control mode signal 16 of each axis, calculates the number of axes in the series load control mode, and outputs the result as the series load control mode axis number. Output as signal 50.

That is, if all the series load control mode signals 16 of the first axis, the second axis and the third axis are ON, the value of the series load control mode axis number signal 50 becomes "3".
One of the axes is OFF and the other two are O
In the N state, the value of the series load control mode axis number signal 50 is "2".

The divider 77 inputs the series load setting signal 2 and the series load control mode axis number signal 50, divides the value of the series load setting signal 2 by the value of the series load control mode axis number signal 50 (divides). The result is the series load setting signal 7 for one axis.
Output as 4.

The single load control mode series load 46 and the series load control mode axis number signal 50 are input to the divider 78. The divider 78 sets the value of the single load control mode series load 46 to the series load control mode. It is divided (divided) by the value of the axis number signal 50, and the division result is output as a single load control mode series load 73 for one axis.

The deviation calculator 75 inputs the series load setting signal 74 for one axis and the independent load control mode series load 73 for one axis, and receives the series load setting signal 74 for one axis from the series load setting signal 74 for one axis. The load 73 is subtracted from the load control mode series load 73 and output as the shaft load command signal 10. According to the series negative control device of the sixth embodiment, in the case of a three-axis configuration plant, there are three generated power signals 60 to be fed back, and each of them can be the individual load control or the series load control. Therefore, the series load set value generator 1 outputs the target signal of the series load, that is, the series load setting signal 2 to the divider 77, divides it by the number of axes in the divider 77, and calculates the deviation 74 of the signal 74 of the division result. Bowl 75
To output the axis load command signal 10 to the axis load control logic 8 for each axis, it is possible to change the value of the series load setting signal 2 even for a plant having two or more axes. The axial load command signal 10 also changes instantaneously, and the responsiveness of series load control can be improved.

Next, a seventh embodiment of the series load control device of the present invention will be described with reference to FIG. In the seventh embodiment, the same components as those of the sixth embodiment are designated by the same reference numerals and duplicate description will be omitted. In the seventh embodiment, a shaft load command value calculator 72 is realized by applying the invention described in claim 11 to a plant having a three-axis configuration similar to that of the sixth embodiment.

The series load controller of the seventh embodiment is
The shaft load setting signal 14 of each axis is connected to the contact b of the signal switch 43, and the individual load control mode series load 46 is calculated based on the shaft load setting signal 14 of each axis.

In the case of the series load control device of the seventh embodiment, the shaft load setting signal 14 of each shaft is connected to the contact b of the signal switch 43, not the generated power signal 60 from each shaft. In the individual load control mode, the axis load setting signal 14 for each axis is the individual load control mode axis load 44 for each axis.
Is input to the adder 45.

Therefore, the adder 45 calculates the individual load control mode series load 46 based on the input shaft load setting signal 14 of each axis, and outputs it to the deviation calculator 47. The subsequent operation is similar to that of the third embodiment.

As described above, according to the series load control device of the seventh embodiment, in the plant having a three-axis configuration, the axis load command signal calculator 72 receives the axis load setting signal 14 from the axis load control logic 8 of each axis. Since the feedback is performed, the axis load command value is calculated from the axis load setting signal 14 for the series load control according to the load control state of each axis, and the axis load command signal 10 is output to the axis load control logic 8 of each axis. The axis load command signal 10 can be generated and output to the axis load control logic 8 without an integral element.

As a result, when the value of the series load setting signal 2 is changed for a plant having a structure of two or more axes, the axis load command signal 10 also changes instantaneously, and the responsiveness of series load control is improved. Can be improved.

Next, an eighth embodiment of the series load control device of the present invention will be described with reference to FIG. In the eighth embodiment, the same components as those of the conventional configuration shown in FIG. 14 are designated by the same reference numerals, and redundant description will be omitted. The eighth embodiment is an example in which the invention described in claim 12 is applied to a two-axis plant.

That is, the series load control device of the eighth embodiment is configured such that the adder 3 receives the axis load setting signal 14 for each axis instead of the generated power signal 60 for each axis. The configuration of is the same as the conventional configuration of FIG.

In the case of the series load control device according to the eighth embodiment, the adder 3 outputs to the axis load setting signal 1 for each of the first and second axes.
4 is input and the sum thereof is calculated and output as a series load feedback signal 4 to the deviation calculator 5.

The deviation calculator 5 obtains the signal deviation between the series load feedback signal 4 and the series load setting signal 2 generated by the series load setting value generator 1, and as the series load deviation signal 6, the axial load command value. Output to the arithmetic unit 7.

When this series load deviation signal 6 is input to the axis load command value calculator 7, the axis load command value calculator 7 integrates and calculates the load of each axis so as to eliminate the deviation, and outputs the axis load command signal. Axis load control logic 8 for each axis as 10
Output to

The axis load control logic 8 controls the generated power signal 60 for each axis based on the input axis load command signal 10.

At this time, the axis load command signal 10 and the generated power signal 60 of each axis are input to the deviation calculator 17 of each axis load control logic 8, and the deviations between them are calculated to obtain the axis load deviation signal. 18 is generated and output to the fuel control valve opening command signal calculator 19, and in this fuel control valve opening command signal calculator 19, a fuel control valve opening command signal 63 is generated and output to the fuel control valve 62. The fuel flow rate is adjusted,
Thereby, the steam turbine 53 and the gas turbine 5
The output of 6 is controlled.

As described above, according to the series load controller of the eighth embodiment, the axial load command value calculator 7 performs the integral element calculation, that is, the proportion integral deviation control (PID control). Adder 3
Not the generated power signal 60 from each axis, but the axis load setting signal 1
4 is fed back, the change in the series load feedback signal 4 when the value of the series load setting signal 2 is changed is the generated power signal 6
It is faster than when using 0. In addition, the control gain of the axial load command value calculator 7 can be set to a larger value than before.

As a result, the responsiveness in controlling the sequence load can be improved.

[0146]

As described above, according to the present invention, the upper limit limiting means determines the predetermined series load set value generated by the series load set value generator and the series calculated by the series load set limit value calculating means. The load setting limit value is compared and the lower one is sent to the deviation calculator as the target setting value, so even if the series load setting signal becomes a value higher than the maximum load total value of the gas turbine. , The actual total value of the series load is always lower than the series load setting signal, the series load feedback signal and the generated power signal of each axis increase steadily and gradually, and the total series load becomes the series load. The signal gradually approaches the set signal.

As a result, the series load can be stably controlled in the co-bound cycle power plant.

Further, according to the present invention, since the axis load command signal can be output to the load control system of each axis without calculating the integral element, the responsiveness in controlling the series load can be improved. .

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of a general combined cycle power plant.

FIG. 2 is a diagram showing a first embodiment of a series load control device of the present invention.

FIG. 3A is a diagram showing a relationship between a power generation signal on the first axis side and time. (B) is a figure which shows the relationship between the electric power generation signal on the 2nd axis side, and time. (C) is a figure which shows the relationship between the series load feedback signal of a series load control apparatus of FIG. 2, and time.

FIG. 4 is a diagram showing a second embodiment of a series load control device of the present invention.

FIG. 5 is a diagram showing a third embodiment of the series load control device of the present invention.

FIG. 6 is a diagram showing a fourth embodiment of the series load control device of the present invention.

FIG. 7 is a diagram showing a fifth embodiment of the series load control device of the present invention.

FIG. 8 is a diagram showing a sixth embodiment of the series load control device of the present invention.

FIG. 9 is a diagram showing a seventh embodiment of the series load control device of the present invention.

FIG. 10 is a diagram showing an eighth embodiment of the series load control device of the present invention.

FIG. 11 is a diagram showing a configuration of a related-art load control device for controlling a conventional two-axis combined cycle power plant.

12A is a diagram showing a relationship between a fuel control valve command signal output from the series load control device of FIG. 5 and time.
(B) is a figure which shows the relationship between the electric power generation signal of a combined cycle power generation plant, and time.

FIG. 13A is a diagram showing a relationship between a power generation power signal on the first axis side and time. (B) is a figure which shows the relationship between the electric power generation signal on the 2nd axis side, and time. (C) is a figure which shows the relationship between the series load feedback signal of the conventional series load control apparatus, and time.

FIG. 14 is a diagram showing another configuration of a conventional series load control device.

[Explanation of symbols]

1 ... Series load setting value generator, 2 ... Series load setting signal,
3, 45 ... Adder, 4 ... Series load feedback signal, 5 ... Deviation calculator, 6 ... Series load deviation signal, 7, 72 ... Axis load command value calculator, 8 ... Axis load control logic, 10 ... Axis load command Signal, 13, 43 ... Signal switcher, 36 ... Series load setting limit signal, 37 ... Upper limit limiter, 47, 75 ... Deviation calculator, 4
9 ... Series load control mode Number of axes calculator, 51 ... Generator, 5
2 ... rotating shaft, 53 ... steam turbine, 54 ... air compressor,
55 ... Combustor, 56 ... Gas turbine, 57 ... Reheat steam generator, 58 ... Steam pipe, 59 ... Generated power detector, 60 ... Generated power signal, 61 ... Fuel pipe, 62 ... Fuel control valve, PGm
ax ... Maximum output load of gas turbine of each axis, 71, 7
7, 78 ... Divider.

Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI technical display location // H02J 3/38 H02J 3/38 B

Claims (12)

[Claims] 1. A gas turbine supported on a rotating shaft, and a combustor for driving the gas turbine by burning fuel.
A fuel control valve for adjusting the flow rate of fuel injected into the combustor, a reburning steam generator that generates steam by the exhaust gas discharged from the gas turbine, and a reburning steam generation that is supported by the rotating shaft. A plurality of combined power generators each having a steam turbine driven by steam generated by a steam generator and a generator for generating power by the force of a rotating shaft rotated by the driving force of each turbine are connected, and the generator of each combined power generator is connected. An adder that sums a plurality of generated power signals, a series load set value generator that generates a predetermined target set value that is a target of a series load, and a plurality of generated power signals summed by the adder Based on the deviation calculator that calculates the deviation between the total value and the target set value, and the deviation value output from this deviation calculator, adjust the opening of each fuel control valve to adjust the entire plant. In a series load control device having a load control system for controlling the amount of generated electric power of the series steam turbine generated load adding means for summing the load amounts generated in the respective steam turbines, and the maximum possible generation in each series of gas turbines. A series gas turbine maximum load total generator that generates all the total loads, a total value of maximum loads generated by the series gas turbine maximum load total generator, and a series that is added by the series steam turbine generated load adding means. A series load setting limit value calculating means for calculating a series load setting limit value by adding the total value of the steam turbine generated load amount, a predetermined series load set value generated by the series load setting value generator, and the series In comparison with the series load setting limit value calculated by the load setting limit value calculating means, the lower one is sent to the deviation calculator as the target setting value. Series load control apparatus characterized by comprising a restriction means. 2. The sequence load control device according to claim 1, wherein the upper limit limiting means sets the predetermined sequence load set value when the predetermined sequence load set value is smaller than the sequence load set limit value. Is sent to the deviation calculator as a target set value, and if the predetermined series load set value is larger than the series load set limit value, the deviation calculator is set to the series load set limit value as the target set value. A series load control device characterized in that it is an upper limit limiter for sending to. 3. The series load control device according to claim 1, wherein the steam pressure detected at a steam inlet portion of each steam turbine is used as a steam turbine generation load. 4. The series load control device according to claim 1, wherein the steam pressure of a steam outlet portion of each steam turbine is used as a steam turbine generation load. 5. The series load control device according to claim 1, wherein a value obtained by subtracting a gas turbine generated load output from each gas turbine from each generated power signal is used as a steam turbine generated load. Series load control device. 6. The series load control device according to claim 1, wherein the flow rate of the fuel injected into the combustor is used as a gas turbine generation load. 7. A gas turbine supported by a rotating shaft, and a combustor for driving the gas turbine by burning fuel.
A fuel control valve for adjusting the flow rate of fuel injected into the combustor, a reburning steam generator that generates steam by the exhaust gas discharged from the gas turbine, and a reburning steam generation that is supported by the rotating shaft. Steam turbine driven by the steam generated by the generator, a generator that generates power by the power of the rotating shafts that are rotated by the driving force of the turbines, and a generated power signal obtained from this generator or a shaft control load signal equivalent to it A single load set value generator for generating a single load setting signal for independent control, and a series load control mode logic for instructing whether to independently control or serially control According to the load control state, the axis load setting signal is either one of the individual load setting signal generated from the individual load setting value generator and the axis load command signal. In a series load control device in which a plurality of combined power generators having a signal switching device for outputting are connected, based on a plurality of generated power signals obtained from the generators of the combined power generators or shaft control load signals corresponding thereto A series load control device comprising: an axis load command calculator that generates an optimum axis load command signal according to a load control state instructed by the series load control mode logic and outputs the signal to the signal switcher. . 8. The series load control device according to claim 7, wherein the axis load command calculator is responsive to a zero signal generator for generating a zero signal and a load control state instructed by each series load control mode logic. An input signal switcher for outputting, for each of the combined power generators, one of the generated power signals fed back from the generators and the zero signal generated by the zero signal generator, and the input signal switcher Adder that sums the generated power signal and zero signal output from the generator, a series load set value generator that generates a predetermined target set value that is the target of the series load, and the generated power signal summed by the adder And the deviation value between the total value of the zero signal and the target set value, and output as a series load deviation signal, and the series load deviation signal output from this deviation calculator. A series load control, characterized by comprising: a divider that divides by the number of the combined power generators under series load control to obtain a shaft load command value, and outputs the shaft load command value to the signal switch as a shaft load command signal. apparatus. 9. The series load control device according to claim 7, wherein the axis load command calculator responds to a zero signal generator that generates a zero signal, and a load control state instructed by each series load control mode logic. An input signal switcher for outputting, for each of the combined power generators, either one of a shaft load setting signal fed back from each of the signal switchers and a zero signal generated by the zero signal generator, and the input signal An adder that sums the axis load setting signal and the zero signal output from the switch, a series load set value generator that generates a predetermined target set value that is the target of the series load, and an axis that is summed by the adder. A deviation calculator that calculates the deviation value between the total value of the load setting signal and zero signal and the target setting value, and outputs it as a series load deviation signal, and the series load deviation output from this deviation calculator. The signal is divided by the number of the combined generator under the sequence load control to obtain an axial load command value, and a divider that outputs the axial load command value to the signal switch as an axial load command signal is provided. Load control device. 10. The series load control device according to claim 7, wherein the axis load command calculator is responsive to a zero signal generator for generating a zero signal, and a load control state instructed by each series load control mode logic. An input signal switcher for outputting, for each of the combined power generators, one of the generated power signals returned from the generators and the zero signal generated by the zero signal generator, and the input signal switcher Adder that sums the generated power signal and zero signal output from the generator, a series load set value generator that generates a predetermined target set value that is the target of the series load, and the generated power signal summed by the adder And the total value of the zero signals is divided by the number of the combined power generators under the series load control to calculate the series load in the single load control state for one set of the combined power generators. A first divider for output, and a predetermined target set value generated by the series load set value generator divided by the number of the combined power generators under the series load control to obtain a target load for one set of the combined power generators. A second divider for calculating a set value, and a deviation value between the target load set value for one set of the combined power generation device and the series load in the single load control state for one set from the second divider are obtained. And a deviation calculator which outputs a shaft load command signal. 11. The series load control device according to claim 7, wherein the axis load command calculator is responsive to a zero signal generator for generating a zero signal and a load control state instructed by each series load control mode logic. An input signal switcher for outputting, for each of the combined power generators, either one of a shaft load setting signal fed back from each of the signal switchers and a zero signal generated by the zero signal generator, and the input signal An adder that sums the axis load setting signal and the zero signal output from the switch, a series load set value generator that generates a predetermined target set value that is the target of the series load, and an axis that is summed by the adder. The total value of the load setting signal and the zero signal is divided by the number of the combined power generators under load control of the series, and the series of individual load control states for one set of the combined power generators. A first divider for calculating a load, and a predetermined target set value generated by the series load set value generator divided by the number of the combined power generators under the series load control for one set of the combined power generators. A second divider for calculating a target load set value, and a deviation value between the target load set value for one set of the combined power generation device and the series load in the single load control state for one set from the second divider And a deviation calculator that outputs a shaft load command signal. 12. A gas turbine supported on a rotating shaft,
A combustor that drives the gas turbine by burning the fuel, a fuel control valve that adjusts the flow rate of the fuel injected into the combustor, and a reburning steam that generates steam by the exhaust gas discharged from the gas turbine. A generator, a steam turbine supported by the rotary shaft and driven by the steam generated by the reburning steam generator, a generator that generates power by the power of the rotary shafts rotated by the driving force of the turbines, and this power generation A system load control mode logic that indicates whether to control the generated power signal obtained from the machine or its corresponding axis control load signal individually or in series, and a single load setting signal that generates a single load setting signal for independent control A load set value generator and a single load set signal generated from the single load set value generator according to a load control state instructed by the series load control mode logic. In a series load control device to which a plurality of combined power generators having one of a shaft load command signal and a signal switch that outputs a shaft load setting signal is connected, a plurality of shaft load settings fed back from the signal switch An adder that sums the signals, a series load set value generator that generates a predetermined target set value that is the target of the series load, and the total value and target set value of the multiple axis load setting signals that are summed by the adder. And a deviation calculator that calculates the deviation value of the axis load command calculation that calculates the axis load command value based on the deviation value output from this deviation calculator, and outputs it as the axis load command signal to each signal switch And a series load control device.