JP7508389B2 - Nuclear power plant output control device and output control method - Google Patents

Description

The present invention relates to an output control device and an output control method for a nuclear power plant.

Conventionally, in boiling water nuclear power plants, when a deviation occurs between the generator output target value and the current actual output value of the generator (actual generator output value), the reactor output is first adjusted according to the deviation amount, and then steam according to the reactor output is sent to the turbine to adjust the actual generator output value to the output target value. In other words, the amount of steam (hereinafter referred to as "main steam") sent out from the reactor is adjusted so that the pressure inside the reactor does not change suddenly. This is because in boiling water nuclear power plants, a sudden change in pressure inside the reactor changes the state of the steam bubbles (hereinafter referred to as voids) in the coolant, causing a change in the reactor output.

Patent Document 1 shows an example of a conventional output control device. In this example, a recirculation pump speed request signal is output based on the deviation between the generator output target and the generator's actual output value, and the reactor output is changed, and the change in reactor output changes the amount of steam generated from the reactor, which changes the turbine inlet pressure. The opening of the turbine control valve is then adjusted in proportion to the change in turbine inlet pressure, and the amount of steam to the turbine is adjusted so that the generator's actual output value matches the generator output target value. In this conventional control method, Patent Document 1 discloses an output control method in which a control generator output target value is set separately from the original generator output target value in order to suppress the control delay between the generator output target value and the generator's actual output value, thereby proactively compensating for the control delay.

In addition to conventional output control devices, Patent Document 2 also shows an example of an output control device and method that adjusts the actual output value of the generator by controlling the amount of extracted steam from the main steam. In this example, the output of the nuclear reactor is increased based on the deviation between the output target value of the generator and the actual output value of the generator, and if a deviation still occurs between the output target value of the generator and the actual output value of the generator, the amount of extracted steam from the main steam is controlled to increase the generator output.

Japanese Patent Application Laid-Open No. 64-91095 JP 2017-194312 A

The conventional techniques disclosed in Patent Documents 1 and 2 have been in demand for improving the load following performance of nuclear power plants, as explained below.

In recent years, with the goal of reducing greenhouse gas emissions, renewable energy sources such as solar and wind power have been introduced and thermal power plants have been phased out. As a result, a function known as balancing power, which adjusts the balance between power supply and demand, is becoming increasingly important, and a market for balancing power has also been established. As a result, nuclear power plants, which were previously assumed to operate at a constant rated output, are now expected to operate in a load-following manner in response to commands from the power grid.

Load following operation is classified into several categories depending on the magnitude and period of the change in output. For example, load following operation is classified into an operation called daily load following operation and an operation called frequency control operation. Daily load following operation is an operation in which the generator output is increased during the day and reduced at night in accordance with fluctuations in demand between day and night. The output change range can exceed 50% of the rated output in some cases, but as the output is changed over several hours, a fast response is not required. On the other hand, frequency control operation is an operation in which the generator output is adjusted to match the power demand that changes over a period of a few seconds to a few minutes in order to keep the frequency in the system constant. The output change range is small, at around 10%, but a fast response is required.

As mentioned above, in boiling water nuclear power plants, in order to adjust the generator output, the recirculation pump speed and control rod position are first controlled to change the reactor output, and then the amount of steam corresponding to the output is sent to the turbine to adjust the generator output. Therefore, when the rate of change of the generator output target value is large, there is a noticeable delay in the generator's actual output value. The main causes of the delay include the delay until the nuclear reaction increases when the control rod is withdrawn, and the delay until the heat generated in the fuel by the increased nuclear reaction is transferred to the coolant. If an attempt is made to suddenly change the output of the core while taking this time delay into account, the integrity of the fuel rods in the core becomes an issue, making it difficult to operate the nuclear power plant safely.

In order to expand the range of load following operation of nuclear power plants, in addition to the conventional method of increasing the power output of the reactor core, there is a method of increasing the generator output by using the steam stored in the reactor. For example, it is possible to send the required steam to the turbine by throttling the main steam extraction. However, this method is premised on the speed at which the reactor output can be increased, and if the required steam cannot be sent to the turbine by throttling the main steam extraction, the reactor output will increase suddenly, making it difficult to operate the nuclear power plant safely, just as above.

Since there is a limit to the speed at which the reactor power output can be increased, it is possible to implement load following at a nuclear power plant by throttling the main steam bleed as described above. However, throttling the main steam bleed only increases the load by a small amount, and the bleed of the feedwater heater to which the bleed is directed is closed. As a result, the increase in power output caused by throttling the bleed is only temporary, and there is an issue in that after the power output has been increased, it cannot be maintained.

The present invention has been made to solve the above-mentioned problems, and its main objective is to provide an output control device and an output control method for a nuclear power plant that improves the load following performance of the nuclear power plant.

In order to achieve the above-mentioned object, the present invention provides an output control device for a nuclear power plant, the device comprising: a turbine driven by steam generated in a nuclear reactor, a generator driven by the turbine to generate electric power, an extraction valve for adjusting the flow rate of extraction steam flowing out from the turbine, and an exhaust valve installed in an exhaust system of the turbine; a signal processing unit for controlling openings of the extraction valve and the exhaust valve based on an output target value of the nuclear power plant and an actual output value of the generator; and a reactor power setting unit for setting a reactor power of the reactor, wherein, when a load is increased on the turbine, the signal processing unit reduces the openings of the extraction valve and the exhaust valve to temporarily increase the amount of load increase on the turbine, and while the amount of load increase is being temporarily increased, the reactor power setting unit performs control to increase the reactor power.
Other means will be described later.

The present invention can improve the load following performance of a nuclear power plant.

1 is a schematic configuration diagram of a nuclear power plant equipped with an output control device according to a first embodiment. FIG. 2 is a control block diagram of an exhaust valve opening setting unit and an exhaust valve opening setting unit of the output control device according to the first embodiment. FIG. 11 is a schematic configuration diagram of a nuclear power plant equipped with an output control device according to a second embodiment. FIG. 11 is a control block diagram of a bleed valve opening setting unit, an exhaust valve opening setting unit, and a reactor of a power control device according to a second embodiment. FIG. 11 is a schematic configuration diagram of a nuclear power plant equipped with an output control device according to a third embodiment. FIG. 11 is a control block diagram of a bleed valve opening setting unit, an exhaust valve opening setting unit, and a nuclear reactor of a power control device according to a third embodiment. FIG. 11 is a schematic configuration diagram of a nuclear power plant equipped with an output control device according to a fourth embodiment.

Below, an embodiment of the present invention (hereinafter referred to as "this embodiment") will be described in detail with reference to the drawings. Note that each figure merely shows a schematic view to the extent that the present invention can be fully understood. Therefore, the present invention is not limited to the illustrated examples. In addition, in each figure, common or similar components are given the same reference numerals, and duplicate explanations thereof will be omitted.

[Embodiment 1]
<Configuration of the output control device of a nuclear power plant>
The configuration of the output control device 11 according to the present embodiment 1 will be described below with reference to Fig. 1 and Fig. 2. Fig. 1 is a schematic configuration diagram of a nuclear power plant 10 equipped with the output control device 11 according to the present embodiment 1. Fig. 2 is a control block diagram of an extraction valve opening setting unit 54 and an exhaust valve opening setting unit 55 of the output control device 11.

As shown in FIG. 1, the output control device 11 according to the first embodiment is used for a nuclear power plant 10. The output control device 11 is a device that controls the operation of the nuclear power plant 10.

The nuclear power plant 10 has a power control device 11, a nuclear reactor 12, a high-pressure turbine 14 (hereinafter sometimes simply referred to as the "turbine"), a steam separator 15, a low-pressure turbine 16, a generator 17, a low-pressure feedwater heater 18, a feedwater heater 19, a high-pressure feedwater heater 20, and a drain tank 21.

The nuclear reactor 12 is a device that has a plurality of fuel assemblies loaded therein, and gradually extracts atomic energy by controlling the rate at which a nuclear fission chain reaction proceeds by inserting and withdrawing control rods 13 into and from the fuel assemblies.
The high-pressure turbine 14 (turbine) is a rotor that rotates with the pressure of the main steam generated in the nuclear reactor 12 .
The steam-water separator 15 is a device that separates steam and water.
The low-pressure turbine 16 is a rotor that rotates by the pressure of the steam discharged from the high-pressure turbine 14 .
The generator 17 is a device that generates electric power by rotating in conjunction with the rotation of the high-pressure turbine 14 and the low-pressure turbine 16. The generator 17 is connected to the high-pressure turbine 14 and the low-pressure turbine 16 via a shaft (not shown).
The low-pressure feed water heater 18 is a device that heats the steam discharged from the low-pressure turbine 16 .
The feed water heater 19 is a device that heats the steam discharged from the low-pressure turbine 16 and heated by the low-pressure feed water heater 18 , and the steam discharged from the high-pressure turbine 14 .
The high-pressure feed water heater 20 is a heating means that heats the extracted steam (including the steam that has passed through the low-pressure turbine 16 ) flowing out from the high-pressure turbine 14 .
The drain tank 21 is a tank that temporarily stores the steam heated by the feed water heater 19 .

The reactor 12 and the high-pressure turbine 14 are connected by a pipe 31 .
In addition, the high-pressure turbine 14 and the steam separator 15 are connected by a pipe 32 .
In addition, the steam separator 15 and the low-pressure turbine 16 are connected by a pipe 33 .
In addition, the low-pressure turbine 16 and the low-pressure feed water heater 18 are connected by a pipe 34 .
In addition, the low pressure feed water heater 18 and the feed water heater 19 are connected by a pipe 35 .
In addition, the feed water heater 19 and the high-pressure feed water heater 20 are connected by piping 36.
Furthermore, the high pressure feed water heater 20 and the reactor 12 are connected by a pipe 37 .
In addition, the high-pressure turbine 14 and the high-pressure feed water heater 20 are connected by a pipe 38 .
Furthermore, the pipe 32 and the feed water heater 19 are connected by a pipe 39 .

The pipe 38 is a pipe that guides the steam that has passed through the high-pressure turbine 14 but is not supplied to the low-pressure turbine 16 to the high-pressure feed water heater 20 .
The pipe 39 is an exhaust system pipe that guides the exhaust gas, which is not supplied to the low-pressure turbine 16 and is part of the extracted steam sent from the high-pressure turbine 14 to the steam separator 15 side, to the feed water heater 19 .

The main steam generated in the reactor 12 is supplied to the high-pressure turbine 14 through piping 31. A steam control valve 40 (hereinafter sometimes simply referred to as the "control valve") is disposed in the middle of piping 31 to control the amount of main steam supplied from the reactor 12 to the high-pressure turbine 14.

Further, a bleed valve 41 is disposed in the pipe 38. The bleed valve 41 adjusts the flow rate of the bleed steam flowing out from the high-pressure turbine 14.
An exhaust valve 42 is disposed in the pipe 39. The exhaust valve 42 adjusts the flow rate of the exhaust of the extracted steam flowing out from the high-pressure turbine 14 that is not supplied to the low-pressure turbine 16.

A condenser (not shown) is disposed around the high-pressure turbine 14 to condense the main steam that has passed through the high-pressure turbine 14 back into water. A recirculation pump (not shown) is disposed between the condenser (not shown) and the reactor 12 to return the water condensed from the main steam by the condenser (not shown) to the reactor 12.

The signal processing unit 50 has a turbine load setting unit 51, a deviation calculation unit 52, a regulator valve opening setting unit 53, an extraction valve opening setting unit 54, and an exhaust valve opening setting unit 55.

The turbine load setting unit 51 is a setting means for setting the load amount of the turbine based on the output target value A11.
The deviation calculation unit 52 is a calculation means that calculates the amount of deviation between the output target value A11 and the actual output value A12.
The regulating valve opening setting unit 53 is a setting means for setting the speed and magnitude of the opening of the steam regulating valve 40 .
The bleed valve opening setting unit 54 is a setting means for setting the speed and magnitude of the opening of the bleed valve 41 .
The exhaust valve opening setting unit 55 is a setting means for setting the speed and magnitude of the opening of the exhaust valve 42 .

The reactor power setting unit 60 also has a control rod withdrawal/insertion command unit 62 and a recirculation flow control unit 63.

The control rod withdrawal/insertion command unit 62 is a control means for controlling the reactor power by commanding a support means (not shown) for the control rods arranged inside the reactor 12 to withdraw or insert the control rods.
The recirculation flow rate control unit 63 is a control means for controlling the recirculation flow rate when the cooling water condensed from the main steam in a condenser (not shown) is returned to the reactor 12 .

The output target value A11 of the nuclear power plant 10 and the actual output value A12 of the generator 17 are input to the signal processing unit 50 from the outside. The output target value A11 is input to the turbine load setting unit 51 and the deviation calculation unit 52. The output target value A11 is also input to the deviation calculation unit 52.

The turbine load setting unit 51 sets the turbine load based on the output target value A11, and outputs a turbine load setting signal A13 representing the set turbine load to the regulating valve opening setting unit 53. The regulating valve opening setting unit 53 sets the speed and magnitude of the opening of the steam regulating valve 40 based on the turbine load setting signal A13, and outputs a regulating valve opening setting signal A14 representing the set speed and magnitude of the opening of the steam regulating valve 40 to the steam regulating valve 40. The drive means of the steam regulating valve 40 (regulating valve servo, not shown) adjusts the opening of the steam regulating valve 40 to the set speed and magnitude based on the regulating valve opening setting signal A14.

The deviation calculation unit 52 also calculates the deviation between the output target value A11 and the actual output value A12, and outputs a deviation signal A15 representing the calculated deviation to the extraction valve opening setting unit 54 and the exhaust valve opening setting unit 55.

The bleed valve opening setting unit 54 sets the speed and magnitude of the opening of the bleed valve 41 based on the deviation signal A15, and outputs an bleed valve opening setting signal A16 representing the set speed and magnitude of the opening of the bleed valve 41 to the bleed valve 41. The drive means for the bleed valve 41 (a bleed valve servo, not shown) adjusts the opening of the bleed valve 41 to the set speed and magnitude based on the bleed valve opening setting signal A16.

The exhaust valve opening setting unit 55 also sets the speed and magnitude of the opening of the exhaust valve 42 based on the deviation signal A15, and outputs an exhaust valve opening setting signal A17 representing the set speed and magnitude of the opening of the exhaust valve 42 to the exhaust valve 42. The drive means for the exhaust valve 42 (exhaust valve servo, not shown) adjusts the opening of the exhaust valve 42 to the set speed and magnitude based on the exhaust valve opening setting signal A17.

The reactor power setting unit 60 receives a reactor power signal A18 representing the reactor power from the reactor 12. The reactor power signal A18 is input to the control rod withdrawal/insertion command unit 62 and the recirculation flow control unit 63.

The control rod withdrawal/insertion command unit 62 sets the position of the control rod based on the reactor power signal A18, and outputs a control rod withdrawal/insertion command A19 to a support means (not shown) for the control rod, which instructs the control rod to move to the set position. Based on the control rod withdrawal/insertion command A19, the support means (not shown) moves the control rod to the set position, and commands the support means for the control rod arranged inside the reactor 12 to withdraw or insert the control rod, thereby controlling the reactor power.

The recirculation flow rate control unit 63 also sets the recirculation flow rate based on the reactor power signal A18, and outputs a recirculation flow rate control signal A20 representing the set recirculation flow rate to a recirculation pump (not shown). The recirculation pump (not shown) returns the cooling water condensed from the main steam in a condenser (not shown) to the reactor 12 based on the recirculation flow rate control signal A20. In this way, the power control device 11 maintains the water level inside the reactor 12 at the set water level.

In this way, the output control device 11 is used for a nuclear power plant 10 that includes a turbine (high-pressure turbine 14) driven by steam generated in the nuclear reactor 12, a generator 17 that is driven by the turbine to generate electricity, an extraction valve 41 that adjusts the flow rate of the extraction steam flowing out from the turbine, and an exhaust valve 42 installed in the exhaust system of the turbine. The output control device 11 also includes a signal processing unit 50 that controls the opening of the extraction valve and the exhaust valve based on the output target value A11 of the nuclear power plant and the actual output value A12 of the generator, and a reactor power setting unit 60 that sets the reactor power of the nuclear reactor.

When the load on the high-pressure turbine 14 (turbine) is increased, the signal processing unit 50 temporarily increases the load increase on the high-pressure turbine 14 by narrowing the opening of the extraction valve 41 and the exhaust valve 42, and while the load increase is being temporarily increased, the reactor power setting unit 60 controls the reactor power to increase.

When the load on the high-pressure turbine 14 (turbine) is increased, this type of output control device 11 narrows the opening of the extraction valve 41 and the exhaust valve 42 to temporarily increase the amount of load increase and to increase the reactor output while the amount of load increase is being temporarily increased. This allows the output control device 11 to maintain the generator output at an increased level even after the load is increased.

When the load on the high-pressure turbine 14 (turbine) is reduced, the signal processing unit 50 temporarily increases the amount of load reduction on the high-pressure turbine 14 by widening the opening of the extraction valve 41 and the exhaust valve 42, and while the amount of load reduction is temporarily increased, the reactor power setting unit 60 performs control to reduce the reactor power.

When the load on the high-pressure turbine 14 (turbine) is reduced, this type of output control device 11 increases the opening of the extraction valve 41 and the exhaust valve 42 to temporarily increase the amount of load reduction and reduce the reactor output while the amount of load reduction is being temporarily increased. This allows the output control device 11 to maintain the generator output at a reduced level even after the load is reduced.

The operation of the output control device 11 will be described below with reference to Figures 1 and 2. Here, the operation when the load on the high-pressure turbine 14 (turbine) is increased will be mainly described, and the operation when the load on the high-pressure turbine 14 (turbine) is decreased will not be described (this also applies to other embodiments). In addition, the operation of the output control device 11 when a signal is sent from the deviation calculation unit 52 to the extraction valve opening setting unit 54 and the exhaust valve opening setting unit 55 will be mainly described.

As shown in FIG. 1, the output target value A11 of the nuclear power plant 10 and the actual output value A12 of the generator 17 are input from the outside to the signal processing unit 50 of the output control device 11. The output target value A11 and the actual output value A12 are then input to the deviation calculation unit 52.

The deviation calculation unit 52 calculates the deviation between the output target value A11 and the actual output value A12, and outputs a deviation signal A15 representing the calculated deviation to the extraction valve opening setting unit 54 and the exhaust valve opening setting unit 55.

The bleed valve opening setting unit 54 sets the speed and magnitude of the opening of the bleed valve 41 based on the deviation signal A15, and outputs the bleed valve opening setting signal A16 representing the set speed and magnitude of the opening of the bleed valve 41 to the bleed valve 41. Here, the bleed valve opening setting signal A16 output at this time is described as having contents that instruct the drive means of the bleed valve 41 (bleed valve servo, not shown) to operate as shown in the bleed amount change graph B11 shown in FIG. 2. The bleed amount change graph B11 represents the change in the bleed amount. In the example shown in FIG. 2, the bleed amount change graph B11 is set to reduce the bleed amount, which is initially a rated value, from time a to time b based on the deviation signal A15. The drive means of the bleed valve 41 (bleed valve servo, not shown) adjusts the opening of the bleed valve 41 to the set speed and magnitude based on the bleed valve opening setting signal A16.

The exhaust valve opening setting unit 55 sets the speed and magnitude of the opening of the exhaust valve 42 based on the deviation signal A15, and outputs an exhaust valve opening setting signal A17 representing the set speed and magnitude of the opening of the exhaust valve 42 to the exhaust valve 42. Here, the exhaust valve opening setting signal A17 output at this time is described as having contents that instruct the driving means of the exhaust valve 42 (exhaust valve servo, not shown) to operate as shown in the exhaust volume change graph B12 shown in FIG. 2. The exhaust volume change graph B12 represents the change in the exhaust volume. In the example shown in FIG. 2, the exhaust volume change graph B12 is configured to reduce the extraction volume, which is initially the rated value, from time c to time d based on the deviation signal A15. The driving means of the exhaust valve 42 (exhaust valve servo, not shown) adjusts the opening of the exhaust valve 42 to the set speed and magnitude based on the exhaust valve opening setting signal A17.

The control valve opening setting unit 53 also sets the speed and magnitude of the opening of the steam control valve 40 based on the turbine load setting signal A13, and outputs a control valve opening setting signal A14 representing the set speed and magnitude of the opening of the steam control valve 40 to the steam control valve 40. The drive means of the steam control valve 40 (control valve servo, not shown) adjusts the opening of the steam control valve 40 to the set speed and magnitude based on the control valve opening setting signal A14.

The control rod withdrawal/insertion command unit 62 of the reactor power setting unit 60A sets the position of the control rod based on the reactor power signal A18, and outputs a control rod withdrawal/insertion command A19 to a support means (not shown) for the control rod, which instructs the control rod to move to the set position. Based on the control rod withdrawal/insertion command A19, the support means (not shown) moves the control rod to the set position, and commands the support means for the control rod arranged inside the reactor 12 to withdraw or insert the control rod, thereby controlling the reactor power.

The recirculation flow rate control unit 63 of the reactor power setting unit 60A sets the recirculation flow rate based on the reactor power signal A18, and outputs a recirculation flow rate control signal A20 representing the set recirculation flow rate to a recirculation pump (not shown). The recirculation pump (not shown) returns the cooling water condensed from the main steam in a condenser (not shown) to the reactor 12 based on the recirculation flow rate control signal A20. In this way, the power control device 11 maintains the water level inside the reactor 12 at the set water level.

The drive means for the bleed valve 41 (bleed valve servo, not shown) adjusts the opening of the bleed valve 41, and the drive means for the exhaust valve 42 (exhaust valve servo, not shown) adjusts the opening of the exhaust valve 42, so that the actual output value of the generator 17 changes as shown by the solid line in the output change graph B14 in FIG. 2. The change in the actual output value of the generator 17 at this time is faster and larger than the change in the case of only throttling the bleed air, as shown by the dotted line in the output change graph B14.

In response to a request to change the generator output in a short period of time, this type of output control device 11 can temporarily increase the generator output by extracting and exhausting main steam, while increasing the reactor output while ensuring the integrity of the fuel rods. This can improve the load following performance of the nuclear power plant 10.

The times a, b, c, and d can be set based on the deviation signal A15 output from the deviation calculation unit 52. By performing this type of control, the output control device 11 can change the extraction air volume and the exhaust volume based on the deviation between the output target value A11 and the actual output value A12.

In addition, compared to power improvement by bleed throttling, power improvement by exhaust throttling has the advantage of having a peak operation that temporarily increases power. This is because it takes a certain amount of time for the exhaust pressure, which is the rate-limiting (i.e., controlling) factor for power increase during exhaust throttling, to reach a saturated value, and so the range of power increase expands until the exhaust pressure reaches a saturated value. Therefore, by controlling the nuclear power plant 10, as shown in the output change graph B14 in Figure 2, by combining the peak operation of the generator output by exhaust throttling and the generator output increase by bleed throttling, it is possible to temporarily improve load following performance and increase the amount of power increase after the exhaust pressure is saturated.

In this embodiment, the control operation of the output control device 11 when increasing the output has been described, but the output control device 11 can also perform a similar control operation when decreasing the output.

As described above, according to the output control device 11 of this embodiment 1, in response to a request to change the generator output in a short period of time, the generator output can be temporarily increased by extracting and exhausting the main steam, and during that time, the reactor output can be increased while ensuring the integrity of the fuel rods. This makes it possible to improve the load following performance of the nuclear power plant 10.

[Embodiment 2]
The improvement in generator output by throttling the bleed air and exhaust gas of the output control device 11 according to the first embodiment described above may only be possible for a certain period of time from the viewpoint of the soundness of the feed water heater 19 and the drain tank 21 to which the bleed air and exhaust gas are applied. Therefore, the improvement in generator output of the output control device 11 according to the first embodiment described above may be temporary.

Therefore, in this embodiment, an output control device 11A is provided that realizes control that improves the generator output by bleed and exhaust throttling, as well as the furnace output, so that the increased output can be maintained even after the generator output has increased.

The configuration of the output control device 11A according to the second embodiment will be described below with reference to Figs. 3 and 4. Fig. 3 is a schematic diagram of a nuclear power plant 10 equipped with the output control device 11A according to the second embodiment. Fig. 4 is a control block diagram of the extraction valve opening setting unit 54 and the exhaust valve opening setting unit 55 of the output control device 11A, and the reactor 12.

As shown in FIG. 3, the output control device 11A of this embodiment 2 differs from the output control device 11 of embodiment 1 (see FIG. 1) in that it has a signal processing unit 50A instead of the signal processing unit 50, and a reactor power setting unit 60A instead of the reactor power setting unit 60.

The signal processing unit 50A (see FIG. 3) is different from the signal processing unit 50 (see FIG. 1) in the following respects.
(1) A deviation calculation unit 56 is added that calculates the amount of deviation between the output target value A11 and the actual output value A12.
(2) A deviation signal A31 representing the deviation amount (hereinafter, sometimes referred to as the "first deviation amount") between the output target value A11 and the actual output value A12 calculated by the deviation calculation unit 56 is input to a turbine load deviation calculation unit 57 and a reactor power deviation calculation unit 61 described below.
(3) A turbine load deviation calculation unit 57 is added between the turbine load setting unit 51 and the regulating valve opening setting unit 53. The turbine load deviation calculation unit 57 calculates the deviation amount (hereinafter sometimes referred to as the “second deviation amount”) between the turbine load amount represented by the turbine load setting signal A13 and the first deviation amount represented by the deviation signal A31.
(4) The deviation signal A32 representing the second deviation amount calculated by the turbine load deviation calculation unit 57 is input to the regulator valve opening setting unit 53.

Moreover, the reactor power setting unit 60A (see FIG. 3) is different from the reactor power setting unit 60 (see FIG. 1) in the following points.
(1) A reactor power deviation calculation unit 61 is added to calculate the deviation amount between the reactor power signal A18 and the deviation signal A31 (hereinafter, sometimes referred to as the "third deviation amount").
(2) A deviation signal A33 indicating the third deviation amount calculated by the reactor power deviation calculation unit 61 is input to the control rod withdrawal/insertion command unit 62 and the recirculation flow rate control unit 63.

By the way, the change in generator output by increasing the reactor power output is slower than the change in generator output by bleed and exhaust throttling, but has the advantage that the output can be maintained even after the output is increased. In other words, the change in generator output by bleed and exhaust throttling is not easy to maintain the output after the output is increased, but it can realize a reactor power increase control with excellent output increase speed. On the other hand, the change in generator output by increasing the reactor power output is inferior in output increase speed, but it can realize a reactor power increase control with easy to maintain the output after the output is increased. The output control device 11A according to this embodiment 2 is configured to realize a control that combines the change in generator output by bleed and exhaust throttling and the change in generator output by increasing the reactor power output. Such an output control device 11A according to this embodiment 2 can perform output control of the nuclear power plant 10 with a fast output increase speed and maintaining the output after the output is increased.

The operation of the output control device 11A will be described below with reference to Figures 3 and 4. Here, the operation of the output control device 11A when sending a signal from the deviation calculation unit 52 to the extraction valve opening setting unit 54 and the exhaust valve opening setting unit 55 will be mainly described.

As shown in FIG. 3, the output target value A11 of the nuclear power plant 10 and the actual output value A12 of the generator 17 are input from the outside to the signal processing unit 50 of the output control device 11A. The output target value A11 and the actual output value A12 are then input to the deviation calculation unit 52 and the deviation calculation unit 56.

Similar to the output control device 11 according to the first embodiment, in the output control device 11A according to this embodiment, the deviation calculation unit 52 calculates the deviation between the output target value A11 and the actual output value A12, and outputs a deviation signal A15 representing the calculated deviation to the extraction valve opening setting unit 54 and the exhaust valve opening setting unit 55.

The bleed valve opening setting unit 54 sets the speed and magnitude of the opening of the bleed valve 41 based on the deviation signal A15, and outputs an bleed valve opening setting signal A16 representing the set speed and magnitude of the opening of the bleed valve 41 to the bleed valve 41. Here, the bleed valve opening setting signal A16 output at this time will be described as having contents that instruct the drive means of the bleed valve 41 (bleed valve servo, not shown) to operate as shown in the bleed volume change graph B11 shown in Figures 2 and 4. The drive means of the bleed valve 41 (bleed valve servo, not shown) adjusts the opening of the bleed valve 41 to the set speed and magnitude based on the bleed valve opening setting signal A16.

The exhaust valve opening setting unit 55 sets the speed and magnitude of the opening of the exhaust valve 42 based on the deviation signal A15, and outputs an exhaust valve opening setting signal A17 representing the set speed and magnitude of the opening of the exhaust valve 42 to the exhaust valve 42. Here, the exhaust valve opening setting signal A17 output at this time is described as having contents that instruct the drive means of the exhaust valve 42 (exhaust valve servo, not shown) to operate as shown in the exhaust volume change graph B12 shown in Figures 2 and 4. The drive means of the exhaust valve 42 (exhaust valve servo, not shown) adjusts the opening of the exhaust valve 42 to the set speed and magnitude based on the exhaust valve opening setting signal A17.

Meanwhile, unlike the output control device 11 according to embodiment 1, in the output control device 11A according to this embodiment, the deviation calculation unit 56 calculates the deviation amount (first deviation amount) between the output target value A11 and the actual output value A12, and outputs the deviation signal A31 representing the calculated first deviation amount to the turbine load deviation calculation unit 57 and the reactor power deviation calculation unit 61 of the reactor power setting unit 60A.

The turbine load deviation calculation unit 57 calculates the deviation amount (second deviation amount) between the turbine load setting signal A13 and the deviation signal A31 representing the first deviation amount, and outputs the deviation signal A32 representing the calculated second deviation amount to the regulator valve opening setting unit 53.

The control valve opening setting unit 53 sets the speed and magnitude of the opening of the steam control valve 40 based on the deviation signal A32 representing the second deviation amount, and outputs a control valve opening setting signal A14a representing the set speed and magnitude of the opening of the steam control valve 40 to the steam control valve 40. The drive means of the steam control valve 40 (control valve servo, not shown) adjusts the opening of the steam control valve 40 to the set speed and magnitude based on the control valve opening setting signal A14a.

In addition, the reactor power deviation calculation unit 61 of the reactor power setting unit 60A calculates the deviation amount (third deviation amount) between the reactor power signal A18 and the deviation signal A31 representing the first deviation amount, and outputs the deviation signal A33 representing the calculated third deviation amount to the control rod withdrawal/insertion command unit 62 and the recirculation flow rate control unit 63.

The control rod withdrawal/insertion command unit 62 sets the position of the control rod based on the deviation signal A33 representing the third deviation amount, and outputs a control rod withdrawal/insertion command A19a to a support means (not shown) for the control rod, which commands the control rod to move to the set position. The support means (not shown) moves the control rod to the set position based on the control rod withdrawal/insertion command A19a, and commands the support means for the control rod arranged inside the reactor 12 to withdraw or insert the control rod, thereby controlling the reactor power.

The recirculation flow rate control unit 63 also sets the recirculation flow rate based on the deviation signal A33 representing the third deviation amount, and outputs a recirculation flow rate control signal A20a representing the set recirculation flow rate to a recirculation pump (not shown). The recirculation pump (not shown) returns the cooling water condensed from the main steam in a condenser (not shown) to the reactor 12 based on the recirculation flow rate control signal A20a. As a result, the power control device 11A maintains the water level inside the reactor 12 at the set water level.

The power control device 11A can realize reactor power control that changes, for example, like the reactor power control pattern B13 shown in Figure 4, by controlling the adjustment of the opening of the steam control valve 40 using the control valve opening setting signal A14a, controlling the withdrawal or insertion of the control rod using the control rod withdrawal/insertion command A19a, and controlling the adjustment of the recirculation flow rate using the recirculation flow rate control signal A20a.

As a result, the output control device 11A can realize an actual output value of the generator 17 that changes as shown by the solid line in the output change graph B14a in FIG. 4. The change in the actual output value of the generator 17 at this time is faster and the amount of change is greater than the change in the case where only the bleed air is throttled, as shown by the dotted line in the output change graph B14a. Moreover, the actual output value realized by the output control device 11A of this embodiment 2 differs from the actual output value realized by the output control device 11 of the first embodiment (see the output change graph B14 in FIG. 2) in that it first rises to near the output target value A11, then drops, and then rises again to the output target value A11.

That is, the operation of the output control device 11A according to this embodiment is the same as that of the output control device 11 according to the first embodiment in terms of the operation of controlling the opening degree of the extraction valve and the exhaust valve. On the other hand, the operation of the output control device 11A according to this embodiment is different from that of the output control device 11 according to the first embodiment in terms of the operation of controlling the reactor power in that a deviation signal A31 representing a first deviation amount between the output target value A11 and the actual output value A12 is sent to the reactor power setting unit 60. The output control device 11A according to this embodiment changes (increases) the reactor power, for example, as in the reactor power control pattern B13 shown in FIG. 4. The time of increasing the reactor power is set to the same time as the time c when exhaust throttling is started. The output control device 11A increases the reactor power while temporary power increase control by exhaust throttling is being performed, as shown in the output change graph B14a shown in FIG. 4, thereby making it possible to achieve the target generator output more quickly.

In this embodiment, the control operation of the output control device 11A when increasing the output has been described, but the output control device 11A can also perform a similar control operation when decreasing the output.

As described above, the output control device 11A according to the second embodiment can improve the load following performance of the nuclear power plant 10, similar to the output control device 11 according to the first embodiment.

[Embodiment 3]
In the power control device 11A of embodiment 2, when the difference between the power target value A11 and the actual power value A12 becomes large and the reactor power is suddenly increased (changed), there is a possibility that the fuel rods in the core may be damaged due to a sudden change in temperature, and other problems may occur, so it is preferable to maintain the integrity of the fuel rods.

Therefore, in this embodiment, we provide a power control device 11B that can maintain the integrity of such fuel rods.

The configuration of the output control device 11B according to the third embodiment will be described below with reference to Figs. 5 and 6. Fig. 5 is a schematic diagram of a nuclear power plant 10 equipped with the output control device 11B according to the third embodiment. Fig. 6 is a control block diagram of the extraction valve opening setting unit 54, the exhaust valve opening setting unit 55, and the reactor 12 of the output control device 11B.

As shown in FIG. 5, the output control device 11B according to the third embodiment differs from the output control device 11A according to the second embodiment (see FIG. 3) in that it has a signal processing unit 50B instead of the signal processing unit 50A.

The signal processing unit 50B (see FIG. 5) is different from the signal processing unit 50A (see FIG. 3) in the following respects.
(1) A change rate limiting unit 59 is added between the deviation calculation unit 56 and the turbine load deviation calculation unit 57 and between the deviation calculation unit 56 and the reactor power deviation calculation unit 61 of the reactor power setting unit 60.
(2) A fuel rod integrity evaluation signal A99 representing an evaluation of the integrity of the fuel rod is input to the change rate limiting unit 59 from an externally disposed evaluation device 58.
(3) When there is a problem with the soundness of the fuel rod, the change rate limiting unit 59 outputs a deviation signal A31a, which places a limit on changes in reactor power, to the turbine load deviation calculation unit 57 and the reactor power deviation calculation unit 61 of the reactor power setting unit 60, instead of the deviation signal A31.
(4) The control rod withdrawal/insertion command unit 62 limits the control rod withdrawal/insertion speed, and the recirculation flow rate control unit 63 limits the recirculation flow rate.

The evaluation of whether or not there is a problem with the integrity of the fuel rods can be performed based on the maximum linear power density of the core fuel rods. Alternatively, the evaluation of whether or not there is a problem with the integrity of the fuel rods can be performed based on the burnup history of the fuel rods. Alternatively, the evaluation of whether or not there is a problem with the integrity of the fuel rods can be performed based on the minimum safe critical power ratio set for the reactor 12.

The operation of the output control device 11B will be described below with reference to Figures 5 and 6. Here, the operation of the output control device 11B when sending a signal from the deviation calculation unit 52 to the extraction valve opening setting unit 54 and the exhaust valve opening setting unit 55 will be mainly described.

As shown in FIG. 5, the output target value A11 of the nuclear power plant 10 and the actual output value A12 of the generator 17 are input from the outside to the signal processing unit 50 of the output control device 11B. Then, the output target value A11 and the actual output value A12 are input to the deviation calculation unit 52 and the deviation calculation unit 56.

As with the output control devices 11 and 11A according to the other embodiments, in the output control device 11B according to the present embodiment, the deviation calculation unit 52 calculates the deviation between the output target value A11 and the actual output value A12, and outputs a deviation signal A15 representing the calculated deviation to the bleed valve opening setting unit 54 and the exhaust valve opening setting unit 55. The operation of the bleed valve opening setting unit 54 and the exhaust valve opening setting unit 55 of the output control device 11B according to the present embodiment is the same as the operation of the bleed valve opening setting unit 54 and the exhaust valve opening setting unit 55 of the output control device 11 and 11A according to the other embodiments. In addition, the operation of the deviation calculation unit 56 of the output control device 11B according to the present embodiment is the same as the operation of the deviation calculation unit 56 of the output control device 11 and 11A according to the other embodiments.

However, unlike the output control devices 11 and 11A according to the other embodiments, in the output control device 11B according to this embodiment, a deviation signal A31 representing the first deviation amount calculated by the deviation calculation unit 56 is input to the change rate limiting unit 59. In addition, a fuel rod soundness evaluation signal A99 representing an evaluation of the soundness of the fuel rod is input to the change rate limiting unit 59 from an external evaluation device 58. The evaluation device 58 is a device that evaluates the soundness of the fuel rod.

The change rate limiting unit 59 determines whether or not there is a problem with the integrity of the fuel rod based on the fuel rod integrity evaluation signal A99. If there is a problem with the integrity of the fuel rod, the change rate limiting unit 59 outputs the deviation signal A31a to the turbine load deviation calculating unit 57 and the reactor power deviation calculating unit 61 of the reactor power setting unit 60, instead of the deviation signal A31 output from the deviation calculating unit 56.

The turbine load deviation calculation unit 57, to which the deviation signal A31a is input, calculates the deviation amount (second deviation amount) between the turbine load setting signal A13 and the deviation signal A31a, and outputs the deviation signal A32a representing the calculated second deviation amount to the regulator valve opening setting unit 53.

The control valve opening setting unit 53 sets the speed and magnitude of the opening of the steam control valve 40 based on the deviation signal A32a representing the second deviation amount, and outputs a control valve opening setting signal A14b representing the set speed and magnitude of the opening of the steam control valve 40 to the steam control valve 40. Unlike the control valve opening setting signal A14a (see FIG. 3) of the second embodiment, this control valve opening setting signal A14b includes content that limits the speed and magnitude of the opening of the steam control valve 40. The drive means of the steam control valve 40 (control valve servo, not shown) adjusts the opening of the steam control valve 40 to the set speed and magnitude based on the control valve opening setting signal A14b.

In addition, the reactor power deviation calculation unit 61 of the reactor power setting unit 60 calculates the deviation amount (third deviation amount) between the reactor power signal A18 and the deviation signal A31a representing the first deviation amount, and outputs the deviation signal A33a representing the calculated third deviation amount to the control rod withdrawal/insertion command unit 62 and the recirculation flow rate control unit 63.

The control rod withdrawal/insertion command unit 62 sets the position of the control rod based on the deviation signal A33a representing the third deviation amount, and outputs a control rod withdrawal/insertion command A19b to a support means (not shown) for the control rod, which commands the control rod to move to the set position. Unlike the control rod withdrawal/insertion command A19a (see FIG. 3) of the second embodiment, this control rod withdrawal/insertion command A19b includes content that limits the control rod withdrawal/insertion speed. Based on the control rod withdrawal/insertion command A19b, the support means (not shown) moves the control rod to a set position and commands the support means for the control rod arranged inside the reactor 12 to withdraw or insert the control rod, thereby controlling the reactor power.

The recirculation flow rate control unit 63 also sets the recirculation flow rate based on the deviation signal A33a representing the third deviation amount, and outputs a recirculation flow rate control signal A20b representing the set recirculation flow rate to a recirculation pump (not shown). Unlike the recirculation flow rate control signal A20a (see FIG. 3) of the second embodiment, this recirculation flow rate control signal A20b includes content that limits the recirculation flow rate. The recirculation pump (not shown) returns the cooling water condensed from the main steam in a condenser (not shown) to the reactor 12 based on the recirculation flow rate control signal A20b. As a result, the power control device 11B maintains the water level inside the reactor 12 at the set water level.

In this type of power control device 11B, the control rod withdrawal/insertion command unit 62 limits the control rod withdrawal/insertion speed. In addition, the reactor power deviation calculation unit 61 limits the recirculation flow rate (the flow rate of cooling water returned to the reactor 12).

The power control device 11B can realize reactor power control that changes, for example, like the reactor power control pattern B13b shown in FIG. 6, by controlling the adjustment of the opening of the steam control valve 40 using the control valve opening setting signal A14b, controlling the withdrawal or insertion of the control rod using the control rod withdrawal/insertion command A19b, and controlling the adjustment of the recirculation flow rate using the recirculation flow rate control signal A20b.

As a result, the output control device 11B can realize an actual output value of the generator 17 that changes as shown by the solid line in the output change graph B14b in FIG. 6. The actual output value realized by the output control device 11B of this embodiment 3 is different from the actual output value realized by the output control device 11A of embodiment 2 (see output change graph B14a in FIG. 4) in that a limit value AZ is set.

That is, the operation of the output control device 11B according to this embodiment is the same as the operation of the output control devices 11 and 11A according to the other embodiments in terms of the operation of the opening control of the extraction valve and the exhaust valve. On the other hand, the operation of the output control device 11B according to this embodiment is different from the operation of the output control device 11A according to the second embodiment in that a limit is set on the actual output value A12. Specifically, in the output control device 11B according to this embodiment, a deviation signal A31a representing a first deviation amount between the output target value A11 and the actual output value A12 is sent to the reactor power setting unit 60. In response to this, the output control device 11B changes (increases) the reactor power, for example, as shown in the reactor power control pattern B13b in FIG. 6. The time of increasing the reactor power is set to the same time as the time c at which the exhaust throttling starts. The output control device 11B compares the deviation signal A31 with the fuel rod soundness evaluation signal A99 in the rate of change limiting unit 59, and when the rate of the reactor power increase request exceeds the rate specified by the fuel rod soundness evaluation signal A99, the reactor power speed is set to a value equal to or lower than the value set in the rate of change limiting unit 59. As a result, the output control device 11B according to this embodiment is capable of load following operation within a range not exceeding the limit value AZ of the soundness of the fuel rods during the load following operation of the nuclear power plant 10, as shown in the output change graph B14b in FIG. 6. The deviation output signal is compared with the fuel rod soundness evaluation signal A99 from the evaluation device 58 that evaluates the soundness of the fuel rods in the rate of change limiting unit 59, and when the rate of the reactor power increase request exceeds the signal from the rate of change limiting unit 59, the reactor power speed is set to a value equal to or lower than the value set in the rate of change limiting unit. As shown in the output change graph B14b due to the control of this nuclear power plant, load following of the nuclear power plant is possible within a range that does not exceed the limit value AZ for the integrity of the fuel rods.

The limit value AZ is a limit value for ensuring the integrity of the fuel rods during load following operation of the nuclear power plant 10. The limit value AZ is set based on the maximum linear power density of the core fuel rods, the burnup history of the fuel rods, the safe minimum limit power ratio set for the reactor 12, and the like. The limit value AZ may be included in the fuel rod integrity evaluation signal A99. Alternatively, the limit value AZ may be set by the change rate limiting unit 59 based on the fuel rod integrity evaluation signal A99.

As described above, the output control device 11B according to this embodiment 3 can improve the load following performance of the nuclear power plant 10, similar to the output control devices 11 and 11A according to the other embodiments.

[Embodiment 4]
In this embodiment, an output control device 11C is provided that stores in a storage unit the actual rates at the time of turbine load change operations previously performed in the nuclear power plant 10, and utilizes the actual rates.

The configuration of the output control device 11C according to the fourth embodiment will be described below with reference to FIG. 7. FIG. 7 is a schematic diagram of a nuclear power plant 10 equipped with the output control device 11C according to the fourth embodiment.

As shown in FIG. 7, the output control device 11C of this embodiment 4 differs from the output control device 11 of embodiment 1 (see FIG. 1) in that it has an actual rate memory unit 71.

The actual rate memory unit 71 is a memory unit that stores actual rates during turbine load change operations previously performed in the nuclear power plant 10. The actual rate memory unit 71 stores a load increase actual rate A71a during turbine load increase operations previously performed in the nuclear power plant 10 and a load reduction actual rate A71b during turbine load reduction operations. The actual rate memory unit 71 may be arranged outside the output control device 11C.

The load increase actual rate A71a and the load decrease actual rate A71b are output from the actual rate memory unit 71 to the turbine load setting unit 51 during operation of the nuclear power plant 10.

When increasing the turbine load, the turbine load setting unit 51 sets the current turbine load to be lower than the load increase actual rate A71a recorded in the actual rate memory unit 71.

In addition, when the turbine load is reduced, the turbine load setting unit 51 sets the current turbine load to be higher than the load reduction actual rate A71b recorded in the actual rate memory unit 71.

According to the output control device 11C of this fourth embodiment, like the output control devices 11, 11A, and 11B of the other embodiments, the load following performance of the nuclear power plant 10 can be improved.
Moreover, according to the output control device 11C, the nuclear power plant 10 can be controlled so that, when the turbine load is increased, the current turbine load is lower than the load increase actual rate A71a recorded in the past, and, when the turbine load is decreased, the nuclear power plant 10 can be controlled so that the current turbine load is higher than the load decrease actual rate A71b recorded in the past.

The present invention is not limited to the above-described embodiment, but includes various modified examples. For example, the above-described embodiment has been described in detail to explain the present invention in an easy-to-understand manner, and is not necessarily limited to having all of the configurations described. In addition, it is possible to replace part of the configuration of the embodiment with another configuration, and it is also possible to add another configuration to the configuration of the embodiment. In addition, it is possible to add, delete, or replace part of each configuration with another configuration.

10 Nuclear power plant 11, 11A, 11B Output control device 12 Nuclear reactor 13 Control rod 14 High pressure turbine (turbine)
15 Steam/water separator 16 Low pressure turbine 17 Generator 18 Low pressure feed water heater 19 Feed water heater 20 High pressure feed water heater 21 Drain tank 31, 32, 33, 34, 35, 36, 37, 38 Piping 39 Piping (exhaust system)
40 Steam control valve (control valve)
Description of the Reference Signs 41 Bleed valve 42 Exhaust valve 50, 50A, 50B Signal processing unit 51 Turbine load setting unit 52 Deviation calculation unit 53 Regulating valve opening setting unit 54 Bleed valve opening setting unit 55 Exhaust valve opening setting unit 56 Deviation calculation unit 57 Turbine load deviation calculation unit 58 Evaluation device 59 Change rate limiting unit 60, 60A Reactor power setting unit 61 Reactor power deviation calculation unit 62 Control rod withdrawal/insertion command unit 63 Recirculation flow rate control unit 71 Actual rate storage unit (storage unit)
A11 Output target value A12 Actual output value A13 Turbine load setting signal A14, A14a Regulating valve opening setting signal A15 Deviation signal A16 Extraction valve opening setting signal A17 Exhaust valve opening setting signal A18 Furnace output signal (furnace output)
A19, A19a, A19b Control rod withdrawal/insertion command (position)
A20, A20a, A20b Recirculation flow control signal (recirculation flow rate)
A31, A31a Deviation signal (first deviation amount)
A32, A32a: deviation signal (second deviation amount)
A33, A33a Deviation signal (third deviation amount)
A71a Load increase actual rate A71b Load decrease actual rate A99 Fuel rod integrity evaluation signal (fuel rod integrity evaluation)
AZ limit value B11 Extraction amount change graph B12 Exhaust amount change graph B13, B13b Reactor power control pattern B14, B14a, B14b Power change graph

Claims (12)

a signal processing unit for controlling openings of the extraction valve and the exhaust valve based on an output target value of the nuclear power plant and an actual output value of the generator, for a nuclear power plant including a turbine driven by steam generated in a nuclear reactor, a generator driven by the turbine to generate electric power, an extraction valve for adjusting a flow rate of the extraction steam flowing out from the turbine, and an exhaust valve provided in an exhaust system of the turbine;
A reactor power setting unit that sets the reactor power of the reactor,
2. An output control device for a nuclear power plant, comprising: a signal processing unit that, when a load is increased on the turbine, reduces openings of the extraction valve and the exhaust valve to temporarily increase an amount of load increase on the turbine; and, while the amount of load increase is being temporarily increased, the reactor power setting unit performs control to increase the reactor power. 2. The output control device for a nuclear power plant according to claim 1,
2. An output control device for a nuclear power plant, comprising: a signal processing unit that, when a load on the turbine is reduced, increases an amount of load reduction on the turbine temporarily by increasing an opening degree of the extraction valve and the exhaust valve; and, while the amount of load reduction is temporarily increased, the reactor power setting unit performs control to reduce the reactor power. 2. The output control device for a nuclear power plant according to claim 1,
The signal processing unit includes:
a turbine load setting unit that sets a load amount of the turbine based on the output target value;
a regulator valve opening setting unit that sets an opening of a regulator valve that controls an amount of main steam supplied to the turbine based on a load amount of the turbine set by the turbine load setting unit;
a deviation calculation unit that calculates a deviation amount between the output target value and the actual output value;
an air bleed valve opening setting unit that sets an opening of the air bleed valve based on the deviation amount calculated by the deviation calculation unit;
an exhaust valve opening setting unit that sets an opening of the exhaust valve based on the deviation amount calculated by the deviation calculation unit. 4. The output control device for a nuclear power plant according to claim 3,
the signal processing unit has a turbine load deviation calculation unit, between the turbine load setting unit and the regulating valve opening setting unit, which calculates a first deviation amount between the output target value and the actual output value, and a second deviation amount between the load amount of the turbine set by the turbine load setting unit and the first deviation amount,
4. An output control device for a nuclear power plant, wherein the control valve opening setting unit sets the opening of the control valve based on the second deviation amount. 2. The output control device for a nuclear power plant according to claim 1,
The reactor power setting unit includes:
a control rod withdrawal/insertion command unit that controls reactor power by commanding a support means for a control rod disposed inside the reactor to withdraw or insert the control rod;
a recirculation flow rate control unit for controlling a recirculation flow rate when water condensed from the main steam in a condenser is returned to the reactor,
The control rod withdrawal/insertion command unit sets the position of the control rod based on the reactor power of the reactor, and
2. A power control device for a nuclear power plant, wherein the recirculation flow rate control unit sets the recirculation flow rate based on a reactor power of the nuclear reactor. 6. The output control device for a nuclear power plant according to claim 5,
the reactor power setting unit has a reactor power deviation calculation unit that calculates a first deviation amount between the power target value and the actual power value, and a third deviation amount between the reactor power of the reactor and the first deviation amount,
The control rod withdrawal/insertion command unit sets a position of the control rod based on the third deviation amount, and
4. An output control device for a nuclear power plant, wherein the recirculation flow rate control unit sets the recirculation flow rate based on the third deviation amount. 6. The output control device for a nuclear power plant according to claim 5,
An output control device for a nuclear power plant, characterized in that when there is a problem with the integrity of the fuel rod evaluated by the evaluation device, the control rod withdrawal/insertion command unit limits the control rod withdrawal/insertion speed, and the recirculation flow rate control unit limits the recirculation flow rate. 8. The output control device for a nuclear power plant according to claim 7,
13. A power control device for a nuclear power plant, wherein the evaluation of whether or not there is a problem with the soundness of the fuel rods is performed based on the maximum linear heat generation density. 8. The output control device for a nuclear power plant according to claim 7,
13. A power control device for a nuclear power plant, wherein the evaluation of whether or not there is a problem with the soundness of the fuel rods is performed based on a burnup history. 8. The output control device for a nuclear power plant according to claim 7,
1. A power control device for a nuclear power plant, wherein the evaluation of whether or not there is a problem with the soundness of the fuel rods is performed based on a minimum safe critical power ratio. 4. The output control device for a nuclear power plant according to claim 3,
a recording unit that records an actual load increase rate during a load increase operation of the turbine and an actual load reduction rate during a load reduction operation of the turbine that have been previously performed in the nuclear power plant,
The turbine load setting unit is
When the load of the turbine is increased, a current load amount of the turbine is set to be lower than the load increase actual rate recorded in the recorder,
1. An output control device for a nuclear power plant, comprising: a control unit for controlling a load on the turbine, the control unit controlling the load on the turbine being increased by a current ... 1. A method for controlling output of a nuclear power plant comprising: a turbine driven by steam generated in a nuclear reactor; a generator driven by the turbine to generate electric power; an extraction valve for adjusting the flow rate of extraction steam flowing out from the turbine; and an exhaust valve provided in an exhaust system of the turbine, the method comprising the steps of: when a load is increased on the turbine, narrowing the openings of the extraction valve and the exhaust valve to temporarily increase the amount of load increase on the turbine, and performing control to increase the reactor output of the nuclear reactor while the amount of load increase is temporarily increased; and when a load is decreased on the turbine, widening the openings of the extraction valve and the exhaust valve to temporarily increase the amount of load decrease on the turbine, and performing control to decrease the reactor output of the nuclear reactor while the amount of load decrease is temporarily increased.

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