TWI813086B - Power generation system and its control method and program - Google Patents

Abstract

[Problem] The purpose is to provide a power generation system that can increase the output of a generator, and its control method and program. [Solution] A power generation system including: a boiler, a steam turbine that rotates using steam generated by the boiler, a generator that generates electricity through the rotation of the steam turbine, and a system control device (15) that controls the boiler; system control device (15) Equipped with: a correction value setting part (20), which, when the load state is above the threshold value and the load variation range is within a prescribed range, determines based on the deviation between the generator required output (MWD) and the generator output ( ΔMW) to calculate a correction value; and a boiler control unit (40) that increases the generator required output (MWD) based on the correction value and generates a command for controlling the boiler, which is a boiler input command (BID).

Description

Power generation system and its control method and program

This disclosure relates to a power generation system and its control method and program.

In thermal power plants, etc., power generation systems with boilers and steam turbines as main components are often used. The power generation system uses the steam generated in the boiler to generate electricity through a steam turbine. [Prior technical literature] [Patent Document]

[Patent Document 1] Japanese Patent Publication No. 11-182212 [Patent Document 2] Japanese Patent Publication No. 2018-185600

[Problem to be solved by the invention]

For example, in summer, phenomena such as a decrease in the vacuum pressure of the condenser occur as the outside air temperature rises. In such a case, the generator output is likely to decrease (for example, Patent Document 1), and the output corresponding to the rated load may not be obtained. In addition, there is a possibility that the output may decrease due to long-term deterioration of the device (for example, Patent Document 2). If the generator output is insufficient in this way, sufficient power generation may not be obtained and the power generation may be insufficient.

This disclosure was created in view of such a situation, and its purpose is to provide a power generation system, a control method and a program thereof, which can increase the output of the generator. [Means to solve the problem]

A first aspect of the present disclosure is a power generation system including: a boiler; a steam turbine that is rotated using steam generated by the boiler; a generator that generates electricity by the rotation of the steam turbine; and a system control device that controls the boiler. ; Among them, the aforementioned system control device includes: a correction value setting unit that calculates the correction based on the deviation between the generator required output and the generator output when the load state is above the threshold and the load variation range is within a prescribed range. value; and a boiler control unit that increases the required output of the generator based on the correction value and generates an instruction for controlling the boiler, that is, a boiler input instruction.

A second aspect of the present disclosure is a method of controlling a power generation system including a boiler, a steam turbine that is rotated using steam generated by the boiler, and a generator that generates electricity by rotating the steam turbine; wherein , the control method includes: when the load state is above the threshold and the load change amplitude is within the specified range, a correction value is calculated based on the deviation between the generator's required output and the generator's output; and based on the aforementioned correction value A program that increases the required output of the generator and generates instructions for controlling the boiler is a boiler input instruction.

A third aspect of the present disclosure is a control program for a power generation system that includes a boiler, a steam turbine that is rotated using steam generated by the boiler, and a generator that generates electricity by rotating the steam turbine; wherein , this control program is used to cause the computer to perform the following processing: when the load state is above the threshold and the load change range is within the specified range, the correction value is calculated based on the deviation between the generator's required output and the generator's output. ; and the processing of increasing the required output of the generator based on the correction value and generating an instruction for controlling the boiler, that is, a boiler input instruction. [Effects of the invention]

According to this disclosure, the effect of increasing the generator output can be exerted.

Hereinafter, a power generation system and a control method thereof according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram schematically showing the overall structure of the power generation system 1 according to this embodiment. In FIG. 1 , a power generation system 1 includes a boiler 10 , a steam turbine 3 that is rotated using steam generated by the boiler 10 , a generator 5 that generates electricity by rotating the steam turbine 3 , and a system control that controls the steam turbine 3 . Device 15. In addition, the boiler 10 is not limited to CFB, but other types of boilers such as HRSG can also be applied. The boiler 10 is provided with a combustion furnace 2 for burning fuel. The steam generated in the water-cooled wall 2' provided in the combustion furnace 2 is supplied to the steam turbine 3 through the steam pipe L1. In the steam pipe L1, a primary superheater 4a, a desuperheater 16, and a secondary superheater 4b are provided in series. Although FIG. 1 shows a case where there is one desuperheater 16, it may also be provided at the rear stage of the secondary superheater 4b.

The steam pipe L1 between the boiler 10 and the steam turbine 3 is provided with a steam regulating valve 6 for adjusting the amount of steam supplied to the steam turbine 3 . When the full voltage conversion operation mode is adopted, the steam regulating valve 6 can be maintained in the fully open state regardless of the generator required output (power generation required output) MWD.

The power generation system 1 is provided with: a water supply pump 8 that supplies water to the water wall 2' provided in the combustion furnace 2, a condenser 9 that recovers steam discharged from the steam turbine 3 and returns it to water (liquid), and a condenser 9 that generates The water is led to the pipe L2 of the water supply pump 8 and so on.

Furthermore, a pressure sensor 11 for measuring the main steam pressure is provided between the secondary superheater 4b and the steam regulating valve 6 in the steam pipe L1. The measured value of the pressure sensor 11 is output to the system control device 15 and used for control of the steam turbine 3 .

In the power generation system 1 having such a configuration, fuel is burned in the combustion furnace 2, and the water supply pump 8 is started to flow water to the water wall 2' provided in the combustion furnace 2, thereby generating steam. The steam generated in the water-cooled wall 2' of the combustion furnace 2 is led to the primary superheater 4a to be overheated, then cooled in the desuperheater 16, and then overheated in the secondary superheater 4b. The steam reheated in the secondary superheater 4b is introduced into the steam turbine 3 and used to drive the steam turbine 3. The generator 5 generates electricity through the rotation of the steam turbine 3, and the generated electric power is sent to, for example, an electric power system (not shown).

The steam that drives the steam turbine 3 is led to the condenser 9 and is returned to (liquid) via the condenser 9 . The water generated in the condenser 9 returns to the water supply pump 8 again through various devices (not shown) provided in the pipe L2 and is used again in the boiler 10 .

The system control device 15 controls the boiler 10 and the like.

FIG. 2 is a diagram illustrating an example of the hardware configuration of the system control device 15 according to this embodiment. As shown in FIG. 2 , the system control device 15 is a computer system (computer system) and includes, for example, a CPU 110 and a ROM (Read Only Memory) 120 for storing programs executed by the CPU 110 and functions as a workpiece area when each program is executed. RAM (Random Access Memory) 130, a hard disk device (HDD) 140 as a large-capacity storage device, and a communication unit 150 for connecting to a network or the like. Furthermore, as a large-capacity memory device, a solid-state drive (SSD) can also be used. These various units are connected through bus bars 180 .

Furthermore, the system control device 15 may include an input unit composed of a key disk, a mouse, etc., a display unit composed of a liquid crystal display device that displays data, and the like.

In addition, the storage medium for storing programs and the like executed by the CPU 110 is not limited to the ROM 120 . For example, it may also be a magnetic disk, an opto-magnetic disk, a semiconductor memory, or other auxiliary memory devices.

A series of processing procedures for realizing various functions described below are recorded in the hard disk device 140 and the like in the form of a program. The CPU 110 reads the program into the RAM 130 and the like to perform information processing and calculation processing. Through this, the processes described below are realized. various functions. Moreover, the program can also be applied in a form that is pre-installed in ROM 120 or other memory media, or in a form that provides a state of memory in a computer-readable memory medium, or in a form that is generated through wired or wireless The type of delivery by means of communication, etc. The so-called computer-readable memory media include magnetic discs, opto-magnetic discs, CD-ROMs, DVD-ROMs, semiconductor memories, etc.

FIG. 3 is a diagram showing the schematic configuration of the system control device 15 . As shown in FIG. 3 , the system control device 15 includes a correction value setting unit 20 , a main steam pressure setting unit 30 , a boiler control unit 40 , and a regulation control unit 50 .

The correction value setting unit 20 calculates the correction value AM1 based on the deviation between the generator required output MWD and the generator output when the load state is equal to or higher than the threshold value and the load variation range is within a predetermined range. Specifically, the correction value setting unit 20 includes a subtraction unit 21, a condition determination unit 22, a signal switching unit 23, a passivation processing unit 24, a PI control unit 25, a change rate limiting unit 26, a holding unit 27, and a signal switching unit 28. .

The subtraction unit 21 calculates the deviation (difference) between the generator required output MWD and the actual output (generator output), and outputs the difference to the PI control unit 25 . In the following description, the deviation is expressed as ΔMW. The deviation (ΔMW) is the value obtained by subtracting the actual output from the generator required output MWD.

The condition determination unit 22 performs condition determination and outputs whether the condition is satisfied or the condition is not satisfied. As shown in FIG. 3 , for example, in the condition determination unit 22, the first condition, the second condition, and the third condition (logical product) are set. Furthermore, only the first condition and the second condition may be included, or other conditions may be added. The condition determination unit 22 outputs the condition is satisfied when all the set conditions are satisfied, and outputs the condition is not satisfied when even one condition is not satisfied.

The first condition is that the load state is above the threshold. The threshold is set based on the rated load. Specifically, the threshold value is set near the rated load (for example, a value lower than a predetermined margin from the rated load). That is, the first condition is to determine that the load state is close to the rated load. Regarding the load status, the generator can be used to request the output MWD. That is, the first condition may be that the generator required output MWD is equal to or higher than the preset threshold β. In this way, it is determined that the rated load state is (or close to it) under the first condition.

The second condition is that the load change amplitude (load change amount per specified time) is within the specified range. The specified range is set in advance as a range that is regarded as a constant state in which there is no change in the load. That is, ideally, it is determined that the load has not changed (the load is not changing) under the second condition. The so-called load is not changing, for example, may be determined based on the absence of a load increase (change) request signal. The load increase request signal is transmitted through instructions from the central power supply command post. When the required load of the power plant (generator required output MWD) rises, it is sent remotely or manually by the operator until it reaches the target load (generator). the input signal until output). In this way, it can be determined that the load has not changed (the load change amplitude is within the specified range) without the load increase request signal.

The third condition is that the opening degree of the steam regulating valve 6 is equal to or higher than the threshold value α. Specifically, the third condition is that the opening degree of the steam regulating valve 6 is fully open. For this reason, the threshold α can be set in advance to a value that can determine that the steam regulating valve 6 is fully open. Furthermore, the threshold α can also be set with an additional predetermined margin relative to the fully open state.

In this way, the condition determination unit 22 uses the first condition, the second condition, and the third condition as AND conditions, and determines that all conditions are satisfied.

Furthermore, the condition determination unit 22 may determine, as an additional condition (the fourth condition), that the outside air temperature is a predetermined value or above, and that the deviation between the generator required output MWD and the generator output is a predetermined value or above. At least any one of the situations.

For example, when the outside air temperature is high in summer, the generator output is likely to be insufficient due to a drop in the vacuum pressure of the condenser 9 or the like. That is, by determining that the outside air temperature is equal to or higher than a predetermined value, it is possible to determine the possibility of insufficient output as the outside air temperature rises. The threshold is preset through the relationship between the outside air temperature and the generator output deficiency.

Furthermore, by determining that the deviation between the generator required output MWD and the generator output is more than a predetermined value, it is possible to determine the output shortage in summer. The determined value is set based on, for example, the allowable value of the deviation between the generator required output MWD and the generator output. In addition, the phenomenon of insufficient generator output may also occur due to factors that have nothing to do with the outside air temperature, such as the deterioration of the machine. Therefore, by determining that the deviation between the generator required output MWD and the generator output is greater than or equal to a predetermined value, it is possible to determine a deficiency in the generator output that is not based on the cause.

That is, ideally, the condition determination unit 22 uses the first condition, the second condition, the third condition, and the fourth condition as AND conditions, and determines that all conditions are satisfied.

The signal switching unit 23 outputs either one of the selection port B1 and the selection port B2 to the output port C1 based on the input from the input port A1. Specifically, when a signal indicating that the condition is satisfied is input to the input port A1, the input to the selection port B1 is output to the output port C1. On the other hand, when a signal indicating that the condition is not satisfied is input to the input port A1, the input to the selection port B2 is output to the output port C1. That is, when the condition determination unit 22 determines that the condition is established, ΔMW is output, and when the condition determination unit 22 determines that the condition is not established, the signal generated by the signal generator (zero signal) is output.

The passivation processing unit 24 performs passivation processing on the signal from the signal switching unit 23 . Specifically, the passivation processing unit 24 performs a change suppression process to suppress a time change in the deviation between the generator's required output MWD and the actual output, that is, ΔMW. The change suppression processing is performed via a moving average in a specific aspect. That is, ΔMW is leveled. The passivation process is also performed when a zero signal is input from the signal switching unit 23. However, since the zero signal does not change with time, the input is output as it is.

In this manner, the correction value setting unit 20 performs a change suppression process for suppressing a time change in ΔMW and calculates the correction value AM1 described later. Therefore, rapid time changes in the calculated correction value AM1 are suppressed. That is, the time change of the correction value AM1 becomes gentle, and the sudden generator output is suppressed.

The PI control unit 25 performs PI control based on the signal (that is, ΔMW) output from the passivation processing unit 24 and outputs a control value. In the PI control unit 25, the lower limit value and the upper limit value are set. For example, the lower limit value is 0 and the upper limit value is a (>0). In this way, the control value is limited to the upper and lower limits, and the range of the output value can be limited.

The change rate limiting unit 26 performs processing to suppress temporal changes in the control signal output from the PI control unit 25 . In this way, rapid time changes in the relevant control signals are suppressed.

The holding unit 27 maintains the value of the signal output from the change rate limiting unit 26 when it reaches the actual MW target value. The so-called actual MW target value is the rated output of the plant. That is, the actual MW target value is the maximum value of the output correction value AM1.

The signal switching unit 28 outputs either one of the selection port E1 and the selection port E2 to the output port F1 based on the input of the input port D1. Specifically, when a signal indicating that the condition is satisfied is input to the input port D1, the input to the selection port E1 is output to the output port F1. On the other hand, when a signal indicating that the condition is not satisfied is input to the input port D1, the input to the selection port E2 is output to the output port F1. That is, when the condition determination unit 22 determines that the condition is established, the signal input from the holding unit 27 is output, and when the condition determination unit 22 determines that the condition is not established, the signal (zero signal) generated by the signal generator is output.

In this way, the correction value AM1 is calculated based on ΔMW. The correction value AM1 is based on ΔMW. The larger the ΔMW is, that is, the smaller the actual output is compared to the generator required output MWD, the larger the value is. The calculated correction value AM1 is output to the main steam pressure setting unit 30 . Furthermore, when the condition is not satisfied and a zero signal is output from the signal switching unit 28, the correction value AM1 is zero, so it will not affect the subsequent stage.

The main steam pressure setting unit 30 sets the main steam pressure command CM2 based on the generator request output MWD and the correction value AM1. For this purpose, the main steam pressure setting unit 30 includes a function unit 31 and an adding unit 32 .

The function unit 31 converts the generator required output MWD to the main steam pressure command (before correction) CM1. That is, the function unit 31 performs conversion based on the relationship between the generator required output MWD and the main steam pressure command CM1 that is preset based on the specifications of the power generation system 1 .

The adder unit 32 adds the correction value AM1 set in the correction value setting unit 20 to the main steam pressure command CM1 output from the function unit 31, thereby correcting the main steam pressure command CM1 and outputs the main steam pressure command ( After correction) CM2. In this way, correction is performed in the direction in which the main steam pressure command increases.

In this way, the main steam pressure setting unit 30 generates the main steam pressure command CM2. The generated main steam pressure command CM2 is output to the boiler control unit 40 .

The boiler control unit 40 generates a boiler input demand (BID) which is a command for controlling the boiler 10 . As will be described later, the boiler control unit 40 performs a process of increasing the generator required output MWD based on the correction value AM1 by using the main steam pressure command CM2 that reflects the correction value AM1. Specifically, the boiler control unit 40 increases the generator required output MWD according to the deviation between the main steam pressure command CM2 and the main steam pressure, and generates the boiler input command BID.

For this purpose, the boiler control unit 40 includes a subtraction unit 41, a PI control unit 42, an addition unit 43, and a function unit 44.

The subtraction unit 41 calculates the deviation (difference) between the main steam pressure command CM2 and the main steam pressure (actual value), and outputs it to the PI control unit 42 . The deviation is a value obtained by subtracting the main steam pressure from the main steam pressure command CM2.

The PI control unit 42 performs PI control based on the signal output from the subtraction unit 41 (that is, the deviation between the main steam pressure command CM2 and the main steam pressure) and outputs a control value. This control value becomes the correction value AM2 required for the generator output MWD based on the correction value AM1 output from the correction value setting unit 20 .

The correction value AM2 for the generator required output MWD is based on the deviation between the main steam pressure command CM2 and the main steam pressure, and becomes a value that becomes larger as the main steam pressure decreases relative to the main steam pressure command CM2. In other words, the main steam pressure command CM2 is calculated based on the correction value AM1 generated in the correction value setting unit 20. Therefore, the correction value AM2 for the generator required output MWD is larger as ΔMW, that is, the larger the generator required output MWD is, that is, the larger the generator required output MWD is. MWD, the smaller the actual output, the larger the value.

The adder unit 43 adds the generator required output MWD to the control value output from the PI control unit 42 (correction value AM2 for the generator required output MWD), thereby correcting the generator required output MWD. The generator's required output MWD is added to the correction value AM2, so the generator's required output MWD is corrected in the increasing direction.

The function unit 44 converts the corrected generator required output MWD output from the adding unit 43 into a boiler input command BID and outputs it. The boiler input command BID is used to generate, for example, a fuel flow command in the combustion furnace 2 or a water supply flow command in the water wall 2'. Figure 3 shows a situation used in the control of a payment conveyor. When the boiler input command BID increases, the fuel flow rate command in the combustion furnace 2 or the water supply flow rate command to the water wall 2' also increases. As a result, the main steam pressure increases. That is, the generator output increases.

The boiler input command BID is not limited to the above-mentioned fuel flow command in the combustion furnace 2 as long as it is a parameter that can increase the main steam pressure to increase the generator output.

The regulation control unit 50 controls the opening degree of the steam regulating valve (regulator) 6 . Specifically, the subtraction unit 51 calculates the deviation between the generator required output MWD and the generator output, and the PI control unit 52 converts the difference into a control signal. The control signal is used to control the opening degree of the steam regulating valve 6, thereby controlling the opening degree of the regulator so that the deviation between the generator required output MWD and the generator output is zero.

Next, one example of the processing performed by the system control device 15 will be described with reference to FIG. 4 . FIG. 4 is a flowchart showing an example of the steps of the boiler input command output processing according to the present embodiment. The flow shown in FIG. 4 is executed repeatedly in a predetermined control cycle, for example. In the flow of FIG. 4 , the case where all of the first condition, the second condition, the third condition, and the fourth condition are used is explained. However, the same process is also performed when the number of conditions is different.

First, it is determined whether the first condition is satisfied (S101). If the first condition is not satisfied ("No" determination in S101), the process proceeds to S106.

When the first condition is satisfied (YES determination in S101), it is determined whether the second condition is satisfied (S102). If the second condition is not satisfied ("No" determination in S102), the process proceeds to S106.

When the second condition is satisfied (YES determination in S102), it is determined whether the third condition is satisfied (S103). If the third condition is not satisfied ("No" determination in S103), the process proceeds to S106.

When the third condition is satisfied (YES determination in S103), it is determined whether the fourth condition is satisfied (S104). If the fourth condition is not satisfied ("No" determination in S104), the process proceeds to S106.

When the fourth condition is satisfied (YES determination in S104), the correction value AM1 is calculated based on the deviation between the generator required output MWD and the generator output (S105).

On the other hand, when at least any one of the first condition, the second condition, the third condition, and the fourth condition is not satisfied, the correction value AM1 is zero (S106).

Next, the main steam pressure command CM2 is set based on the generator required output MWD and the correction value AM1 (S107). When the correction value AM1 is zero, the main steam pressure command CM2 is set based only on the generator request output MWD.

Next, the correction value AM2 for the generator required output MWD is calculated based on the deviation between the main steam pressure command CM2 and the main steam pressure (S108).

Next, after correcting the generator required output MWD using the correction value AM2, the boiler input command BID is output (S109).

In this way, especially when the load state is close to the rated load and there is no load fluctuation (the opening degree of the steam regulating valve 6 is fully open), when the generator output is insufficient, the correction value is used to make the boiler input command BID move toward Because of the correction in the increasing direction, the output can be increased to make up for the insufficient output.

Next, the effect of the processing performed by the above-mentioned system control device 15 will be described with reference to FIG. 5 . Figure 5 shows the main steam pressure on the vertical axis (left axis), the opening degree of the steam adjustment valve on the vertical axis (right axis), and the main steam flow rate on the horizontal axis, indicating A mode and B mode respectively. In mode A, the steam regulating valve 6 is fully open and constant. In B mode, the steam regulating valve 6 is variable.

When the generator required output MWD becomes high and reaches the point M, it is difficult to increase the generator output because the steam regulating valve 6 is fully open. Therefore, in the area above the point M, which is the variable pressure operation area, a correction value is calculated to increase the boiler input command BID as in this embodiment. In this way, the main steam pressure can be increased and the generator output can be increased. In this variable pressure operation range, the turbine is under generator output control (the opening degree of the steam regulating valve 6 is constant), and the boiler 10 is under main steam pressure control (corrected via ΔMW).

In this way, the generator output can be increased by correcting it to increase the boiler input command BID according to ΔMW.

As described above, in the power generation system 1 that uses the boiler 10 or the steam turbine 3 to generate electricity, by using the power generation system, its control method, and the program according to this embodiment, in the high load state where the load state is above the threshold value, and When the load change amplitude is within the specified range and there is no (less) load change, the correction value is calculated based on the generator required output and the generator output. Next, the generator required output MWD is increased via the correction value to generate the boiler input command BID. For this reason, when the load state is above the threshold and the load change amplitude is within the specified range, the boiler input command BID can be increased. Through this, the generator output can be increased.

In particular, considering that when the load state is above the threshold and the load change amplitude is within the specified range, an increase in the generator output is usually unnecessary. However, even if it is due to any reason (such as environmental changes or machine deterioration, etc.) ) and in the event of a shortage in generator output, the shortage can also be covered.

Furthermore, by making a correction value based on the generator required output and the generator output, the difference between the generator required output and the generator output can be reduced. The boiler input command BID is generated based on the deviation between the main steam pressure command CM2 and the main steam pressure set through the generator required output MWD and the correction value, thereby generating the boiler input command BID so that the correction value is taken into account while The difference between the main steam pressure command CM2 and the main steam pressure is suppressed.

When the outside air temperature is above a specified value, or when the deviation between the generator's required output MWD and the generator output is above a specified value, the output can be increased. For example, when the outside air temperature is high in summer, the output is likely to be insufficient due to a drop in the vacuum pressure of the condenser 9 or the like. For this reason, the output is increased by a correction value to cover the deficiency.

The present disclosure is not limited to the above-described embodiments, and various modifications can be made without departing from the gist of the invention.

For example, in the above embodiment, when a load increase request is input, the amount of fuel input to the combustion furnace 2 and the amount of water supply to the water wall 2' are increased. However, compared with the amount of fuel in the combustion furnace 2, Responsiveness, the responsiveness of water supply is faster on this side. Therefore, if the fuel flow rate command and the water supply flow rate command are increased at the same time, first, the amount of water supplied to the water wall 2' increases, and then the temperature in the combustion furnace 2 also starts to gradually rise. For this reason, the superheat degree at the outlet of the water-cooled wall 2' may decrease due to the amount of water supplied to the water-cooled wall 2'. In order to avoid such a situation, part of the water supply can be supplied to the desuperheater 16 provided on the steam outlet side of the primary superheater 4a bypassing the water wall 2', and sprayed as a spray. In this case, in the cooler 16, the spray amount increases. In this way, part of the water supplied to the water wall 2' is bypassed to the desuperheater 16, thereby preventing the above-mentioned decrease in the superheat degree at the outlet of the water wall 2'. Furthermore, when a desuperheater 16 is further provided on the steam outlet side of the secondary superheater 4b, the spray amount of each desuperheater 16 can also be increased.

The power generation system described in each embodiment described above, its control method and program are as follows. A power generation system (1) according to the present disclosure includes a boiler (10), a steam turbine (3) that is rotated using steam generated by the boiler, a generator that generates electricity by the rotation of the steam turbine, and a generator that controls the boiler. System control device (15); the aforementioned system control device is provided with: a correction value setting part (20), which, when the load state is above the threshold value and the load variation range is within a prescribed range, sets the output (MWD) according to the generator request. ) and the generator output to calculate a correction value; and a boiler control unit (40), which increases the required output of the generator based on the correction value and generates an instruction for controlling the boiler, that is, a boiler input instruction (BID) ).

According to the power generation system of the present disclosure, in a power generation system that uses a boiler or a steam turbine to generate electricity, there is no load change (less) when the load state is a high load state above a threshold and the load change amplitude is within a prescribed range. In this case, the correction value is calculated based on the generator required output and the generator output. Next, the generator required output is increased via the correction value to generate a boiler input command. For this reason, when the load state is above the threshold and the load change amplitude is within the specified range, the boiler input command can be increased. Through this, the generator output can be increased.

In particular, considering that when the load state is above the threshold and the load change amplitude is within the specified range, an increase in the generator output is usually unnecessary. However, even if it is due to any reason (such as environmental changes or machine deterioration, etc.) ) and in the event of a shortage in generator output, the shortage can also be covered.

Furthermore, by making a correction value based on the generator required output and the generator output, the difference between the generator required output and the generator output can be reduced.

The power generation system of the present disclosure may further include: a main steam pressure setting part (30), which sets the main steam pressure command according to the generator required output and the correction value; the boiler control part sets the main steam pressure command according to the main steam pressure. The deviation between the command and the main steam pressure increases the required output of the aforementioned generator and generates the aforementioned boiler input command.

According to the power generation system of the present disclosure, the boiler input command is generated based on the deviation between the main steam pressure command and the main steam pressure set through the generator required output and the correction value, thereby generating the boiler input command, so that while considering The correction value suppresses the difference between the main steam pressure command and the main steam pressure.

The power generation system related to the present disclosure may further include: a steam regulating valve (6), which is provided in the steam pipe connecting the aforementioned boiler and the aforementioned steam turbine; and the aforementioned correction value setting part is configured to adjust the load variation range when the load state is above a threshold value. Within the predetermined range, and when the opening degree of the steam regulating valve is equal to or higher than the threshold value, the correction value is calculated.

According to the power generation system of the present disclosure, even when the opening degree of the steam regulating valve is above the threshold and it is difficult to adjust the output due to the steam regulating valve, the boiler input command can be increased to increase the output.

In the power generation system according to the present disclosure, the correction value setting unit may be configured to operate at least one of a case where the outside air temperature is a predetermined value or more and a case where a deviation between the generator required output and the generator output is a predetermined value or more. In the case of square, calculate the aforementioned correction value.

According to the power generation system of the present disclosure, when the outside air temperature is equal to or higher than a predetermined value, or when the deviation between the required output of the generator and the output of the generator is equal to or greater than the predetermined value, the output can be increased. For example, when the outside air temperature is high in summer, the output is likely to be insufficient due to a drop in the vacuum pressure of the condenser (9). For this reason, the output is increased by a correction value to cover the deficiency.

In the power generation system according to the present disclosure, the correction value setting unit may perform a change suppression process for suppressing a time change in the deviation between the generator required output and the generator output, and calculate the correction value.

According to the power generation system of the present disclosure, since the time change of the deviation between the generator required output and the generator output is suppressed, the time change of the correction value also becomes gentle, and the sudden generator output is suppressed.

In the power generation system according to the present disclosure, the correction value setting unit may perform the variation suppression process through a moving average.

According to the power generation system of the present disclosure, time variation can be effectively suppressed through the moving average.

The control method related to the present disclosure is a control method of a power generation system including: a boiler, a steam turbine that is rotated using steam generated by the boiler, and a generator that generates electricity through the rotation of the steam turbine; wherein, This control method includes: a procedure for calculating a correction value based on the deviation between the generator's required output and the generator's output when the load state is above a threshold and the load change amplitude is within a specified range; and a program that uses the aforementioned correction value to The aforementioned generator requires an increase in output and generates instructions for controlling the aforementioned boiler, which is a program of boiler input instructions.

The control program related to the present disclosure is a control program for a power generation system that includes a boiler, a steam turbine that rotates using steam generated by the boiler, and a generator that generates electricity through the rotation of the steam turbine; wherein, This control program causes the computer to perform the following processing: when the load state is above the threshold and the load change range is within the specified range, the correction value is calculated based on the deviation between the generator's required output and the generator's output; and based on The aforementioned correction value is used to increase the required output of the aforementioned generator and generate instructions for controlling the aforementioned boiler, which is the process of boiler input instructions.

1: Power generation system 2: Combustion furnace 2':Water wall 3: Steam turbine 4a: Primary superheater 4b: Secondary superheater 5:Generator 6:Steam adjustment valve 8:Water supply pump 9:Condenser 10: Boiler 11: Pressure sensor 15: System control device 16: Cooler 20: Correction value setting part 21:Subtraction operation part 22:Condition judgment department 23: Signal switching part 24: Passivation treatment department 25:PI Control Department 26:Change rate limit part 27:Maintenance Department 28: Signal switching part 30: Main steam pressure setting part 31: Function Department 32: Addition operation part 40: Boiler control department 41:Subtraction operation part 42:PI Control Department 43: Addition operation part 44: Function Department 50: Adjustment control department 51:Subtraction operation part 52:PI Control Department 110:CPU 120:ROM 130:RAM 140:Hard disk device 150:Communication Department 180:Bus A1:Input port AM1: Correction value AM2: Correction value B1: Select port B2: Select port BID: boiler input command C1: Output port CM1: Main steam pressure command CM2: Main steam pressure command D1: input port E1: Select port E2: Select port F1: Output port L1: Steam piping L2:Piping MWD: generator required output

[Fig. 1] is a block diagram schematically showing the overall structure of a power generation system according to an embodiment of the present disclosure. FIG. 2 is a diagram showing an example of the hardware configuration of a system control device according to an embodiment of the present disclosure. [Fig. 3] is a diagram showing the schematic configuration of a system control device according to an embodiment of the present disclosure. 4 is a flowchart showing an example of processing performed by the system control device according to one embodiment of the present disclosure. FIG. 5 is a diagram illustrating the effect of processing by the system control device according to one embodiment of the present disclosure.

15: System control device

20: Correction value setting part

21:Subtraction operation part

22:Condition judgment department

23: Signal switching part

24: Passivation treatment department

25:PI Control Department

26:Change rate limit part

27:Maintenance Department

28: Signal switching part

30: Main steam pressure setting part

31: Function Department

32: Addition operation part

40: Boiler control department

41:Subtraction operation part

42:PI Control Department

43: Addition operation part

44: Function Department

50: Adjustment control department

51:Subtraction operation part

52:PI Control Department

A1:Input port

AM1: Correction value

AM2: Correction value

B1: Select port

B2: Select port

BID: boiler input command

C1: Output port

CM1: Main steam pressure command

CM2: Main steam pressure command

D1: input port

E1,E2: Select port

F1: Output port

MWD: generator required output

△MW: deviation

Claims (8)

A power generation system including: a boiler; a steam turbine that is rotated using steam generated by the boiler; a generator that generates electricity through the rotation of the steam turbine; and a system control device that controls the boiler; wherein the system control device includes : The correction value setting part, which calculates the correction value based on the deviation between the generator required output and the generator output when the load state is above the threshold and the load variation range is within the specified range; and the boiler control part, which The required output of the generator is increased based on the correction value, and a command for controlling the boiler, that is, a boiler input command is generated. The power generation system of claim 1, wherein the power generation system is provided with: a main steam pressure setting unit that sets the main steam pressure command based on the generator required output and the aforementioned correction value; the aforementioned boiler control unit sets the main steam pressure command based on the aforementioned main steam pressure The deviation between the command and the main steam pressure increases the required output of the aforementioned generator and generates the aforementioned boiler input command. The power generation system of claim 1 or 2, wherein the power generation system is provided with: a steam regulating valve, which is provided in the steam piping connecting the aforementioned boiler and the aforementioned steam turbine; The correction value setting unit calculates the correction value when the load state is above a threshold value, the load change range is within a predetermined range, and the opening degree of the steam regulating valve is above the threshold value. The power generation system of claim 1 or 2, wherein the correction value setting unit is configured to operate at least one of a situation where the outside air temperature is a predetermined value or more, and a deviation between the generator required output and the generator output is a predetermined value or more. In the case of any one of them, the aforementioned correction value is calculated. The power generation system of claim 1 or 2, wherein the correction value setting unit performs a change suppression process to suppress a time change in the deviation between the generator required output and the generator output, and calculates the correction value. The power generation system according to claim 5, wherein the correction value setting unit performs the variation suppression process through a moving average. A control method for a power generation system provided with: a boiler, a steam turbine that is rotated using steam generated by the boiler, and a generator that generates electricity through the rotation of the steam turbine; wherein the control method includes: When the status is above the threshold and the load change amplitude is within the specified range, a procedure is used to calculate a correction value based on the deviation between the generator's required output and the generator's output; and to increase the aforementioned generator's required output based on the aforementioned correction value, Generating instructions for controlling the aforementioned boiler is also a program for boiler input instructions. A control program for a power generation system that includes a boiler, a steam turbine that is rotated using steam generated by the boiler, and a generator that generates electricity through the rotation of the steam turbine; wherein the control program is used to cause a computer to Execute the following processing: when the load state is above the threshold and the load change amplitude is within the specified range, the correction value is calculated based on the deviation between the generator required output and the generator output; and the aforementioned correction value is used to make the aforementioned The generator requires an increase in output and generates an instruction for controlling the aforementioned boiler, which is the processing of the boiler input instruction.

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