A control method and system for stack-following machine mode

Abstract

The present invention provides a control method and system for a reactor-following mode, belonging to the field of nuclear power plant control technology. The method comprises: determining an air intake control valve opening signal based on the difference between a first opening signal and a second opening signal to control the opening of the steam turbine's air intake control valve; determining a feedwater control valve opening signal based on the sum of a third opening signal and a fourth opening signal to control the opening of the steam generator's feedwater control valve; and determining a control rod actuation signal based on the sum of a first action signal and a second action signal to control the reactor's control rods. Compared to the traditional reactor-following control mode, the present invention adds a nonlinear deadband control link for the steam turbine, a feedwater feedforward control link, and a proportional differential control link for the reactor, ultimately achieving coordinated control objectives that take into account load power tracking performance, steam generator liquid level fluctuations, and the response speed of feedwater control and reactor power control.

Description

Technical Field

[0001] The present invention relates to the field of nuclear power plant control technology, and in particular to a control method and system for a reactor-following mode. Background Art

[0002] At present, most pressurized water reactor devices in nuclear power plants adopt the "machine-follows-reactor" or "reactor-follows-machine" control method, which basically means that the reactor, steam generator, and steam turbine operate relatively independently.

[0003] The existing control method cannot achieve coordinated control of the reactor-steam generator-steam turbine, and cannot meet the basic requirements of "quickly adapting to load power changes while keeping the steam generator liquid level and coolant average temperature within the allowable range". It has problems such as poor load power tracking performance, large fluctuations in steam generator liquid level and coolant average temperature, and long dynamic response process time. Summary of the Invention

[0004] The present invention provides a control method and system for a stack-following mode, which are used to solve the problems in the prior art of poor load power tracking performance, large fluctuations in the steam generator liquid level and the average coolant temperature, and long dynamic response process time.

[0005] In a first aspect, the present invention provides a control method for a stack-following mode, comprising: determining an air intake regulating valve opening signal based on a difference between a first opening signal and a second opening signal to control the opening of the air intake regulating valve of the steam turbine; the first opening signal is determined based on the power difference between the external load power and the actual power of the steam turbine, and the second opening signal is determined based on the fluctuation of the liquid level difference between the preset liquid level and the actual liquid level of the steam generator; and determining a feed water regulating valve opening signal based on the sum of the third opening signal and the fourth opening signal to control the opening of the feed water regulating valve of the steam generator. control; the third opening signal is determined based on the liquid level difference, feed water flow and steam flow of the steam generator, and the fourth opening signal is determined based on the power difference of the turbine; and, based on the sum of the first action signal and the second action signal, a control rod action signal is determined to achieve control of the control rods of the reactor; the first action signal is determined based on the coolant average temperature difference, reactor power and steam flow, and the second action signal is determined based on the external load power of the turbine; the coolant average temperature difference is the difference between the coolant average temperature set value and the coolant average temperature.

[0006] According to a control method for a stack-following mode provided by the present invention, a first opening signal is determined according to the power difference between the external load power and the actual generated power of the steam turbine, including: determining the first opening signal with the power difference of the steam turbine being zero as the target, so as to control the opening of the air intake regulating valve; and determining the second opening signal according to the fluctuation of the liquid level difference between the preset liquid level and the actual liquid level of the steam generator, including: when the absolute value of the liquid level difference is less than or equal to the preset dead zone limit value, generating a second opening signal that has no regulating effect on the opening of the air intake regulating valve; when the absolute value of the liquid level difference is greater than the preset dead zone limit value, generating a second opening signal whose size is positively correlated with the size of the absolute value.

[0007] According to a control method for a stack-following mode provided by the present invention, a third opening signal is determined based on the liquid level difference, feed water flow rate and steam flow rate of the steam generator, including: determining an expected feed water flow rate for compensating for the liquid level fluctuation of the steam generator based on the liquid level difference of the steam generator; determining the third opening signal based on the expected feed water flow rate, the feed water flow rate and the steam flow rate, and controlling the opening of the feed water regulating valve to achieve the supply of the expected feed water flow rate; and determining a fourth opening signal based on the power difference of the steam turbine, including: utilizing a proportional-integral control strategy to determine the fourth opening signal based on the power difference to control the opening of the feed water regulating valve to achieve regulation of the feed water flow rate.

[0008] According to a control method for a stack follower mode provided by the present invention, the method also includes: determining a water supply pump speed signal based on a pressure difference error of a water supply regulating valve, and adjusting the speed of the water supply pump so that the pressure difference error is less than a preset threshold; the pressure difference error is the difference between a front-to-rear pressure difference setting value and an actual measured value of the front-to-rear pressure difference of the water supply regulating valve.

[0009] According to a control method for a reactor-following mode provided by the present invention, a first action signal is determined based on the average coolant temperature difference, the reactor power and the steam flow rate, including: determining the required power of the reactor based on the sum of the output after proportional-integral control of the average coolant temperature difference and the steam flow rate; generating a first action signal based on the difference between the required power and the reactor power to achieve control of the control rods; and determining a second action signal based on the external load power of the turbine, including: utilizing a proportional-differential strategy to determine the second action signal based on the external load power to achieve control of the control rods.

[0010] According to a control method for a stack-following mode provided by the present invention, the formula for obtaining the coolant average temperature setting value is:

[0011]

[0012] Among them, F s Indicates the value of steam flow, Tavf Indicates the average coolant temperature setting value, F s1 F is the critical point for dividing high and low working conditions. s Less than F s1 It belongs to low working condition, which is greater than or equal to F s1 When it is high working condition, T1 represents the coolant average temperature setting value corresponding to the steam flow rate of zero, and T2 represents the steam flow rate of F s1 The corresponding average coolant temperature setting value.

[0013] According to a control method for a stack-following mode provided by the present invention, the average coolant temperature is the arithmetic average of the coolant hot end temperature and the coolant cold end temperature.

[0014] In a second aspect, the present invention further provides a control system for a stacker-following mode, comprising: a first control module, a second control module, and a third control module.

[0015] a first control module, configured to determine an air intake regulating valve opening signal based on a difference between a first opening signal and a second opening signal, so as to control the opening of the air intake regulating valve of the steam turbine; wherein the first opening signal is determined based on a power difference between an external load power and an actual generated power of the steam turbine, and the second opening signal is determined based on fluctuations in a liquid level difference between a preset liquid level and an actual measured liquid level of the steam generator; and

[0016] a second control module, configured to determine a feedwater regulating valve opening signal based on a sum of a third opening signal and a fourth opening signal, so as to control the opening of the feedwater regulating valve of the steam generator; the third opening signal being determined based on a liquid level difference, a feedwater flow rate, and a steam flow rate of the steam generator, and the fourth opening signal being determined based on a power difference of the steam turbine; and

[0017] The third control module is used to determine the control rod action signal based on the sum of the first action signal and the second action signal to achieve control of the control rods of the reactor; the first action signal is determined based on the coolant average temperature difference, reactor power and steam flow, and the second action signal is determined based on the external load power of the turbine; the coolant average temperature difference is the difference between the coolant average temperature set value and the coolant average temperature.

[0018] According to the present invention, a control system for a stacker-following machine mode further includes: a first calculation module;

[0019] The first calculation module is used to calculate the coolant average temperature setting value using the calculation formula of the coolant average temperature setting value; the calculation formula is specifically:

[0020]

[0021] Among them, F s Indicates the value of steam flow, T avf Indicates the average coolant temperature setting value, F s1 F is the critical point for dividing high and low working conditions. s Less than F s1 It belongs to low working condition, which is greater than or equal to F s1 When it is high working condition, T1 represents the coolant average temperature setting value corresponding to the steam flow rate of zero, and T2 represents the steam flow rate of F s1 The corresponding average coolant temperature setting value.

[0022] A control system for a stack-following mode provided by the present invention further includes: a second calculation module; the second calculation module is used to determine the average coolant temperature based on the arithmetic mean of the coolant hot end temperature and the coolant cold end temperature.

[0023] In a third aspect, the present invention provides an electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the control method for the stacking machine mode as described above are implemented.

[0024] In a fourth aspect, the present invention further provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of any of the above-described control methods for the stack-following mode.

[0025] The control method and system for the reactor-following mode provided by the present invention add a nonlinear dead zone control link of the steam turbine, a feedwater feedforward control link, and a proportional differential control link of the reactor, ultimately achieving the coordinated control goals of taking into account the three aspects of load power tracking performance, steam generator liquid level fluctuation, and feedwater control and reactor power control response speed. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the present invention or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0027] Figure 1 This is a principle framework diagram of the control method of the stack-following mode provided by the present invention;

[0028] Figure 2 It is a principle diagram of the nonlinear dead zone control link of the steam turbine provided by the present invention;

[0029] Figure 3This is a schematic diagram of the three-impulse cascade-feedforward composite control method for the water supply controller provided by the present invention;

[0030] Figure 4 This is a schematic diagram of the reactor power control method provided by the present invention;

[0031] Figure 5 This is a schematic diagram of a coolant average temperature setting calculation module provided by the present invention;

[0032] Figure 6 It is a structural schematic diagram of the electronic device provided by the present invention. DETAILED DESCRIPTION

[0033] To make the objectives, technical solutions, and advantages of the present invention more clear, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0034] It should be noted that, in the description of the embodiments of the present invention, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or also includes elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0035] The terms "first," "second," and the like in this application are used to distinguish similar objects, and are not used to describe a particular order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, so that the embodiments of this application can be implemented in orders other than those illustrated or described herein. Furthermore, the objects distinguished by "first," "second," and the like generally refer to a class of objects and do not limit the number of objects. For example, the first object may be one or more.

[0036] In order to more clearly illustrate the technical solution of the present invention, before specifically introducing the technical solution of the present invention, the actual application scenarios of the present invention and the technical requirements analysis process are further explained below.

[0037] In the control systems of the reactor, steam generator, and steam turbine in a nuclear power plant's pressurized water reactor (PWR) unit, the consistency between the turbine's actual output power and the load power reflects the energy supply-demand balance between the turbine and the external load. The stability of the steam generator liquid level and average coolant temperature reflects the energy supply-demand balance between the reactor, steam generator, and turbine. The dynamic characteristics of the reactor, steam generator, and turbine differ significantly: the turbine responds quickly to load power, while the reactor and steam generator respond more slowly due to their large thermal inertia. Therefore, the two energy supply-demand balances within and outside the PWR unit of a nuclear power plant are mutually constrained, creating an irreconcilable contradiction between the fast response to external load power and the stability of internal operating parameters.

[0038] The dynamic characteristics of rapid operating conditions in a nuclear power plant's pressurized water reactor (PWR) unit, including the reactor, steam generator, and steam turbine, indicate that there is significant inertial delay throughout the entire process, from control rod movement to reactor power changes, feedwater pump and feedwater regulating valve operation to compensate for steam generator liquid level fluctuations, to turbine inlet regulating valve operation to cause turbine output power changes. Relying solely on reactor power control and steam generator feedwater control will inevitably hinder rapid load power response.

[0039] Therefore, in order to improve the overall response performance of the pressurized water reactor device of the nuclear power plant, the heat storage capacity of the steam generator can be fully utilized under the premise of ensuring that the average coolant temperature and the steam generator liquid level fluctuation are within the allowable range. That is, when the load power changes, the average coolant temperature and the steam generator liquid level are allowed to fluctuate to a certain extent through the appropriate action of the turbine steam inlet regulating valve, and the initial load power response speed of the turbine is accelerated by releasing or absorbing part of the stored energy; at the same time, according to the external load power instruction, the power control of the reactor and the feed water control of the steam generator are strengthened, that is, the stored energy is restored so that the steam output of the steam generator is consistent with the load power of the turbine.

[0040] To address the problems of poor load power tracking performance and long dynamic response time in the "machine-following reactor" or "reactor-following machine" control mode of a nuclear power plant pressurized water reactor, the present invention provides a control method and system for the reactor-following-machine mode, which is used for the coordinated control of the reactor, steam generator, and steam turbine of a nuclear power plant pressurized water reactor. The specific control method includes:

[0041] (1) An air intake regulating valve opening signal is determined based on a difference between a first opening signal and a second opening signal to control the opening of the air intake regulating valve of the steam turbine. The first opening signal is determined based on a power difference between an external load power and an actual power generated by the steam turbine, and the second opening signal is determined based on fluctuations in a liquid level difference between a preset liquid level and an actual liquid level of the steam generator.

[0042] (2) Determining a feedwater regulating valve opening signal based on the sum of the third opening signal and the fourth opening signal to control the opening of the feedwater regulating valve of the steam generator. The third opening signal is determined based on the liquid level difference, feedwater flow rate, and steam flow rate of the steam generator, and the fourth opening signal is determined based on the power difference of the steam turbine.

[0043] (3) Determining a control rod actuation signal based on the sum of the first actuation signal and the second actuation signal to achieve control of the control rods of the reactor. The first actuation signal is determined based on the coolant average temperature difference, reactor power, and steam flow rate, and the second actuation signal is determined based on the external load power of the steam turbine; the coolant average temperature difference is the difference between the coolant average temperature set value and the coolant average temperature.

[0044] The control system designed based on the above control method specifically includes:

[0045] a first control module, configured to determine an air intake regulating valve opening signal based on a difference between a first opening signal and a second opening signal, so as to control the opening of the air intake regulating valve of the steam turbine; wherein the first opening signal is determined based on a power difference between an external load power and an actual generated power of the steam turbine, and the second opening signal is determined based on fluctuations in a liquid level difference between a preset liquid level and an actual measured liquid level of the steam generator; and

[0046] a second control module, configured to determine a feedwater regulating valve opening signal based on a sum of a third opening signal and a fourth opening signal, so as to control the opening of the feedwater regulating valve of the steam generator; the third opening signal being determined based on a liquid level difference, a feedwater flow rate, and a steam flow rate of the steam generator, and the fourth opening signal being determined based on a power difference of the steam turbine; and

[0047] The third control module is used to determine the control rod action signal based on the sum of the first action signal and the second action signal to achieve control of the control rods of the reactor; the first action signal is determined based on the coolant average temperature difference, reactor power and steam flow, and the second action signal is determined based on the external load power of the turbine; the coolant average temperature difference is the difference between the coolant average temperature set value and the coolant average temperature.

[0048] The following combination Figures 1-6 The control method and system for the stacker-follower mode provided by the above embodiment of the present invention are further described. In addition, in order to more concisely and clearly describe the technical solution of the present invention, the present invention focuses on describing the control system designed based on the control method provided by the present invention.

[0049] Figure 1This is a principle framework diagram of the control method of the stack-following mode provided by the present invention, such as Figure 1 As shown, based on the control method provided by the present invention, the designed reactor-steam generator-steam turbine coordinated control system includes: a reactor power controller (reactor power controller), a feedwater controller, a turbine controller, a nonlinear deadband control link, a feedforward control link, a proportional differential control link, a coolant average temperature setting calculation module (first calculation module), a coolant average temperature calculation module (second calculation module), and a control object. The control object includes: a reactor, a steam generator, a steam turbine, a feedwater pump, an air intake regulating valve, and a feedwater regulating valve. The implementation of the control system is described below.

[0050] Among them, the turbine controller is used to determine the first opening signal according to the power difference between the external load power and the actual power of the turbine, including: determining the first opening signal with the power difference of the turbine being zero as the goal to control the opening of the air intake regulating valve.

[0051] Specifically, the turbine controller uses the same control method as a conventional "stack-follower" system. It receives a power difference signal between the external load power and the actual turbine power. Using PID control or model predictive control strategies, it online calculates a first opening signal generated by the turbine controller for controlling the air intake control valve. By varying the opening of the air intake control valve, steam flow is regulated to align the actual turbine power with the external load power. When the external load power exceeds the actual turbine power, the air intake control valve is opened. When the external load power is less than the actual turbine power, the air intake control valve is closed.

[0052] Among them, the nonlinear dead zone control link is used to determine the second opening signal according to the fluctuation of the liquid level difference between the preset liquid level and the actual liquid level of the steam generator, including: when the absolute value of the liquid level difference is less than or equal to the preset dead zone limit value, generating a second opening signal that has no regulating effect on the opening of the air intake regulating valve; when the absolute value of the liquid level difference is greater than the preset dead zone limit value, generating a second opening signal whose size is positively correlated with the size of the absolute value.

[0053] Specifically, the nonlinear dead zone control link of the steam turbine is set to deal with the excessive rate and amplitude of load power growth, which leads to excessive fluctuation amplitude of the steam generator liquid level. Figure 2 As shown, Figure 2 It is a principle diagram of the nonlinear dead zone control link of the steam turbine provided by the present invention.

[0054] The nonlinear deadband control loop receives the steam generator's liquid level difference signal and outputs a second opening signal to limit further opening or closing of the turbine's intake control valve. When the absolute value of the steam generator's liquid level difference is less than a certain deadband limit, the liquid level fluctuation is considered within the allowable range. At this point, the opening signal output by the nonlinear deadband control loop is zero, having no effect on the turbine's intake control valve. When the absolute value of the steam generator's liquid level difference exceeds a certain deadband limit, the liquid level fluctuation is considered to exceed the allowable range. The nonlinear deadband control loop outputs an opening signal to limit excessive operation of the intake control valve, thereby reducing drastic fluctuations in the steam generator's liquid level. When the steam generator's liquid level difference fluctuates beyond the allowable range, the liquid level difference becomes linearly related to the intake valve opening. That is, the greater the steam generator's liquid level difference, the greater the second opening signal for the intake control valve that needs to be limited. This effectively improves the control quality of the steam generator's liquid level at the expense of reduced load power response.

[0055] Among them, the feed water controller is used to determine the third opening signal according to the liquid level difference, feed water flow and steam flow of the steam generator, specifically including: determining the expected feed water flow for compensating for the liquid level fluctuation of the steam generator according to the liquid level difference of the steam generator; determining the third opening signal according to the expected feed water flow, feed water flow and steam flow, and controlling the opening of the feed water regulating valve to achieve the supply of the expected feed water flow.

[0056] Specifically, the feedwater controller receives the liquid level difference signal, the feedwater flow signal, and the steam flow signal to form a three-impulse cascade-feedforward composite control structure, such as Figure 3 As shown, Figure 3 This is a schematic diagram of the three-impulse cascade-feedforward composite control method for the water supply controller provided by the present invention.

[0057] The liquid level controller receives a liquid level difference signal formed by the difference between the given liquid level (preset liquid level) and the measured liquid level of the steam generator. It uses PID control or neural network control strategies to online calculate the desired feedwater flow signal required to compensate for the liquid level fluctuations of the steam generator. The feedwater regulating valve opening controller (i.e., valve opening controller) receives the desired feedwater flow signal, the feedwater flow signal, and the steam flow signal. It uses PI control or other advanced control strategies to online calculate the third opening signal of the feedwater regulating valve required to provide the desired feedwater flow. The third opening signal drives the feedwater regulating valve to achieve feedwater flow regulation. The steam flow signal feedforward is set to address steam flow fluctuations caused by the sudden operation of the turbine inlet regulating valve, eliminating the disturbing effect of steam flow on the steam generator liquid level.

[0058] Among them, the feedforward control link is used to determine the fourth opening signal according to the power difference of the turbine, specifically including: using the proportional integral control strategy to determine the fourth opening signal according to the power difference to control the opening of the feed water regulating valve to achieve the regulation of the feed water flow.

[0059] Specifically, the feedforward control link (feedwater feedforward control link) is set to further improve the response speed of the steam generator feedwater control and reduce the liquid level fluctuation of the steam generator. The feedwater feedforward control link receives the power difference signal between the external load power and the actual power of the steam turbine, adopts the PI control strategy, and calculates the fourth opening signal of the feedwater regulating valve online according to the power difference signal. The fourth opening signal drives the feedwater regulating valve to achieve feedwater flow regulation. The feedwater feedforward control link can issue a feedwater flow compensation action instruction when there is a power difference between the external load power and the actual power of the steam turbine. Compared with the steam generator feedwater controller, which needs to wait until the steam generator has a liquid level difference or steam flow fluctuation feedforward compensation to take effect, the feedwater feedforward control link driven by the turbine power difference signal directly and immediately responds to the external load power signal, which can effectively improve the response speed of the steam generator feedwater control and reduce the liquid level fluctuation of the steam generator.

[0060] The water supply controller also includes a water supply pump speed controller, which is used to determine the water supply pump speed signal based on the pressure difference error of the water supply regulating valve, and adjust the speed of the water supply pump so that the pressure difference error is less than a preset threshold; wherein, the pressure difference error is the difference between the front and rear pressure difference setting value of the water supply regulating valve and the front and rear pressure difference actual measured value.

[0061] Specifically, the water supply pump speed controller receives a pressure difference error signal formed by the difference between the pressure difference setting value before and after the water supply regulating valve and the actual pressure difference measurement value before and after the water supply regulating valve, and adopts PI control or other advanced control strategies to online calculate the water supply pump speed signal required to meet the pressure difference setting value before and after the water supply regulating valve, so as to ensure that the water supply pressure and the pressure difference before and after the water supply regulating valve meet the water supply control performance requirements.

[0062] Among them, the reactor power controller is used to determine the first action signal based on the average coolant temperature difference, reactor power and steam flow, including: determining the required power of the reactor based on the sum of the output after proportional integral control of the average coolant temperature difference and the steam flow; generating the first action signal based on the difference between the required power and the reactor power to achieve control of the control rod.

[0063] Specifically, the reactor power controller receives a coolant average temperature difference signal, a steam flow signal, and a reactor power signal formed by subtracting a coolant average temperature setting signal from a coolant average temperature signal. Figure 4 As shown, Figure 4This is a schematic diagram of the reactor power control method provided by the present invention. The coolant average temperature difference signal, after undergoing proportional and integral control, is summed with the steam flow rate signal to calculate a demand power signal, where K1 is the proportional coefficient and τ is the integral time constant. The demand power signal is subtracted from the reactor power signal to produce a reactor power difference signal. This power difference signal drives the rod speed control program, which calculates a first action signal to adjust the control rod insertion and extension, thereby regulating the reactor's output power.

[0064] Among them, the proportional differential control link is used to determine the second action signal according to the external load power of the turbine, including: using the proportional differential strategy to determine the second action signal according to the external load power to achieve control of the control rod.

[0065] Specifically, the reactor's proportional-differential control receives an external load power signal and, through the proportional-differential control link, calculates a second action signal for driving the control rod downward or upward. This proportional-differential control link issues a control rod movement compensation signal whenever the external load power changes. Unlike reactor power controllers that wait for fluctuations in coolant average temperature, steam flow, or reactor power to take effect, the proportional-differential control link, driven by the external load power signal, responds immediately to the external load power signal. This effectively improves the response speed of reactor power control and compensates for inertial delays in control rod movement.

[0066] The coolant average temperature setting calculation module (i.e., the first calculation module) calculates the coolant average temperature setting value for high and low operating conditions. In low operating conditions, the steam pressure and steam temperature are relatively high, and the fluctuations in steam pressure and steam temperature caused by changes in load power are also large. Therefore, an operating mode in which the coolant average temperature setting value varies linearly with the load power is adopted. In high operating conditions, the steam pressure and steam temperature are relatively low, and the fluctuations in steam pressure and steam temperature caused by changes in load power are also small. Therefore, an operating mode in which the coolant average temperature setting value is constant is adopted.

[0067] Figure 5 This is a schematic diagram of the coolant average temperature setting calculation module provided by the present invention, such as Figure 5 As shown, the set value of the average coolant temperature is described as a function of the steam flow rate (steam flow rate is usually used to represent the load power):

[0068]

[0069] Among them, F s Indicates the value of steam flow, T avf Indicates the average coolant temperature setting value, F s1 F is the critical point for dividing high and low working conditions.s Less than F s1 It belongs to low working condition, which is greater than or equal to F s1 When it is high working condition, T1 represents the coolant average temperature setting value corresponding to the steam flow rate of zero, and T2 represents the steam flow rate of F s1 The corresponding average coolant temperature setting value.

[0070] The coolant average temperature calculation module (second calculation module) is used to calculate the coolant average temperature.

[0071] Specifically, the coolant average temperature calculation module receives the coolant hot end temperature and the coolant cold end temperature, and obtains the coolant average temperature value after arithmetic average calculation. The calculation formula is:

[0072]

[0073] Among them, T av Indicates the steam flow value output by the coolant average temperature calculation module, T h 、T c They respectively represent the coolant hot end temperature value and cold end temperature value input by the coolant average temperature calculation module.

[0074] In summary, the present invention proposes a control method and system for a reactor-following turbine mode. The control system designed based on this control method primarily includes a reactor power controller, a feedwater controller, a turbine controller, a nonlinear deadband control link, a feedforward control link, a proportional-differential control link, a coolant average temperature setting and calculation module, and a coolant average temperature calculation module. The turbine power difference signal enters the turbine controller, the steam generator liquid level difference signal enters the nonlinear dead band control link, the output signal of the turbine controller is subtracted from the output signal of the nonlinear dead band control link and serves as the total air intake control valve opening signal to drive the turbine air intake control valve, the steam generator liquid level difference signal, the feed water flow signal and the steam flow signal enter the feed water controller, the turbine power difference signal enters the feed forward control link, the output signal of the feed water controller and the output signal of the feed forward control link are summed and serve as the total feed water control valve opening signal to drive the feed water control valve, the coolant average temperature difference signal, the stack power signal and the steam flow signal enter the stack power controller, the load power signal enters the proportional differential control link, the output signal of the stack power controller and the output signal of the proportional differential control link are summed and serve as the total control rod action signal to drive the control rod, thereby ultimately achieving the coordinated control goals of taking into account the three aspects of load power tracking performance, steam generator liquid level fluctuation, and feed water control and stack power control response speed.

[0075] It should be noted that the control system of the stack-following machine mode provided in the embodiment of the present invention can execute any of the above-mentioned control methods of the stack-following machine mode during specific operation, which will not be elaborated in this embodiment.

[0076] Figure 6 Schematic diagram of the structure of the electronic device provided by the present invention, such as Figure 6 As shown, the electronic device may include: a processor 610, a communication interface 620, a memory 630 and a communication bus 640, wherein the processor 610, the communication interface 620 and the memory 630 communicate with each other via the communication bus 640. The processor 610 may call the logic instructions in the memory 630 to execute the control method of the stack-following mode, the method comprising: determining the intake regulating valve opening signal according to the difference between the first opening signal and the second opening signal to realize the opening control of the intake regulating valve of the steam turbine; the first opening signal is determined according to the power difference between the external load power and the actual power of the steam turbine, and the second opening signal is determined according to the fluctuation of the liquid level difference between the preset liquid level and the actual liquid level of the steam generator; and, determining the feed water regulating valve opening signal according to the sum of the third opening signal and the fourth opening signal to realize the opening control of the steam generator. the opening control of the feed water regulating valve; the third opening signal is determined according to the liquid level difference, feed water flow and steam flow of the steam generator, and the fourth opening signal is determined according to the power difference of the turbine; and, according to the sum of the first action signal and the second action signal, the control rod action signal is determined to achieve control of the control rod of the reactor; the first action signal is determined according to the average coolant temperature difference, the reactor power and the steam flow, and the second action signal is determined according to the external load power of the turbine; the average coolant temperature difference is the difference between the coolant average temperature set value and the coolant average temperature.

[0077] On the other hand, the present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the control method for the stack-following mode provided in the above-mentioned embodiments, the method comprising: determining an intake regulating valve opening signal according to a difference between a first opening signal and a second opening signal to realize opening control of the intake regulating valve of the steam turbine; the first opening signal is determined according to the power difference between the external load power and the actual power of the steam turbine, and the second opening signal is determined according to the fluctuation of the liquid level difference between the preset liquid level and the actual liquid level of the steam generator; and determining, according to the sum of the third opening signal and the fourth opening signal, A feedwater regulating valve opening signal is used to control the opening of the feedwater regulating valve of the steam generator; the third opening signal is determined based on the liquid level difference, feedwater flow rate and steam flow rate of the steam generator, and the fourth opening signal is determined based on the power difference of the turbine; and a control rod action signal is determined based on the sum of the first action signal and the second action signal to control the control rods of the reactor; the first action signal is determined based on the average coolant temperature difference, the reactor power and the steam flow rate, and the second action signal is determined based on the external load power of the turbine; the average coolant temperature difference is the difference between the coolant average temperature set value and the coolant average temperature.

[0078] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, i.e., they may be located in one location or distributed across multiple network units. Some or all of the modules may be selected based on actual needs to achieve the objectives of the present embodiment. Persons of ordinary skill in the art will be able to understand and implement the present invention without inventive effort.

[0079] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, or of course, by hardware. Based on this understanding, the essence of the above technical solution or the part that contributes to the existing technology can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, a magnetic disk, an optical disk, etc., and includes a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute the methods described in each embodiment or certain parts of the embodiments.

[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. A control method for stacking and following machine mode, characterized in that: include: determining an air intake regulating valve opening signal based on a difference between a first opening signal and a second opening signal to control the opening of the air intake regulating valve of the steam turbine; wherein the first opening signal is determined based on a power difference between an external load power and an actual generated power of the steam turbine, and the second opening signal is determined based on fluctuations in a liquid level difference between a preset liquid level and an actual measured liquid level of the steam generator; and determining a feedwater regulating valve opening signal based on the sum of the third opening signal and the fourth opening signal to control the opening of the feedwater regulating valve of the steam generator; the third opening signal is determined based on the liquid level difference, feedwater flow rate, and steam flow rate of the steam generator, and the fourth opening signal is determined based on the power difference of the steam turbine; and Determining a control rod actuation signal based on the sum of the first actuation signal and the second actuation signal to control the control rods of the reactor; the first actuation signal is determined based on the coolant average temperature difference, reactor power, and steam flow rate, and the second actuation signal is determined based on the external load power of the steam turbine; the coolant average temperature difference is the difference between the coolant average temperature set value and the coolant average temperature; The first opening signal is determined according to the power difference between the external load power and the actual power of the steam turbine, including: With the power difference of the steam turbine being zero as the goal, determining a first opening signal to control the opening of the air intake regulating valve; and, Determining a second opening signal according to fluctuations in the liquid level difference between a preset liquid level and an actual liquid level of the steam generator includes: When the absolute value of the liquid level difference is less than or equal to the preset dead zone limit value, a second opening signal having no regulating effect on the opening of the intake regulating valve is generated; When the absolute value of the liquid level difference is greater than the preset dead zone limit value, a second opening signal is generated, the magnitude of which is positively correlated with the magnitude of the absolute value; The third opening signal is determined based on the liquid level difference, feed water flow rate, and steam flow rate of the steam generator, including: determining a desired feedwater flow rate for compensating for liquid level fluctuations of the steam generator based on the liquid level difference of the steam generator; determining a third opening signal according to the desired feedwater flow rate, the feedwater flow rate, and the steam flow rate, and controlling the opening of the feedwater regulating valve to achieve the supply of the desired feedwater flow rate; and The fourth opening signal is determined based on the power difference of the steam turbine, including: Using the proportional-integral control strategy, according to the power difference, the fourth opening signal is determined to control the opening of the water supply regulating valve to achieve the regulation of the water supply flow; Determining a first action signal according to the coolant average temperature difference, reactor power, and steam flow rate includes: determining the required power of the reactor according to the sum of the output after proportional-integral control of the coolant average temperature difference and the steam flow rate; generating a first action signal according to a difference between the required power and the reactor power to control the control rod; and Determining a second action signal according to the external load power of the steam turbine includes: A proportional-differential strategy is used to determine a second action signal according to the external load power to achieve control of the control rod.

2. The control method of the stacking machine mode according to claim 1, characterized in that: Also includes: Determining a water supply pump speed signal according to a pressure difference error of the water supply regulating valve, and adjusting the speed of the water supply pump so that the pressure difference error is less than a preset threshold; The pressure difference error is the difference between the front and rear pressure difference setting value of the water supply regulating valve and the front and rear pressure difference actual measured value.

3. The control method of the stacking machine mode according to claim 1, characterized in that: The formula for calculating the coolant average temperature setting value is: Among them, F s Indicates the value of steam flow, T avf Indicates the average coolant temperature setting value, F s1 F is the critical point for dividing high and low working conditions. s Less than F s1 It belongs to low working condition, which is greater than or equal to F s1 When it is high working condition, T1 represents the coolant average temperature setting value corresponding to the steam flow rate of zero, and T2 represents the steam flow rate of F s1 The corresponding average coolant temperature setting value.

4. The control method of the stacking machine mode according to claim 1, characterized in that: The average coolant temperature is the arithmetic average of the coolant hot end temperature and the coolant cold end temperature.

5. A control system for stacker-follower mode, characterized in that: The control method of the stacking machine mode according to any one of claims 1 to 4 comprises: a first control module, a second control module and a third control module; a first control module, configured to determine an air intake regulating valve opening signal based on a difference between a first opening signal and a second opening signal, so as to control the opening of the air intake regulating valve of the steam turbine; wherein the first opening signal is determined based on a power difference between an external load power and an actual generated power of the steam turbine, and the second opening signal is determined based on fluctuations in a liquid level difference between a preset liquid level and an actual measured liquid level of the steam generator; and a second control module, configured to determine a feedwater regulating valve opening signal based on a sum of a third opening signal and a fourth opening signal, so as to control the opening of the feedwater regulating valve of the steam generator; the third opening signal being determined based on a liquid level difference, a feedwater flow rate, and a steam flow rate of the steam generator, and the fourth opening signal being determined based on a power difference of the steam turbine; and The third control module is used to determine the control rod action signal based on the sum of the first action signal and the second action signal to achieve control of the control rods of the reactor; the first action signal is determined based on the coolant average temperature difference, reactor power and steam flow, and the second action signal is determined based on the external load power of the turbine; the coolant average temperature difference is the difference between the coolant average temperature set value and the coolant average temperature.

6. The control system of the stacking machine mode according to claim 5, characterized in that: Also includes: a first computing module; The first calculation module is used to calculate the coolant average temperature setting value using a calculation formula for the coolant average temperature setting value; the calculation formula is specifically: Among them, F s Indicates the value of steam flow, T avf Indicates the average coolant temperature setting value, F s1 F is the critical point for dividing high and low working conditions. s Less than F s1 It belongs to low working condition, which is greater than or equal to F s1 When it is high working condition, T1 represents the coolant average temperature setting value corresponding to the steam flow rate of zero, and T2 represents the steam flow rate of F s1 The corresponding average coolant temperature setting value.

7. The control system of the stacking machine mode according to claim 5, characterized in that: Also includes: a second computing module; The second calculation module is used to determine the coolant average temperature according to the arithmetic mean of the coolant hot end temperature and the coolant cold end temperature.

Images