Control system for assisting closed-loop continuous regulation of feed water flow

Abstract

The invention belongs to the technical field of nuclear power station automatic control, and particularly relates to an auxiliary feed water flow closed-loop continuous regulation control system which comprises a liquid level automatic control mode 1 / 2 switching instruction module 01 used for selecting a liquid level control mode; the power detector module 02 is used for realizing reactor core power measurement; the threshold comparator module 03 is used for calculating and comparing the output value of the module 02; the switching value logic and operation module 04 is used for receiving output values of the module 01 and the module 03 and outputting an output value of the module 04; the valve fixed opening operation module 05 is used for realizing valve fixed opening logic control; the valve opening automatic adjustment operation module 06 is used for realizing automatic continuous opening logic control of the valve; and the switching value switching operation module B08 selects the output value of the receiving module 06 or the output value of the receiving module 05 according to the output value of the module 04. Automatic and continuous adjustment of the valve is achieved, and it is ensured that the liquid level of the steam generator is accurately controlled at an expected value.

Description

Technical Field

[0001] The invention belongs to the technical field of nuclear power plant automatic control, and in particular relates to a control system for closed-loop continuous regulation of auxiliary feedwater flow. Background Art

[0002] The auxiliary feedwater system (TFA) is a dedicated safety facility system. When the normal feedwater system fails, or when a power plant accident causes the normal feedwater system to be abnormal or even unavailable, or when the reactor is started and the reactor coolant system is heated up or hot shut down, the auxiliary feedwater system replaces the main feedwater system (TFM) and the startup feedwater system (TFS) and is put into operation. The heat of the reactor coolant system is transferred to the secondary circuit system through the steam generator supplied by the auxiliary feedwater system to generate steam; the secondary circuit steam is discharged into the condenser or discharged to the atmosphere through the turbine bypass system (TSC / TSA) to remove the residual heat from the core until the residual heat removal system (RHR) reaches a state where it can be put into operation.

[0003] TFA012, 013, 014, 015, 016, 017VD are air-failure-open pneumatic control valves. Each control valve is equipped with a solenoid valve (column A or column B). The solenoid valves of control valves TFA012, 014, 016VD are powered by column A, and the solenoid valves of control valves TFA013, 015, 017VD are powered by column B. When the solenoid valve loses power, the pneumatic valve is fully open. When the solenoid valve is powered, the pneumatic valve is in the adjustment mode. This control can make the valve quickly fully open or adjust under the action of the valve electrical converter and positioner.

[0004] In previous nuclear power plant designs, the auxiliary water supply system had the following characteristics:

[0005] The regulating valve only has the operator manual adjustment mode, or has both the operator manual adjustment and automatic step-by-step adjustment modes. Within half an hour after the accident, the flow rate is adjusted automatically step by step. In addition, the operator can also exit the automatic step-by-step adjustment mode by manual operation. In the automatic step-by-step adjustment mode, the valve opening is controlled by the 4-20mA signal given to the electrical converter. When the evaporator liquid level reaches the high-high threshold (75% narrow range water level), the valve step adjustment enters the low flow mode, that is, the electrical converter is fixed to output 30% of the valve opening. When the evaporator liquid level reaches the low water level (25% narrow range water level), the electrical converter is fixed to output 100% of the valve opening until the evaporator liquid level high-high signal appears again, and the valve is automatically controlled to step and adjust to 30% opening again.

[0006] Under normal circumstances, regulating valves 012VD to 017VD maintain 100% opening, and are 100% open after receiving the signal from the reactor protection system (RRP). After these valves are reset, the solenoid valves are energized and their openings are automatically controlled in steps through the steam generator liquid level, but can only maintain 30% and 100% opening.

[0007] At the same time, the opening of these valves can be manually adjusted in the main control room to adjust the flow entering each steam generator.

[0008] The automatic control logic design of the A / B column outlet flow regulating valve of the original auxiliary water supply system only has 100% and 30% opening, and is for regulation under accident conditions, such as:

[0009] When one of the three steam generators detects a low water level in the steam generator water level channel 2 / 4 and a low main feed water flow rate in the corresponding steam generator, the two electric pumps and two steam-driven pumps of TFA receive an automatic start signal from RRP, and the pump outlet flow regulating valve is fully opened;

[0010] If the low water level detected by the water level channel 2 / 4 of one of the three steam generators is maintained for 8 minutes, the two electric pumps and two pneumatic pumps will automatically start, and the pump outlet flow regulating valve will be fully opened;

[0011] During the water supply of the auxiliary water supply system, when the low water level signal from the RRP system steam generator is triggered, a control demand command for the regulating valve is generated, the solenoid valve is energized, and enters the regulation mode. A 20mA signal is output to the electrical converter through the DCS card to control the regulating valve to open 100% to supply water to the steam generator; when the high water level 2 signal from the RRP system steam generator is triggered, a small signal is fixedly output to the electrical converter through the DCS card to control the regulating valve to open 30% to supply water to the steam generator.

[0012] According to the current operating habits and experience of operators, when the nuclear power plant is started, the TFA electric pump or steam-driven pump can replace the startup water supply system to maintain the water level of the steam generator. This water level should be close to (±5%) the recommended water level under zero load (33% of the narrow range), and also used to compensate for the loss of secondary circuit water caused by the startup operation. At this time, the operator must put the valve in the adjustment mode based on personal observation and judgment of the power plant operation parameters, manually adjust the opening of the auxiliary water supply flow regulating valve, and control the auxiliary water supply flow without using step-by-step automatic control. This operation mode requires the operator to work hard, which increases the operator's workload and also increases the probability of accidents caused by human errors.

[0013] In order to meet the above requirements, further improve the safety of auxiliary water supply and reduce the degree of human intervention, corresponding improvement measures need to be taken to ensure that the evaporator liquid level is maintained at the set value and does not overflow by continuously and automatically adjusting the opening of the auxiliary water supply flow control valve. Summary of the invention

[0014] The purpose of the present invention is to provide a control system for closed-loop continuous regulation of auxiliary feed water flow, which can ensure that the liquid level of the steam generator is accurately controlled at the expected value, reduce the risk of errors introduced by manual control by the operator, meet the requirement of no human intervention within a certain period of time, effectively solve the potential risks of the auxiliary feed water function of nuclear power plants in the past, reduce the impact of human intervention factors on the stability of power plant operation, and improve the effectiveness of the auxiliary feed water system and the safety level of power plant operation.

[0015] The technical solution to achieve the purpose of the present invention is:

[0016] A control system for closed-loop continuous regulation of auxiliary water supply flow, the system comprising:

[0017] Liquid level automatic control mode 1 / 2 switching command module, used to select the liquid level control mode;

[0018] Power detector module, used to measure the reactor core power;

[0019] A threshold comparator module, used for performing calculation and comparison on the output value of the power detector module;

[0020] The switch logic and operation module receives the output values ​​of the liquid level automatic control mode 1 / 2 switching instruction module and the threshold comparator module, and outputs the output value of the switch logic and operation module according to the output values ​​of the liquid level automatic control mode 1 / 2 switching instruction module and the threshold comparator module;

[0021] The valve fixed opening calculation module is used to realize the valve fixed 30% or 100% opening logic control;

[0022] The valve opening automatic adjustment calculation module is used to realize the valve 0-100% automatic continuous opening logic control;

[0023] The switch quantity switching operation module B receives the output value of the switch quantity logic and operation module as the input control signal of the switch quantity switching operation module B. According to the output value of the switch quantity logic and operation module, it selects to receive the output value of the valve opening automatic adjustment operation module to realize automatic adjustment of the valve opening, or receives the output value of the valve fixed opening operation module to realize fixed valve opening.

[0024] The liquid level automatic control mode 1 / 2 switching instruction module includes two modes: mode 1 and mode 2. Mode 1 selects to execute the valve fixed opening operation module, at which time the output value of the liquid level automatic control mode 1 / 2 switching instruction module is 0; mode 2 selects to execute the valve opening automatic adjustment operation module, at which time the output value of the liquid level automatic control mode 1 / 2 switching instruction module is 1;

[0025] If the core power is ≤2, the output value of the threshold comparator module is 1, otherwise the output value is 0;

[0026] The switch logic and operation module, when the output values ​​of the received liquid level automatic control mode 1 / 2 switching instruction module and the threshold comparator module are both 1, the output value is 1; when the received output value of the liquid level automatic control mode 1 / 2 switching instruction module or the threshold comparator module is equal to 0, the output value is equal to 0;

[0027] When the output of the switch logic and operation module is 1, the switch switching operation module B receives the output value of the valve opening automatic adjustment operation module to realize automatic adjustment of the valve opening; when the output of the switch logic and operation module is 0, the switch switching operation module B receives the output value of the valve fixed opening operation module to realize fixed valve opening.

[0028] The valve fixed opening operation module includes: an evaporator liquid level logic judgment operation module, an RS trigger operation module A, a switch value logic or operation module, an analog value assignment module A, a switch value switching operation module, and an RS trigger operation module B;

[0029] The evaporator liquid level logic judgment operation module judges the evaporator liquid level height in real time. If the evaporator liquid level is low, the SG liquid level low outputs 1; if the evaporator liquid level is high, the SG liquid level high outputs 1;

[0030] RS trigger operation module A receives the output value of the evaporator liquid level logic judgment operation module. If the SG liquid level is low and outputs 1, the RS trigger operation module A outputs 1. If the SG liquid level is high and outputs 1, the RS trigger operation module A outputs 0.

[0031] The switch logic or operation module receives the output value of the evaporator liquid level logic judgment operation module. As long as at least one of the SG liquid level low and SG liquid level high outputs 1, the switch logic or operation module outputs 1;

[0032] Analog value assignment module A is used to set the fixed opening of the valve, which can be 30% or 100%;

[0033] The switch quantity switching operation module receives the output value of the RS trigger operation module A and the fixed valve opening set by the analog value assignment module A. The output value of the RS trigger operation module A is used as the input control signal of the switch quantity switching operation module, and the fixed valve opening set by the analog value assignment module A is selected according to the output value of the RS trigger operation module A.

[0034] The RS trigger operation module B receives the output value of the switch logic or operation module. If the output value of the switch logic or operation module is 1, the output value of the RS trigger operation module B is 1.

[0035] The switch quantity switching operation module outputs a 100% fixed opening if the output value of the RS trigger operation module A is 1, and outputs a 30% fixed opening if the output value of the RS trigger operation module A is 0.

[0036] The valve fixed opening calculation module also includes: a soft hand operator calculation module A, which is used to realize manual / fixed valve opening control. If the manual valve opening control is performed, the T output value in the soft hand operator calculation module A is 1, and if the fixed valve opening control is performed, the T output value in the soft hand operator calculation module A is 0;

[0037] The RS trigger operation module B receives the output value of the soft hand operator operation module A. If the soft hand operator operation module A outputs 1, the output value of the RS trigger operation module B is 0.

[0038] The control system further comprises: a switch quantity switching operation module A, which receives the output value of the RS trigger operation module B, and the output value of the RS trigger operation module B is an input control signal of the switch quantity switching operation module A; when the output value of the RS trigger operation module B is 1, the switch quantity switching operation module A receives the output value of the switch quantity switching operation module, and outputs the output value of the switch quantity switching operation module to the switch quantity switching operation module B; when the output value of the RS trigger operation module B is 0, the switch quantity switching operation module A receives a 100% fixed opening signal of the analog value assignment module A;

[0039] When the output of the switch value logic and operation module is 0, the switch value switching operation module B receives the output value of the switch value switching operation module A to achieve a fixed valve opening.

[0040] The control system also includes: a switch quantity switching operation module C, which receives the output value of T in the soft hand operator operation module A, and the output value of T in the soft hand operator operation module A is used as an input control signal of the switch quantity switching operation module C; when the output value of T in the soft hand operator operation module A is 1, the switch quantity switching operation module C selects the output value of A in the soft hand operator operation module A, and outputs the output value of A in the soft hand operator operation module A to the valve control output module, so as to directly control the valve opening; when the output value of T in the soft hand operator operation module A is 0, the switch quantity switching operation module C selects the output value of the switch quantity switching operation module B, and outputs the output value of the switch quantity switching operation module B to the valve control output module, so as to directly control the valve by the output value of the switch quantity switching operation module B.

[0041] The valve opening automatic adjustment operation module includes: an evaporator liquid level measurement module, an analog value assignment module B, a switch value switching operation module, a PID control operation module, and a soft hand operator operation module B;

[0042] The evaporator liquid level measurement module is used to measure the evaporator liquid level in real time to obtain the output value of the evaporator liquid level measurement module, and transmit it to the PID control operation module in real time;

[0043] Analog value assignment module B is used to set the liquid level control of the evaporator liquid level;

[0044] The soft hand operator operation module B is used to realize manual / continuous valve opening control. If manual valve opening control is performed, the output value of T in the soft hand operator operation module B is 1. If continuous valve opening control is performed, the output value of T in the soft hand operator operation module B is 0.

[0045] The switch quantity switching operation module receives the output value of T in the soft hand operator operation module B, the output value of A in the soft hand operator operation module B and the set value of the analog value assignment module B; selects the output value of A in the soft hand operator operation module B or the set value of the analog value assignment module B according to the output value of T in the soft hand operator operation module B, and outputs it to the PID control operation module;

[0046] The PID control operation module compares the output value of the evaporator liquid level measurement module with the output value of the switch quantity switching operation module in real time, outputs different analog values, and performs real-time continuous control of the valve opening;

[0047] When the output of the switch quantity logic and operation module is 1, the switch quantity switching operation module B receives the output value of the PID control operation module in the valve opening automatic adjustment operation module to realize the automatic adjustment of the valve opening.

[0048] The switch quantity switching operation module receives the output value of T in the soft hand operator operation module B, and uses the output value of T in the soft hand operator operation module B as the input control signal of the switch quantity switching operation module; when the output value of T in the soft hand operator operation module B is 1, the switch quantity switching operation module selects the output value of A in the soft hand operator operation module B, and outputs the output value of A in the soft hand operator operation module B to the PID control operation module; when the output value of T in the soft hand operator operation module B is 0, the switch quantity switching operation module selects the internal given value of the analog quantity assignment module B, and outputs the internal given value of the analog quantity assignment module B to the PID control operation module.

[0049] The PID control operation module compares the output value of the evaporator liquid level measurement module with the output value of the switch quantity switching operation module in real time, and outputs different analog values: if the values ​​of the evaporator liquid level measurement module and the switch quantity switching operation module are consistent, the output of the PID control operation module remains at the current value and does not change; if the value of the evaporator liquid level measurement module is greater than the value of the switch quantity switching operation module, the output value of the PID control operation module decreases until the values ​​of the evaporator liquid level measurement module and the switch quantity switching operation module are consistent; if the value of the evaporator liquid level measurement module is less than the value of the switch quantity switching operation module, the output value of the PID control operation module increases until the values ​​of the evaporator liquid level measurement module and the switch quantity switching operation module are consistent.

[0050] The beneficial technical effects of the present invention are:

[0051] 1. In a control system for closed-loop continuous regulation of auxiliary feed water flow provided by the present invention, the design of automatic continuous regulation can be used in the startup phase of the power plant. When the TFA electric pump or pneumatic pump can be used to replace the startup feed water system to maintain the water level of the steam generator, it can replace the operator to manually control the valve opening, ensure that the liquid level of the steam generator is accurately controlled at the expected value, reduce the risk of errors introduced by the operator's manual control, meet the requirement of no human intervention within a certain period of time, and do not affect the original control logic of the regulating valve; solve the potential risks of the auxiliary feed water function of nuclear power plants in the past, reduce the impact of human intervention factors on the stability of power plant operation, and improve the effectiveness of the auxiliary feed water system and the safety level of power plant operation.

[0052] 2. The present invention provides a control system for closed-loop continuous regulation of auxiliary water supply flow. Based on the traditional valve fixed opening operation module, an automatic valve opening adjustment operation module is added. The evaporator liquid level is monitored in real time through the evaporator liquid level measurement module. After setting the required steam generator liquid level through the analog value assignment module B, the system automatically calculates through the switch quantity switching operation module, the PID control operation module, and the soft hand operator operation module B to adjust the valve opening in real time so that the evaporator liquid level is maintained at the set required liquid level.

[0053] 3. The present invention provides a control system for closed-loop continuous regulation of auxiliary water flow. Through the liquid level automatic control mode 1 / 2 switching command module, the user can select the liquid level control mode in real time. When mode 1 is selected, the valve fixed opening operation module is executed, and when mode 2 is selected, the valve opening automatic adjustment operation module is executed. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 A schematic diagram of a control system for closed-loop continuous regulation of auxiliary water flow provided by the present invention;

[0055] In the figure: 01-liquid level automatic control mode 1 / 2 switching instruction module; 02-power detector module; 03-threshold comparator module; 04-switching quantity logic and operation module; 05-valve fixed opening operation module; 06-valve opening automatic adjustment operation module; 07-switching quantity switching operation module A; 08-switching quantity switching operation module B; 09-switching quantity switching operation module C; 10-valve control output module; 051-evaporator liquid level logic judgment operation module; 052-RS trigger operation module A; 053-switching quantity logic or operation module; 054-analog value assignment module A; 055-switching quantity switching operation module; 056-RS trigger operation module B; 057-soft hand operator operation module A;

[0056] 061-evaporator liquid level measurement module; 062-analog value assignment module B; 063-switch quantity switching operation module; 064-PID control operation module; 065-soft hand operator operation module B. DETAILED DESCRIPTION

[0057] The present invention is further described in detail below with reference to the accompanying drawings and embodiments.

[0058] like Figure 1 As shown, the present invention provides a control system for closed-loop continuous regulation of auxiliary water supply flow, including: a liquid level automatic control mode 1 / 2 switching instruction module 01, a power detector module 02, a threshold comparator module 03, a switch value logic and operation module 04, a valve fixed opening operation module 05, a valve opening automatic adjustment operation module 06, a switch value switching operation module A07, a switch value switching operation module B08, a switch value switching operation module C09, and a valve control output module 10.

[0059] The liquid level automatic control mode 1 / 2 switching instruction module 01 is used to select the liquid level control mode; it includes two modes: mode 1 and mode 2. Mode 1 selects to execute the valve fixed opening operation module 05, at this time the instruction module output value is 0, mode 2 selects to execute the valve opening automatic adjustment operation module 06, at this time the instruction module output value is 1. The liquid level automatic control mode 1 / 2 switching instruction module 01 is selected by the user, and the default is mode 1.

[0060] Power detector module 02, used to measure reactor core power;

[0061] The threshold comparator module 03 is used to perform calculation and comparison on the output value of the power detector module 02. If the core power is ≤ 2, the output value of the threshold comparator module 03 is 1, otherwise the output value is 0;

[0062] The switch logic and operation module 04 receives the output values ​​of the liquid level automatic control mode 1 / 2 switching instruction module 01 and the threshold comparator module 03 as the input values ​​of the switch logic and operation module 04; and outputs the output value of the switch logic and operation module 04 according to the output values ​​of the liquid level automatic control mode 1 / 2 switching instruction module 01 and the threshold comparator module 03.

[0063] The switch logic and operation module 04 checks all connected input values ​​in sequence starting from the first input value. When all received input values ​​are 1, the output value is 1. If an input value equals 0 is encountered, the subsequent inputs are no longer checked and the output value is equal to 0. The output value of the switch logic and operation module 04 is output to the switch switching operation module B08.

[0064] The valve fixed opening calculation module 05 is used to realize the valve fixed 30% or 100% opening logic control.

[0065] The valve opening automatic adjustment calculation module 06 is used to realize the valve opening logic control of 0-100% automatic continuous.

[0066] The switch quantity switching operation module A07 receives the output value of the valve fixed opening operation module 05 as the input control signal of the switch quantity switching operation module A07, and selects the input signal path for output according to the input control signal: if the input control signal is 0, the output is the input end of 0; if the input control signal is 1, the output is the input end of 1.

[0067] The switch quantity switching operation module B08 receives the output value of the switch quantity logic and operation module 04 as the input control signal of the switch quantity switching operation module B08, and selects the input signal path for output according to the output value of the logic and operation module 04: if the input control signal is 0, the output is the input end of 0; if the input control signal is 1, the output is the input end of 1.

[0068] When the output of the switch logic and operation module 04 is 1, the switch switching operation module B08 selects the signal path output of 1, that is, the switch switching operation module B08 receives the output value of the valve opening automatic adjustment operation module 06, and outputs the output value of the valve opening automatic adjustment operation module 06 to the switch switching operation module C09, thereby realizing the automatic adjustment function of the valve opening automatic adjustment operation module 06; when the output of the switch logic and operation module 04 is 0, the switch switching operation module B08 selects the signal path output of 0, that is, the switch switching operation module B08 receives the output value of the switch switching operation module A07, and outputs the output value of the switch switching operation module A07 to the switch switching operation module C09, thereby realizing the valve fixed opening operation function of the valve fixed opening operation module 05.

[0069] The switch quantity switching operation module C09 receives the output value of the soft hand operator operation module A057 as the input control signal of the switch quantity switching operation module C09, and selects the input signal path for output according to the input control signal: if the control signal is 0, the output is the input end of 0. If the control signal is 1, the output is the input end of 1.

[0070] The valve control output module 10 receives the output value of the switch value switching operation module C09 to implement the valve logic control operation.

[0071] In a specific embodiment, the fixed opening mode is selected, the output of the switch logic and operation module 04 is 0, and the output of the soft hand operator operation module A 057 is 0. The input signal of the switch switching operation module B 08 is 0, and the switch switching operation module B 08 selects to receive the signal of the switch switching operation module A07 for output. If the output value of the switch switching operation module A07 is 100%, the switch switching operation module B 08 outputs 100% to the switch switching operation module C09. The input signal of the switch switching operation module C09 is 0, and the switch switching operation module C09 selects to receive the 100% signal of the switch switching operation module B 08 for output. At this time, the opening of the valve is 100%.

[0072] In another specific embodiment, the automatic adjustment mode is selected, the output of the switch quantity logic and operation module 04 is 1, and the output of the soft hand operator operation module A 057 is 0. The input signal of the switch quantity switching operation module B 08 is 1, and the switch quantity switching operation module B 08 selects to receive the signal of the PID control operation module 064 for output. If the output value of the PID control operation module 064 is 50%, the switch quantity switching operation module B 08 outputs 50% to the switch quantity switching operation module C09. The input signal of the switch quantity switching operation module C09 is 0, and the switch quantity switching operation module C09 selects to receive the 50% signal of the switch quantity switching operation module B 08 for output. At this time, the opening of the valve is 50%.

[0073] The valve fixed opening operation module 05 includes: an evaporator liquid level logic judgment operation module 051, an RS trigger operation module A052, a switch quantity logic or operation module 053, an analog value assignment module A054, a switch quantity switching operation module 055, an RS trigger operation module B056; and a soft hand operator operation module A057.

[0074] When the valve fixed opening calculation module 05 is activated, the evaporator liquid level logic judgment calculation module 051 judges the evaporator liquid level height in real time. If the evaporator liquid level is low, the SG liquid level low outputs 1; if the evaporator liquid level is high, the SG liquid level high outputs 1;

[0075] RS trigger operation module A052, used to receive the output value of the evaporator liquid level logic judgment operation module 051, if the SG liquid level is low, it outputs 1, and if the SG liquid level is high, it outputs 1, then it outputs 0;

[0076] The switch value logic or operation module 053 is used to receive the output value of the evaporator liquid level logic judgment operation module 051, and output 1 as long as at least one of the SG liquid level low and SG liquid level high outputs 1;

[0077] Analog value assignment module A054 is used to set the fixed valve opening, which can be 30% or 100%;

[0078] The switch quantity switching operation module 055 receives the output value of the RS trigger operation module A052 and the fixed valve opening set by the analog value assignment module A054. The output value of the RS trigger operation module A052 is used as the input control signal of the switch quantity switching operation module 055. According to the output value of the RS trigger operation module A052, the fixed valve opening set by the analog value assignment module A054 is selected for output;

[0079] If the output value of the RS trigger operation module A052 is 1, the switch quantity switching operation module 055 outputs 100%, and if the output value of the RS trigger operation module A052 is 0, the switch quantity switching operation module 055 outputs 30%.

[0080] The RS trigger operation module B056 receives the output values ​​of the switch logic or operation module 053 and the soft hand operator operation module A057. If the switch logic or operation module 053 outputs 1, the RS trigger operation module B056 outputs 1; if the soft hand operator operation module A057 outputs 1, the RS trigger operation module B056 outputs 0;

[0081] The switch quantity switching operation module A07 receives the output value of the RS trigger operation module B 056, and the output value of the RS trigger operation module B 056 is the input control signal of the switch quantity switching operation module A07; when the output value of the RS trigger operation module B 056 is 1, the switch quantity switching operation module A07 selects the signal path 1 for output, that is, outputs the output value of the switch quantity switching operation module 055 to the switch quantity switching operation module B 08; when the output value of the RS trigger operation module B 056 is 0, the switch quantity switching operation module A07 selects the signal path 0 for output, that is, outputs the 100% signal of the analog value assignment module A054 to the switch quantity switching operation module B 08.

[0082] The soft hand operator operation module A057 is used to realize manual / fixed valve opening control. If manual valve opening control is performed, T in the soft hand operator operation module A057 outputs 1. If fixed valve opening control is performed, T in the soft hand operator operation module A057 outputs 0. The output value of T in the soft hand operator operation module A057 is output to the switch quantity switching operation module C09.

[0083] The switch quantity switching operation module C 09 receives the output value of T in the soft hand operator operation module A057, and the output value of T in the soft hand operator operation module A057 is used as the input control signal of the switch quantity switching operation module C 09; when the output value of T in the soft hand operator operation module A 057 is 1, the switch quantity switching operation module C 09 selects the signal path output of 1, that is, outputs the output value of A in the soft hand operator operation module A 057 to the valve control output module 10, and directly controls the valve opening; when the output value of T in the soft hand operator operation module A 057 is 0, the switch quantity switching operation module C 09 selects the signal path output of 0, that is, outputs the signal of the switch quantity switching operation module B 08 to the valve control output module 10, and the valve is directly controlled by the output data of the switch quantity switching operation module B08.

[0084] The valve opening automatic adjustment operation module 06 includes: an evaporator liquid level measurement module 061, an analog value assignment module B062, a switch value switching operation module 063, a PID control operation module 064, and a soft hand operator operation module B065.

[0085] When the valve opening automatic adjustment operation module 06 is activated, the evaporator liquid level measurement module 061 measures the evaporator liquid level in real time to obtain the output value of the evaporator liquid level measurement module 061, and transmits it to the PID control operation module 064 in real time;

[0086] Analog value assignment module B062, used to set the liquid level control of the evaporator;

[0087] The soft hand operator operation module B065 is used to realize manual / continuous valve opening control. If manual valve opening control is performed, the output value of T in the soft hand operator operation module B065 is 1. If continuous valve opening control is performed, the output value of T in the soft hand operator operation module B065 is 0.

[0088] The switch quantity switching operation module 063 receives the output value of T in the soft hand operator operation module B065, the output value of A (external given value) in the soft hand operator operation module B065, and the setting value of the analog value assignment module B062. The output value of T (internal and external given value switching) in the soft hand operator operation module 065 is used as the input control signal of the switch quantity switching operation module 063, and the input signal path is selected for output according to the input control signal: if the control signal is 0, the output is the input end of 0; if the control signal is 1, the output is the input end of 1.

[0089] The T (internal and external given value switching) output value in the soft hand operator operation module B065 is used as the input control signal of the switch quantity switching operation module 063; when the T (internal and external given value switching) output value of the soft hand operator operation module B 065 is 1, the switch quantity switching operation module 063 selects the signal path output of 1, that is, the output value of A (external given value) in the soft hand operator operation module B 065 is output to the PID control operation module 064; when the T (internal and external given value switching) output value of the soft hand operator operation module B 065 is 0, the switch quantity switching operation module 063 selects the signal path output of 0, that is, the internal given value of the analog value assignment module B 062 is output to the PID control operation module 064.

[0090] The PID control operation module 064 compares the output value of the evaporator liquid level measurement module 061 with the output value of the switch quantity switching operation module 063 in real time. If the values ​​of the evaporator liquid level measurement module 061 and the switch quantity switching operation module 063 are consistent, the output of the PID control operation module 064 remains unchanged at the current value. If the value of the evaporator liquid level measurement module 061 is greater than the value of the switch quantity switching operation module 063, the output value of the PID control operation module 064 decreases until the values ​​of the evaporator liquid level measurement module 061 and the switch quantity switching operation module 063 are consistent; if the value of the evaporator liquid level measurement module 061 is less than the value of the switch quantity switching operation module 063, the output value of the PID control operation module 064 increases until the values ​​of the evaporator liquid level measurement module 061 and the switch quantity switching operation module 063 are consistent. By outputting different analog values, the valve opening is continuously controlled in real time.

[0091] The present invention provides a method for closed-loop continuous automatic control of the evaporator liquid level during the period when the auxiliary water supply system supplies water to the evaporator in the startup phase of the power station. On the basis of the traditional valve fixed opening operation module 05, a valve opening automatic adjustment operation module 06 is added. The evaporator liquid level is monitored in real time through the evaporator liquid level measurement module 061. When the operator sets the required steam generator liquid level through the analog value assignment module B062, the system automatically calculates through the switch quantity switching operation module 063, the PID control operation module 064, and the soft hand operator operation module B065, and adjusts the valve opening in real time so that the evaporator liquid level is maintained at the liquid level required by the operator. At the same time, through the liquid level automatic control mode 1 / 2 switching instruction module 01, the user can select the liquid level control mode in real time. When mode one is selected, the valve fixed opening operation module 05 is executed, and when mode two is selected, the valve opening automatic adjustment operation module 06 is executed. The liquid level automatic control mode 1 / 2 switching instruction module 01 is selected by the user.

[0092] The liquid level automatic control mode 1 / 2 switching instruction module 01 includes two modes: mode 1 and mode 2. Mode 1 executes the valve fixed opening operation module 05, and the instruction module outputs 0 at this time. Mode 2 executes the valve opening automatic adjustment operation module 06, and the instruction module outputs 1 at this time. The liquid level automatic control mode 1 / 2 switching instruction module 01 is selected by the user and defaults to mode 1. At this time, if the user selects mode 2, one of the conditions for starting the valve opening automatic adjustment mode is met. Further, the power detector module 02 is executed to realize the reactor core power measurement, and the threshold comparator module 03 is executed to perform calculation comparison on the output value of the power detector module 02. If the core power is ≤2, the threshold comparator module 03 outputs 1, and another condition for starting the valve opening automatic adjustment mode is met.

[0093] Further, the valve opening automatic adjustment operation module 06 is executed, and the valve opening automatic adjustment operation module 06 includes: an evaporator liquid level measurement module 061, an analog value assignment module B062, a switch value switching operation module 063, a PID control operation module 064, and a soft hand operator operation module B065.

[0094] Furthermore, the evaporator liquid level measurement module 061 measures the evaporator liquid level in real time to obtain the output value of the evaporator liquid level measurement module 061, and transmits it to the PID control operation module 064 in real time;

[0095] Further, the analog value assignment module B062 is used to set the liquid level control of the evaporator liquid level; the switch value switching operation module 063 has three input signals, one of which is an input control signal, which receives the T (internal and external set value switching) output value of the soft hand operator operation module 065. If the T (internal and external set value switching) output value of the soft hand operator operation module 065 is 1, the switch value switching operation module 063 selects the signal path output of 1, that is, the output value of A (external set value) in the soft hand operator operation module 065 is output to the PID control operation module 064. If the T (internal and external set value switching) output value of the soft hand operator operation module 065 is 0, the switch value switching operation module 063 selects the signal path output of 0, that is, the internal set value of the analog value assignment module B062 is output to the PID control operation module 064;

[0096] Further, the PID control operation module 064 compares and judges the output value of the evaporator liquid level measurement module 061 and the output value of the switch quantity switching operation module 063. If the values ​​of the evaporator liquid level measurement module 061 and the switch quantity switching operation module 063 are consistent, the output of the PID control operation module 064 remains unchanged at the current value; if the value of the evaporator liquid level measurement module 061 is greater than the value of the switch quantity switching operation module 063, the output value of the PID control operation module 064 decreases until the values ​​of the evaporator liquid level measurement module 061 and the switch quantity switching operation module 063 are consistent; if the value of the evaporator liquid level measurement module 061 is less than the value of the switch quantity switching operation module 063, the output value of the PID control operation module 064 increases until the values ​​of the evaporator liquid level measurement module 061 and the switch quantity switching operation module 063 are consistent;

[0097] Further, the switch quantity switching operation module B08 has three input signals, one of which is an input control signal, which receives the output value of the switch quantity logic and operation module 04. If the output value of the switch quantity logic and operation module 04 is 1, the switch quantity switching operation module B08 selects the signal path output of 1, and outputs the output value of the PID control operation module 064 in the valve opening automatic adjustment operation module 06 to the switch quantity switching operation module C09, so as to realize the automatic adjustment function of the module 06;

[0098] Furthermore, the switch quantity switching operation module C09 has three input signals, one of which is an input control signal, which receives the output value of the soft hand operator operation module A057. If the output value of the soft hand operator operation module A057 is 1, the switch quantity switching operation module C09 selects the signal path output 1, that is, outputs the output value in the soft hand operator operation module A057 to the valve control output module 10, and directly controls the valve opening. If the output value of the soft hand operator operation module A057 is 0, the switch quantity switching operation module C09 selects the signal path output 0, that is, outputs the signal of the switch quantity switching operation module B08 to the valve control output module 10, and the valve is directly controlled by the output data of the switch quantity switching operation module B08.

[0099] The present invention is described in detail above with reference to the accompanying drawings and embodiments, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge of ordinary technicians in the field without departing from the purpose of the present invention. The contents not described in detail in the present invention can adopt the existing technology.

Claims

1. A control system for closed-loop continuous regulation of auxiliary water flow, characterized in that: The system comprises: Liquid level automatic control mode 1 / 2 switching command module (01), used to select the liquid level control mode; A power detector module (02) is used to measure the reactor core power; A threshold comparator module (03) is used to perform calculation and comparison on the output value of the power detector module (02); A switch value logic and operation module (04) receives the output values ​​of the liquid level automatic control mode 1 / 2 switching instruction module (01) and the threshold comparator module (03), and outputs the output value of the switch value logic and operation module (04) according to the output values ​​of the liquid level automatic control mode 1 / 2 switching instruction module (01) and the threshold comparator module (03); A valve fixed opening calculation module (05) is used to realize the valve fixed 30% or 100% opening logic control; The valve opening automatic adjustment calculation module (06) is used to realize the valve 0-100% automatic continuous opening logic control; The switch quantity switching operation module B (08) receives the output value of the switch quantity logic and operation module (04) as an input control signal of the switch quantity switching operation module B (08), and according to the output value of the switch quantity logic and operation module (04), selects to receive the output value of the valve opening automatic adjustment operation module (06) to realize automatic adjustment of the valve opening, or receives the output value of the valve fixed opening operation module (05) to realize fixed valve opening.

2. A control system for closed-loop continuous regulation of auxiliary water flow according to claim 1, characterized in that: The liquid level automatic control mode 1 / 2 switching instruction module (01) includes two modes: mode 1 and mode 2. Mode 1 selects to execute the valve fixed opening operation module (05), and at this time the output value of the liquid level automatic control mode 1 / 2 switching instruction module (01) is 0; mode 2 selects to execute the valve opening automatic adjustment operation module (06), and at this time the output value of the liquid level automatic control mode 1 / 2 switching instruction module (01) is 1; If the core power is ≤2, the output value of the threshold comparator module (03) is 1, otherwise the output value is 0; The switch logic and operation module (04) outputs 1 when the output values ​​of the received liquid level automatic control mode 1 / 2 switching instruction module (01) and the threshold comparator module (03) are both 1; the output value is 0 when the received output value of the liquid level automatic control mode 1 / 2 switching instruction module (01) or the threshold comparator module (03) is equal to 0; When the output of the switch value logic and operation module (04) is 1, the switch value switching operation module B (08) receives the output value of the valve opening automatic adjustment operation module (06) to realize the automatic adjustment of the valve opening; when the output of the switch value logic and operation module (04) is 0, the switch value switching operation module B (08) receives the output value of the valve fixed opening operation module (05) to realize the valve fixed opening.

3. A control system for closed-loop continuous regulation of auxiliary water flow according to claim 1, characterized in that: The valve fixed opening operation module (05) comprises: an evaporator liquid level logic judgment operation module (051), an RS trigger operation module A (052), a switch value logic or operation module (053), an analog value assignment module A (054), a switch value switching operation module (055), and an RS trigger operation module B (056); The evaporator liquid level logic judgment operation module (051) judges the evaporator liquid level height in real time. If the evaporator liquid level is low, the SG liquid level low outputs 1; if the evaporator liquid level is high, the SG liquid level high outputs 1; The RS trigger operation module A (052) receives the output value of the evaporator liquid level logic judgment operation module (051), and if the SG liquid level is low, the output is 1, and the RS trigger operation module A (052) outputs 1; if the SG liquid level is high, the output is 1, and the RS trigger operation module A (052) outputs 0; The switch value logic or operation module (053) receives the output value of the evaporator liquid level logic judgment operation module (051), and as long as at least one of the SG liquid level low and the SG liquid level high outputs 1, the switch value logic or operation module (053) outputs 1; The analog value assignment module A (054) is used to set the fixed opening of the valve, and the fixed opening of the valve can be 30% or 100%; The switch quantity switching operation module (055) receives the output value of the RS trigger operation module A (052) and the fixed valve opening set by the analog value assignment module A (054), the output value of the RS trigger operation module A (052) serving as an input control signal of the switch quantity switching operation module (055), and selects the fixed valve opening set by the analog value assignment module A (054) according to the output value of the RS trigger operation module A (052); The RS trigger operation module B (056) receives the output value of the switch logic or operation module (053). If the output value of the switch logic or operation module (053) is 1, the output value of the RS trigger operation module B (056) is 1.

4. A control system for closed-loop continuous regulation of auxiliary water flow according to claim 3, characterized in that: The switch quantity switching operation module (055) outputs a 100% fixed opening if the output value of the RS trigger operation module A (052) is 1, and outputs a 30% fixed opening if the output value of the RS trigger operation module A (052) is 0.

5. A control system for closed-loop continuous regulation of auxiliary water flow according to claim 3, characterized in that: The valve fixed opening operation module (05) further comprises: a soft hand operator operation module A (057) for realizing manual / fixed valve opening control, wherein if manual valve opening control is performed, the T output value in the soft hand operator operation module A (057) is 1, and if fixed valve opening control is performed, the T output value in the soft hand operator operation module A (057) is 0; The RS trigger operation module B (056) receives the output value of the soft hand operator operation module A (057). If the soft hand operator operation module A (057) outputs 1, the RS trigger operation module B (056) outputs a value of 0.

6. A control system for closed-loop continuous regulation of auxiliary water flow according to claim 3, characterized in that: The control system further comprises: a switch quantity switching operation module A (07), receiving the output value of the RS trigger operation module B (056), the output value of the RS trigger operation module B (056) being the input control signal of the switch quantity switching operation module A (07); when the output value of the RS trigger operation module B (056) is 1, the switch quantity switching operation module A (07) receives the output value of the switch quantity switching operation module (055), and outputs the output value of the switch quantity switching operation module (055) to the switch quantity switching operation module B (08); when the output value of the RS trigger operation module B (056) is 0, the switch quantity switching operation module A (07) receives the 100% fixed opening signal of the analog value assignment module A (054); When the output of the switch value logic and operation module (04) is 0, the switch value switching operation module B (08) receives the output value of the switch value switching operation module A (07) to achieve a fixed valve opening.

7. A control system for closed-loop continuous regulation of auxiliary water flow according to claim 5, characterized in that: The control system further comprises: a switch quantity switching operation module C (09) receiving an output value of T in a soft hand operator operation module A (057), the output value of T in the soft hand operator operation module A (057) being used as an input control signal of the switch quantity switching operation module C (09); when the output value of T in the soft hand operator operation module A (057) is 1, the switch quantity switching operation module C (09) selects the output value of A in the soft hand operator operation module A (057), outputs the output value of A in the soft hand operator operation module A (057) to a valve control output module (10), and directly controls the valve opening; when the output value of T in the soft hand operator operation module A (057) is 0, the switch quantity switching operation module C (09) selects the output value of the switch quantity switching operation module B (08), outputs the output value of the switch quantity switching operation module B (08) to the valve control output module (10), and directly controls the valve by the output value of the switch quantity switching operation module B (08).

8. The control system for closed-loop continuous regulation of auxiliary water flow according to claim 1, characterized in that: The valve opening automatic adjustment operation module (06) comprises: an evaporator liquid level measurement module (061), an analog value assignment module B (062), a switch value switching operation module (063), a PID control operation module (064), and a soft hand operator operation module B (065); An evaporator liquid level measurement module (061) is used to measure the evaporator liquid level in real time to obtain an output value of the evaporator liquid level measurement module (061), and transmit the output value to the PID control operation module (064) in real time; Analog value assignment module B (062), used to set the liquid level control of the evaporator liquid level; The soft hand operator operation module B (065) is used to realize manual / continuous valve opening control. If manual valve opening control is performed, the output value of T in the soft hand operator operation module B (065) is 1. If continuous valve opening control is performed, the output value of T in the soft hand operator operation module B (065) is 0. The switch quantity switching operation module (063) receives the output value of T in the soft hand operator operation module B (065), the output value of A in the soft hand operator operation module B (065) and the set value of the analog quantity assignment module B (062); selects the output value of A in the soft hand operator operation module B (065) or the set value of the analog quantity assignment module B (062) according to the output value of T in the soft hand operator operation module B (065), and outputs it to the PID control operation module (064); The PID control operation module (064) compares the output value of the evaporator liquid level measurement module (061) with the output value of the switch value switching operation module (063) in real time, outputs different analog values, and performs real-time continuous control on the valve opening; When the output of the switch value logic and operation module (04) is 1, the switch value switching operation module B (08) receives the output value of the PID control operation module (064) in the valve opening automatic adjustment operation module (06) to realize the automatic adjustment of the valve opening.

9. A control system for closed-loop continuous regulation of auxiliary water flow according to claim 8, characterized in that: The switch quantity switching operation module (063) receives the output value of T in the soft hand operator operation module B (065), and uses the output value of T in the soft hand operator operation module B (065) as an input control signal of the switch quantity switching operation module (063); when the output value of T in the soft hand operator operation module B (065) is 1, the switch quantity switching operation module (063) selects the output value of A in the soft hand operator operation module B (065), and outputs the output value of A in the soft hand operator operation module B (065) to the PID control operation module (064); when the output value of T in the soft hand operator operation module B (065) is 0, the switch quantity switching operation module (063) selects the internal given value of the analog value assignment module B (062), and outputs the internal given value of the analog value assignment module B (062) to the PID control operation module (064).

10. A control system for closed-loop continuous regulation of auxiliary water flow according to claim 8, characterized in that: The PID control operation module (064) compares the output value of the evaporator liquid level measurement module (061) with the output value of the switch quantity switching operation module (063) in real time, and outputs different analog values. Specifically, if the values ​​of the evaporator liquid level measurement module (061) and the switch quantity switching operation module (063) are consistent, the output of the PID control operation module (064) remains unchanged at the current value; if the value of the evaporator liquid level measurement module (061) is greater than the value of the switch quantity switching operation module (063), the output value of the PID control operation module (064) decreases until the values ​​of the evaporator liquid level measurement module (061) and the switch quantity switching operation module (063) are consistent; if the value of the evaporator liquid level measurement module (061) is less than the value of the switch quantity switching operation module (063), the output value of the PID control operation module (064) increases until the values ​​of the evaporator liquid level measurement module (061) and the switch quantity switching operation module (063) are consistent.

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