A method and device for controlling the power of a turbine valve test

Abstract

The application belongs to the technical field of steam turbines, and particularly relates to a steam turbine valve regulating test power control method and device. The method comprises the following steps: obtaining a power set value of a steam turbine in a valve regulating test process and an actual power value of the steam turbine at a current time; determining a deviation between the power set value and the actual power value as a power deviation value; determining a bias value according to the power deviation value; determining a valve regulating opening degree signal according to the bias value, the power deviation value and the power set value; and controlling the opening degree of a non-experimental column valve according to the valve regulating opening degree signal; wherein, in the valve regulating test process, two columns of valves control the steam turbine in parallel, one column of valves is used for valve regulating test, and the other column of valves is the non-experimental column valve. According to the application, the power deviation value is amplified, the input value of a closed loop circuit is increased, and the control effect of a power control system is enhanced.

Description

Technical Field

[0001] This application belongs to the field of steam turbine technology, specifically relating to a steam turbine regulating valve test power control method and device. Background Technology

[0002] Since the beginning of the 21st century, with the rapid development of science and technology, modern society has an ever-increasing demand for electricity. Steam turbine units are one of the core pieces of equipment in power plants, and their operational status and maintenance level have a significant impact on the safe operation of the power plant. Due to the complexity of the steam turbine structure and the special nature of its operating environment, a malfunction can be extremely dangerous, severely affecting the normal operation of the generator unit. The main steam valve and regulating valve, as the most important equipment in the steam turbine, directly affect the safe operation of the power plant's steam turbine system through their reliability and tightness.

[0003] According to relevant standards, in order to properly maintain nuclear power plant steam turbines and enhance their safe operation, there are periodic standard requirements for the activity tests of the main steam valve and main control valve, which are among the important tests for steam turbines. These valve activity tests must be conducted in accordance with the regulations. Therefore, the activity tests of the opening and closing of the main steam valve and control valve of the steam turbine unit are essential.

[0004] To verify the proper functioning of the main steam valve and main control valve of the steam turbine, staff need to conduct regular functional tests to eliminate potential safety hazards caused by jamming of the turbine inlet valves due to long-term operation. Control valve operation tests generally have load requirements for the unit; before conducting these tests, the turbine will reduce its power output to a level suitable for the test based on its own characteristics. For nuclear power units operating stably for extended periods, control valve tests fall within a variable power window. During this period, the operator faces increased monitoring workload, and the variable power affects the stability of the core power distribution, causing fluctuations in nuclear power and continuous control rod movement. The longer a nuclear power unit remains within a variable power window, the more detrimental it is to unit stability and the lower its capacity factor becomes.

[0005] Currently, the existing valve control test system can control the power within a reasonable range under the original valve control test time. However, shortening the valve control test time will lead to a larger power fluctuation range of the steam turbine, which cannot meet the power stability requirements of the steam turbine unit. Summary of the Invention

[0006] The purpose of this application is to provide a power control method and device for turbine valve control tests, which solves the problem in the prior art that shortening the valve control test time will cause excessive power fluctuations in the turbine unit during the turbine valve control test.

[0007] The technical solution to achieve the purpose of this application is as follows: The first aspect of this application provides a method for controlling the test power of a steam turbine regulating valve, the method comprising: Obtain the turbine's power setpoint during the valve control test and the turbine's actual power value at the current moment; The deviation between the power setpoint and the actual power value is determined as the power deviation value; Determine the bias value based on the power deviation value; The valve opening signal is determined based on the bias value, the power deviation value, and the power setting value. The opening degree of the non-experimental train control valve is controlled according to the valve opening degree signal; During the valve control test, two sets of valves control the turbine in parallel. One set of valves is used for the valve control test, while the other set of valves is the non-experimental set of valves.

[0008] Optionally, determining the bias value based on the power deviation value specifically includes: When the power deviation value is greater than the first preset threshold, the first preset value is determined as the bias value; When the power deviation value is less than the second preset threshold, the second preset value is determined as the bias value; When the power deviation value is greater than or equal to the second preset threshold and the power deviation value is less than or equal to the first preset threshold, the bias value is zero; Wherein, the first preset threshold and the first preset value are positive values, and the second preset threshold and the second preset value are negative values.

[0009] Optionally, both the first preset threshold and the first preset value are 3.5; both the second preset threshold and the second preset value are -3.5.

[0010] Optionally, determining the valve opening signal based on the bias value, the power deviation value, and the power setting value specifically includes: PID control is performed based on the bias value and the power deviation value to obtain the differential power request signal; The valve opening signal is determined based on the differential power request signal and the power setting value.

[0011] Optionally, the step of performing PID control based on the bias value and the power deviation value to obtain the differential power request signal specifically includes: The bias value and the power deviation value are used as inputs to the PID controller, and the output of the PID controller is the differential power request signal. The PID controller consists of a proportional unit, an integral unit, and a derivative unit, and its input... With output The relationship is: In the formula, For the accumulation of the PID controller, For the proportional term parameter, The integral time constant is... Let t be the differential time constant, and t be time.

[0012] Optional, =0.25, =12, =0.

[0013] Optionally, determining the valve opening signal based on the differential power request signal and the power setting value specifically includes: The sum of the differential power request signal and the power setting value is obtained to get the desired flow request signal; The valve opening signal is determined based on the expected flow request signal and the preset correspondence between the valve opening and the flow request signal.

[0014] A second aspect of this application provides a test power control device for a steam turbine regulating valve, the device comprising: The first acquisition module is used to acquire the power setpoint of the steam turbine during the valve control test and the actual power value of the steam turbine at the current moment. The first determining module is used to determine the deviation between the power set value and the actual power value, as the power deviation value; The second determining module is used to determine the bias value based on the power deviation value; The third determining module is used to determine the valve opening signal based on the bias value, the power deviation value, and the power setting value; The opening control module is used to control the opening of the non-experimental train control valve according to the valve opening signal; During the valve control test, two sets of valves control the turbine in parallel. One set of valves is used for the valve control test, while the other set of valves is the non-experimental set of valves.

[0015] The third aspect of this application provides a computer scale storage medium storing a computer program, which, when executed, implements any one of the turbine regulating valve test power control methods provided in the first aspect of this application.

[0016] A fourth aspect of this application provides a controller, including a memory and a processor; the memory stores a computer program, which, when executed by the processor, implements any one of the turbine valve control test power control methods provided in the first aspect of this application.

[0017] The beneficial technical effects of this application are as follows: This application provides a power control method and apparatus for a steam turbine valve control test. The method includes: acquiring the power setpoint of the steam turbine during the valve control test and the actual power value of the steam turbine at the current moment; determining the deviation between the power setpoint and the actual power value as a power deviation value; determining an offset value based on the power deviation value; determining a valve opening signal based on the offset value, the power deviation value, and the power setpoint; and controlling the opening of the non-experimental valves based on the valve opening signal. During the valve control test, two valves control the steam turbine in parallel, with one valve undergoing the valve control test and the other being the non-experimental valve. This application amplifies the power deviation value, increasing the input value of the closed-loop circuit and enhancing the control effect of the power control system. Even with a shortened valve control test period, power stability can be guaranteed, and the power fluctuation amplitude during the valve control test is reduced to a smaller value than the original power fluctuation amplitude, thus improving the safety of steam turbine operation. Attached Figure Description

[0018] Figure 1 A schematic flowchart illustrating a test power control method for a steam turbine regulating valve, provided as an embodiment of this application; Figure 2 A schematic diagram of the control principle of a turbine regulating valve test power control method provided in this application embodiment; Figure 3 A power comparison diagram between a turbine regulating valve test power control method provided in this application embodiment and the original control method; Figure 4 The power response curve of a turbine valve control test power control method provided in this application under the condition of shortening the valve control test time; Figure 5 The bias response curve of a turbine valve control test power control method provided in this application under the condition of shortening the valve control test time. Detailed Implementation

[0019] To enable those skilled in the art to better understand this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only a part of the embodiments of this application, and not all of them. Based on the embodiments described in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] See Figure 1 The figure is a schematic flowchart of a turbine regulating valve test power control method provided in an embodiment of this application.

[0021] This application provides a method for controlling the test power of a steam turbine regulating valve, comprising: Step S101: Obtain the turbine's power setpoint and the turbine's actual power value at the current moment during the valve control test; In practice, the power setpoint and the actual power value can be normalized to obtain a relative power value for subsequent control.

[0022] Step S102: Determine the deviation between the power setting value and the actual power value, and use it as the power deviation value; Step S103: Determine the bias value based on the power deviation value; Step S104: Determine the valve opening signal based on the bias value, the power deviation value, and the power setting value; Step S105: Control the opening degree of the non-experimental train control valve according to the control valve opening degree signal; During the valve control test, two sets of valves control the turbine in parallel. One set of valves is used for the valve control test, while the other set of valves is the non-experimental set of valves.

[0023] It is understood that by amplifying the power deviation value in this application embodiment, the input value of the closed loop is increased, thereby enhancing the control effect of the power control system. Even when the turbine valve control test is shortened, the power stability can still be guaranteed. The power fluctuation amplitude during the valve control test is smaller than the original power fluctuation amplitude, which can improve the safety of turbine operation.

[0024] In some possible implementations of the embodiments of this application, step S103 may specifically include: When the power deviation value is greater than the first preset threshold, the first preset value is determined as the bias value; When the power deviation value is less than the second preset threshold, the second preset value is determined as the bias value; When the power deviation value is greater than or equal to the second preset threshold and the power deviation value is less than or equal to the first preset threshold, the bias value is zero; Wherein, the first preset threshold and the first preset value are positive values, and the second preset threshold and the second preset value are negative values.

[0025] In one example, the first preset threshold and the first preset value can both be 3.5; the second preset threshold and the second preset value can both be -3.5.

[0026] As an example, when the deviation between the relative power setting and the current relative power is greater than 3.5, the bias circuit outputs a bias value of 3.5 until the power deviation is less than or equal to -2, at which point the bias circuit outputs a value of 0; when the deviation between the power setting and the current power is less than -3.5, the bias circuit outputs a negative bias value of -3.5 until the power deviation is greater than or equal to 2 / 7, at which point the bias circuit outputs a value of 0.

[0027] In some possible implementations of the embodiments of this application, step S104 may specifically include: PID control is performed based on the bias value and the power deviation value to obtain the differential power request signal; The valve opening signal is determined based on the differential power request signal and the power setting value.

[0028] In one example, the step of performing PID control based on the bias value and the power deviation value to obtain the differential power request signal specifically includes: The bias value and the power deviation value are used as inputs to the PID controller, and the output of the PID controller is the differential power request signal. The PID controller consists of a proportional unit, an integral unit, and a derivative unit, and its input... With output The relationship is: In the formula, For the accumulation of the PID controller, For the proportional term parameter, The integral time constant is... Let t be the differential time constant, and t be time.

[0029] As an example, =0.25, =12, =0.

[0030] In another example, determining the valve opening signal based on the differential power request signal and the power setpoint specifically includes: The sum of the differential power request signal and the power setting value is obtained to get the desired flow request signal; The valve opening signal is determined based on the expected flow request signal and the preset correspondence between the valve opening and the flow request signal.

[0031] For example, the correspondence between valve opening degree and flow request signal can be: Valve opening =[0 0.1 8 31 38 48 63 99]; Traffic request signal =[0 0.4 6 72 85.5 95 98 100].

[0032] Figure 2 An example illustrates the control principle of a turbine valve control test power control method provided in an embodiment of this application. The system includes a preprocessing module for preprocessing the power setpoint and actual value; a subtractor for subtracting the power setpoint and actual value; a bias loop for adjusting the power deviation value through an output bias value; a PID controller for calculating a flow request signal based on the sum of the deviation value output by the subtractor and the bias value output by the bias loop; a valve control test controller module (non-test series) for calculating the flow request rate based on the flow request signal, or a manually set flow request rate module (test series); a converter for converting the flow request rate signal into a corresponding valve opening signal; a main control valve as the actuator; and a turbine as the controlled object.

[0033] The main control valve is divided into two columns, A and B: Column A contains controller 1 (or a manually set module), converter 1, and main control valve 1; Column B contains controller 2 (or a manually set module), converter 2, and main control valve 2. The subtractor output is connected to the bias loop input. The sum of the bias loop output and the subtractor output is connected to the PID controller input. The sum of the PID controller output and the pre-processed power setpoint is connected to the control valve test controller input. The control valve test controller output is connected to the converter input, and the converter output is connected to the main control valve. The main control valve is connected to the turbine. During the control valve test, the output of the control valve test controller in the test column is the manually set rate of change of the requested flow rate during the test, independent of the control valve test controller input. The output of the controllers in the non-test columns is equal to the input. Furthermore, after the control valve test begins, the test column and the non-test column are switched when the valve openings of the two columns reach consistency for the first time. The control valve test ends when the valve openings of the two columns reach consistency for the second time.

[0034] The power control method for valve control tests based on bias loop optimization in this application amplifies the power deviation value through the bias loop, thereby increasing the input value of the closed-loop PID and enhancing the control effect of the power control system. It can simulate the power change trend of the turbine unit under different flow request rates during the valve control test, and has a certain degree of scalability. Through simulation under different flow request rate settings, it can help the staff to better control the working performance of the turbine unit.

[0035] The advantages and positive effects of the embodiments of this application are as follows: (1) The power control method based on bias loop optimization closed-loop feedback control amplifies the power deviation value through the bias loop, which increases the input value of the PID of the closed-loop loop, enhances the control effect of the valve adjustment test, and enables the turbine unit to ensure power stability while shortening the valve adjustment test. (2) From the perspective of safety, the bias loop optimization closed-loop feedback control will reduce the power fluctuation amplitude during the valve control test to less than the original power fluctuation amplitude, which can improve the safety of turbine unit operation. (3) The structure is simple. It only requires biasing the power deviation signal. The biasing circuit will not affect the overall integrity of the original control system. The biasing circuit can be set to be engaged and disengaged by the user. It is easy to operate and flexible to use. (4) The turbine control method based on bias loop optimization is applicable not only to the turbine power control during the valve control test, but also to the turbine power control of other turbines during the variable power window, and has a certain degree of versatility. (4) After optimizing the test time characteristics of the regulating valve, the time required for a large number of professional personnel to provide support can be reduced, and the operation time and monitoring burden of the operators can be reduced. (5) From an economic perspective, shortening the valve adjustment test time reduces the time the unit spends on the low-power platform, thus improving the unit's capacity factor.

[0036] The following is a detailed explanation of a turbine control valve test power control method provided in this application, using a specific example.

[0037] The valve control test data is the actual data from a steam turbine unit's winter valve control test. The valve control test conditions are simulated using a simulation platform to simulate the power fluctuations of the steam turbine unit during the valve control test. The power fluctuations are optimized using a steam turbine valve control test power control method provided in this application embodiment.

[0038] Please see Figure 3 To compare the power of the control method in this application with the original control method under the valve control test condition where the flow request rate changes at a rate of 0.033% / s, it can be seen that the maximum power fluctuation of the original scheme is 8.09 MW during the entire valve control test, while the maximum power fluctuation of this application is 4.2369 MW. Compared with the original scheme, the maximum power fluctuation of this application is reduced by 47.6%, indicating that this application has a better control effect on power fluctuation during the valve control test.

[0039] Please see Figure 4 and Figure 5 , Figure 4The power response curve of the control method in this application is obtained under the valve control test condition where the flow request rate changes at a rate of 0.08% / s. When the flow request rate changes by a factor of two, i.e., the valve control test time is halved, the maximum power fluctuation is 4.7522 MW, which is lower than the maximum power fluctuation of the original control scheme under the valve control test condition where the flow request rate changes at a rate of 0.033% / s. Figure 5 The bias response curve of the control method in this application is shown under the valve control test condition where the flow request rate changes at a rate of 0.08% / s. It can be seen that during the entire valve control test, the bias loop has a positive output bias for 1214.3 s and a negative output bias for 784.2 s. This indicates that the valve control test power control method based on bias loop optimized closed-loop feedback control can solve the problem of excessive power fluctuations in the turbine unit caused by shortening the turbine valve control test time.

[0040] In summary, the power control system and method for valve adjustment tests based on bias loop optimized closed-loop feedback control in this application, through comparison with real data from a steam turbine unit's winter valve adjustment test, verifies that this application has a superior steam turbine power control effect and solves the problem of excessive power fluctuations in the steam turbine unit caused by shortening the steam turbine valve adjustment test time.

[0041] Based on the turbine valve control test power control method provided in the above embodiments, this application also provides a turbine valve control test power control device.

[0042] This application provides an embodiment of a steam turbine regulating valve test power control device, comprising: The first acquisition module is used to acquire the power setpoint of the steam turbine during the valve control test and the actual power value of the steam turbine at the current moment. The first determining module is used to determine the deviation between the power set value and the actual power value, as the power deviation value; The second determining module is used to determine the bias value based on the power deviation value; The third determining module is used to determine the valve opening signal based on the bias value, the power deviation value, and the power setting value; The opening control module is used to control the opening of the non-experimental train control valve according to the valve opening signal; During the valve control test, two sets of valves control the turbine in parallel. One set of valves is used for the valve control test, while the other set of valves is the non-experimental set of valves.

[0043] In some possible implementations of the embodiments of this application, the second determining module may specifically be used for: When the power deviation value is greater than the first preset threshold, the first preset value is determined as the bias value; When the power deviation value is less than the second preset threshold, the second preset value is determined as the bias value; When the power deviation value is greater than or equal to the second preset threshold and the power deviation value is less than or equal to the first preset threshold, the bias value is zero; Wherein, the first preset threshold and the first preset value are positive values, and the second preset threshold and the second preset value are negative values.

[0044] In one example, the first preset threshold and the first preset value can both be 3.5; the second preset threshold and the second preset value can both be -3.5.

[0045] In some possible implementations of the embodiments of this application, the third determining module may specifically be used for: PID control is performed based on the bias value and the power deviation value to obtain the differential power request signal; The valve opening signal is determined based on the differential power request signal and the power setting value.

[0046] In one example, the step of performing PID control based on the bias value and the power deviation value to obtain the differential power request signal specifically includes: The bias value and the power deviation value are used as inputs to the PID controller, and the output of the PID controller is the differential power request signal. The PID controller consists of a proportional unit, an integral unit, and a derivative unit, and its input... With output The relationship is: In the formula, For the accumulation of the PID controller, For the proportional term parameter, The integral time constant is... Let t be the differential time constant, and t be time.

[0047] As an example, =0.25, =12, =0.

[0048] In another example, determining the valve opening signal based on the differential power request signal and the power setpoint specifically includes: The sum of the differential power request signal and the power setting value is obtained to get the desired flow request signal; The valve opening signal is determined based on the expected flow request signal and the preset correspondence between the valve opening and the flow request signal.

[0049] This application embodiment amplifies the power deviation value, thereby increasing the input value of the closed-loop circuit and enhancing the control effect of the power control system. It can also ensure power stability even when the turbine's valve control test is shortened, and reduce the power fluctuation amplitude during the valve control test to be smaller than the original power fluctuation amplitude, thus improving the safety of turbine operation.

[0050] Based on the turbine regulating valve test power control method and apparatus provided in the above embodiments, this application also provides a computer scale storage medium, characterized in that it stores a computer program, and when the computer program is executed, it implements any one of the turbine regulating valve test power control methods provided in the above embodiments.

[0051] Based on the turbine valve control test power control method and apparatus provided in the above embodiments, this application also provides a controller, including a memory and a processor; the memory stores a computer program, and when the computer program is executed by the processor, it implements any one of the turbine valve control test power control methods provided in the above embodiments.

[0052] The present application has been described in detail above with reference to the accompanying drawings and embodiments. However, the present application is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present application. All content not described in detail in this application can be derived from existing technology.

Claims

1. A method for controlling the test power of a steam turbine regulating valve, characterized in that, The method includes: Obtain the turbine's power setpoint during the valve control test and the turbine's actual power value at the current moment; The deviation between the power setpoint and the actual power value is determined as the power deviation value; Determine the bias value based on the power deviation value; The valve opening signal is determined based on the bias value, the power deviation value, and the power setting value. The opening degree of the non-experimental train control valve is controlled according to the valve opening degree signal; During the valve control test, two sets of valves control the turbine in parallel. One set of valves is used for the valve control test, while the other set of valves is the non-experimental set of valves.

2. The turbine regulating valve test power control method according to claim 1, characterized in that, The step of determining the bias value based on the power deviation value specifically includes: When the power deviation value is greater than the first preset threshold, the first preset value is determined as the bias value; When the power deviation value is less than the second preset threshold, the second preset value is determined as the bias value; When the power deviation value is greater than or equal to the second preset threshold and the power deviation value is less than or equal to the first preset threshold, the bias value is zero; Wherein, the first preset threshold and the first preset value are positive values, and the second preset threshold and the second preset value are negative values.

3. The turbine regulating valve test power control method according to claim 2, characterized in that, The first preset threshold and the first preset value are both 3.5; the second preset threshold and the second preset value are both -3.

5.

4. The turbine regulating valve test power control method according to any one of claims 1-3, characterized in that, The step of determining the valve opening signal based on the bias value, the power deviation value, and the power setting value specifically includes: PID control is performed based on the bias value and the power deviation value to obtain the differential power request signal; The valve opening signal is determined based on the differential power request signal and the power setting value.

5. The turbine regulating valve test power control method according to claim 4, characterized in that, The step of performing PID control based on the bias value and the power deviation value to obtain the differential power request signal specifically includes: The bias value and the power deviation value are used as inputs to the PID controller, and the output of the PID controller is the differential power request signal. The PID controller consists of a proportional unit, an integral unit, and a derivative unit, and its input... With output The relationship is: In the formula, For the accumulation of the PID controller, For the proportional term parameter, The integral time constant is... Let t be the differential time constant, and t be time.

6. The turbine regulating valve test power control method according to claim 5, characterized in that, =0.25， =12， =0。 7. The turbine regulating valve test power control method according to claim 4, characterized in that, The step of determining the valve opening signal based on the differential power request signal and the power setting value specifically includes: The sum of the differential power request signal and the power setting value is obtained to get the desired flow request signal; The valve opening signal is determined based on the expected flow request signal and the preset correspondence between the valve opening and the flow request signal.

8. A test power control device for a steam turbine regulating valve, characterized in that, The device includes: The first acquisition module is used to acquire the power setpoint of the steam turbine during the valve control test and the actual power value of the steam turbine at the current moment. The first determining module is used to determine the deviation between the power set value and the actual power value, as the power deviation value; The second determining module is used to determine the bias value based on the power deviation value; The third determining module is used to determine the valve opening signal based on the bias value, the power deviation value, and the power setting value; The opening control module is used to control the opening of the non-experimental train control valve according to the valve opening signal; During the valve control test, two sets of valves control the turbine in parallel. One set of valves is used for the valve control test, while the other set of valves is the non-experimental set of valves.

9. A computer-calibrated storage medium, characterized in that, It stores a computer program, which, when executed, implements the turbine regulating valve test power control method as described in any one of claims 1-7.

10. A controller, characterized in that, It includes a memory and a processor; the memory stores a computer program, which, when executed by the processor, implements the turbine valve control test power control method as described in any one of claims 1-7.

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