Overflow valve control system for BEST small steam turbine

Abstract

The present application proposes a relief valve regulating control system for BEST small steam turbines, which includes: an analog handheld operator unit, an automatic command output unit, an emergency state identification unit, a tracking state identification unit, an automatic state identification unit, and an analog signal output unit for the valve position instruction of the BEST small steam turbine relief valve. The system can be fully applicable to BEST small steam turbine equipment with a small generator, which can not only automatically adjust the relief valve according to different working conditions to avoid accidents and ensure the safe and stable operation of the BEST small steam turbine, but also achieve the goal of reducing staff and increasing efficiency.

Description

Technical Field

[0001] The present application relates to the field of intelligent control of a BEST small steam turbine with a small generator of an ultra-supercritical secondary reheat coal-fired unit, and in particular to a relief valve regulating and controlling system applied to a BEST small steam turbine. Background Art

[0002] BEST small steam turbine with small generator has the advantages of high efficiency and energy saving, and has been successfully applied in the actual production of thermal power plants. When the BEST small steam turbine is started and operated normally, when the bypass valve of the BEST small steam turbine is fully opened, the No. 7 low-pressure heater is cut off, the No. 8 low-pressure heater is cut off, the BEST small steam turbine trips, and the bypass valve opens quickly, if the overflow valve fails to regulate and control, it will cause the pressure of the BEST small steam turbine to be unbalanced, the system cannot unload and endanger the safety protection, which seriously affects the stable and safe operation of the BEST small steam turbine.

[0003] Therefore, considering the unique operating characteristics of the BEST small steam turbine with a small generator, designing a relief valve regulation and control system for the BEST small steam turbine has become an urgent problem to be solved. Summary of the invention

[0004] In order to solve the above problems, the present application provides a relief valve regulating control system applied to a BEST small steam turbine.

[0005] According to one aspect of the present application, a relief valve regulating control system applied to a BEST small steam turbine is provided, comprising:

[0006] The analog hand operator unit is used to output the valve position command of the BEST small steam turbine overflow valve according to the input data of each input terminal;

[0007] An automatic command output unit, used for outputting a valve position command when the relief valve is in an automatic operation state according to a back pressure setting value and a final stage pressure ratio setting value of the BEST small steam turbine; the automatic command output unit is connected to the X input terminal of the analog quantity hand operator unit;

[0008] An emergency state identification unit is used to output a signal indicating whether the BEST small steam turbine is in an emergency state according to the operating state of the BEST small steam turbine; the output end of the emergency state identification unit is connected to the ToM input end of the analog hand operator unit;

[0009] A tracking state recognition unit, used for outputting a signal indicating whether the relief valve is in a tracking state according to an output signal of the emergency state recognition unit; an input end of the tracking state recognition unit is connected to an output end of the emergency state recognition unit, and an output end of the tracking state recognition unit is connected to a TS input end of the analog hand operator unit;

[0010] An automatic state recognition unit, used for outputting a signal indicating whether the relief valve is in an automatic operation state according to the output signal of the emergency state recognition unit, the sequential control start-up progress of the BEST small steam turbine and the bypass valve state; the input end of the automatic state recognition unit is connected to the output end of the emergency state recognition unit, and the output end of the automatic state recognition unit is connected to the ReqA input end of the analog quantity hand operator unit;

[0011] The analog signal output unit of the valve position instruction of the BEST small steam turbine overflow valve is connected to the signal output end of the analog hand operator unit.

[0012] In some embodiments of the present application, the automatic instruction output unit includes an analog signal input module for the BEST small steam turbine back pressure setting value, an analog signal input module for the BEST small steam turbine final stage pressure ratio setting value, and a maximum value selection module; wherein:

[0013] The analog signal input module of the BEST small steam turbine back pressure setting value and the analog signal input module of the BEST small steam turbine final stage pressure ratio setting value are both connected to the input end of the maximum value selection module, and the output end of the maximum value selection module is connected to the X input end of the analog quantity handheld operator unit.

[0014] In some embodiments of the present application, the emergency state identification unit includes a switch signal input module for BEST small steam turbine tripping, a switch signal input module for bypass valve quick opening solenoid valve energized instruction, a first switch signal input module for BEST small steam turbine bypass valve full closure, a switch signal input module for cutting off the No. 7 low-pressure heater, a switch signal input module for cutting off the No. 8 low-pressure heater, a first or module, a first not module and a first and module; wherein:

[0015] The first switch signal input module of the fully closed bypass valve of the BEST small steam turbine is connected to the input end of the first non-module;

[0016] The switch quantity signal input module for the removal of the No. 7 low-pressure heater and the switch quantity signal input module for the removal of the No. 8 low-pressure heater are both connected to the input end of the first module;

[0017] The switch signal input module for the BEST small steam turbine tripping, the switch signal input module for the bypass valve quick opening solenoid valve energized instruction, the output end of the first non-module, the output end of the first and module, and the switch signal input module for the No. 8 low-pressure heater cutoff are all connected to the input end of the first or module.

[0018] In some embodiments of the present application, the tracking state identification unit includes a pulse module, the input end of the pulse module is connected to the output end of the emergency state identification unit, and the output end of the pulse module is connected to the TS input end of the analog hand operator unit.

[0019] In some embodiments of the present application, the automatic state identification unit includes a switch signal input module for the instruction of the twentieth step of the BEST small steam turbine startup sequence control, a second switch signal input module for the fully closed bypass valve of the BEST small steam turbine, a switch signal input module for the manual mode of the bypass valve position control, a second NOT module, a second AND module, a second OR module and a third AND module; wherein:

[0020] The input end of the second non-module is connected to the output end of the emergency state identification unit;

[0021] The second switch signal input module of the bypass valve of the BEST small steam turbine fully closed and the switch signal input module of the bypass valve position control manual mode are both connected to the input end of the second AND module; the switch signal input module of the instruction of the 20th step of the BEST small steam turbine startup sequence control and the output end of the second AND module are both connected to the input end of the second OR module;

[0022] The output end of the second NOT module and the output end of the second OR module are both connected to the input end of the third AND module, and the output end of the third AND module is connected to the ReqA input end of the analog quantity hand operator unit.

[0023] In addition, the automatic state recognition unit also includes a delayed shutdown module; wherein:

[0024] The switch signal input module of the instruction of the twentieth step of the BEST small steam turbine startup sequence control is connected to the input end of the delayed closing module, and the output end of the delayed closing module and the output end of the second and module are both connected to the input end of the second or module.

[0025] In some embodiments of the present application, the system further comprises:

[0026] A first constant unit connected to the TR input terminal of the analog hand operator unit, wherein the preset value in the first constant unit is 0.

[0027] In addition, the system comprises:

[0028] A second constant unit is used to set a high limit value of the output of the analog hand operator unit; the second constant unit is connected to the MaxOut input terminal of the analog hand operator unit;

[0029] The third constant unit is used to set the lower limit value of the output of the analog hand operator unit; the third constant unit is connected to the MinOut input terminal of the analog hand operator unit.

[0030] According to the technical solution of the present application, the automatic state recognition unit, the tracking state recognition unit and the emergency state recognition unit are used to determine the control state of the BEST small steam turbine overflow valve in combination with different working conditions, and the analog hand operator unit outputs the corresponding valve position instruction of the BEST small steam turbine overflow valve according to the control state of the overflow valve to adjust the valve position of the bypass valve in real time. The system can be fully applicable to equipment with a BEST small steam turbine and a small generator, and can not only automatically adjust the overflow valve according to different working conditions to avoid accidents and ensure the safe and stable operation of the BEST small steam turbine, but also achieve the goal of reducing staff and increasing efficiency.

[0031] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0033] Figure 1 This is a structural block diagram of the BEST small steam turbine with generator in the embodiment of the present application;

[0034] Figure 2 A structural block diagram of a relief valve regulating control system applied to a BEST small steam turbine provided in an embodiment of the present application;

[0035] Figure 3 A structural block diagram of another overflow valve regulating control system applied to a BEST small steam turbine provided in an embodiment of the present application;

[0036] Figure 4 A schematic diagram of the corresponding relationship between the load and the back pressure setting value of the BEST small steam turbine in the embodiment of the present application;

[0037] Figure 5 It is a schematic diagram of the corresponding relationship between the actual rotation speed of the BEST small steam turbine and the set value of the final stage pressure ratio in the embodiment of the present application.

[0038] Reference numerals:

[0039] BEST small steam turbine, 101; generator, 102; converter, 103; No. 1 main steam valve, V01; No. 2 main steam valve, V02; No. 1 main steam regulating valve, V03; No. 2 main steam regulating valve, V04; No. 7 extraction check valve, V05; No. 7 extraction steam electric valve, V06; overflow valve pipeline stop valve, V07; bypass valve, V08; steam supplement valve, V09; overflow valve, V10. DETAILED DESCRIPTION

[0040] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0041] It should be noted that the BEST small steam turbine with small generator has the advantages of high efficiency and energy saving, and has been successfully applied in the actual production of thermal power plants. When the BEST small steam turbine is started and operated normally, when the bypass valve of the BEST small steam turbine is fully opened, the No. 7 low-pressure heater is cut off, the No. 8 low-pressure heater is cut off, the BEST small steam turbine trips, and the bypass valve opens quickly, if the overflow valve fails to regulate and control, it will cause the pressure stabilization of the BEST small steam turbine to be unbalanced, the system cannot unload and endanger safety protection, which seriously affects the stable and safe operation of the BEST small steam turbine.

[0042] Therefore, considering the unique operating characteristics of the BEST small steam turbine with a small generator, designing a relief valve regulation and control system for the BEST small steam turbine has become an urgent problem to be solved.

[0043] In order to solve the above problems, the present application provides a bypass valve regulation and control system based on a BEST small steam turbine.

[0044] It should be noted that if Figure 1As shown, the BEST small steam turbine 101 is connected to the generator 102 through a transmission shaft, the generator 102 is connected to the converter 103, and the BEST small steam turbine 101 is connected to the steam source through two steam input pipelines, one of which is equipped with a No. 1 main steam valve V01 and a No. 1 main steam regulating valve V03, and the other steam input pipeline is equipped with a No. 2 main steam valve V02 and a No. 2 main steam regulating valve V04. The No. 7 extraction steam outlet of the BEST small steam turbine 101 is connected to the No. 7 extraction check valve V05, the No. 7 extraction steam electric valve V06 and the exhaust steam header 104 in sequence through pipelines. The exhaust steam header 104 is connected to the steam source, the condenser, the No. 8 low-pressure heater and the No. 7 low-pressure heater through pipelines respectively. The pipeline between the exhaust steam header 104 and the No. 8 low-pressure heater is connected with the overflow valve pipeline stop valve V07 and the overflow valve V10. The pipeline between the exhaust steam header 104 and the condenser is connected with the bypass valve V08. The pipeline between the exhaust steam header 104 and the steam source is connected with the supplementary steam valve V09.

[0045] Figure 2 This is a structural block diagram of a relief valve regulating control system for a BEST small steam turbine provided in an embodiment of the present application. Figure 2 As shown, the system includes: an analog quantity hand operator unit 201, an automatic instruction output unit 202, an emergency state identification unit 203, a tracking state identification unit 204, an automatic state identification unit 205 and an analog quantity signal output unit 206 for the valve position instruction of the BEST small steam turbine overflow valve.

[0046] In some embodiments of the present application, the analog hand operator unit 201 is used to output the valve position instruction of the BEST small steam turbine overflow valve according to the input data of each input terminal. The automatic instruction output unit 202 is used to output the valve position instruction when the overflow valve is in the automatic operation state according to the back pressure setting value and the final stage pressure ratio setting value of the BEST small steam turbine. The automatic instruction output unit 202 is connected to the X input terminal of the analog hand operator unit 201.

[0047] The emergency state identification unit 203 is used to output a signal indicating whether the BEST small steam turbine is in an emergency state according to the operating state of the BEST small steam turbine. The output end of the emergency state identification unit 203 is connected to the ToM input end of the analog hand operator unit 201. The ToM input end of the analog hand operator unit 201 is a switch for switching the manual state. If the BEST small steam turbine is in an emergency state, the switch signal received by the ToM input end is 1, indicating that the overflow valve needs to be switched to manual control. In this case, the operating personnel can adjust the valve position of the BEST small steam turbine overflow valve by themselves. If the BEST small steam turbine is not in an emergency state, the switch signal received by the ToM input end is 0, indicating that the overflow valve does not need to be switched to manual control, so the analog hand operator unit 201 is not in manual control state.

[0048] The tracking state identification unit 204 is used to output a signal indicating whether the overflow valve is in the tracking state according to the output signal of the emergency state identification unit. The input end of the tracking state identification unit 204 is connected to the output end of the emergency state identification unit 203, and the output end of the tracking state identification unit 204 is connected to the TS input end of the analog hand operator unit 201. The TS input end of the analog hand operator unit 201 is a switching switch of the tracking state. If the switch signal received at the TS input end is 1, the overflow valve is in the tracking state, and the analog hand operator unit 201 outputs the tracking value of the TR input end as the valve position instruction. If the switch signal received at the TS input end is 0, it means that the overflow valve is not in the tracking state, and the tracking value of the TR input end of the analog hand operator unit 201 is not triggered.

[0049] Among them, the tracking value of the TR input end of the analog hand operator unit 201 can be set to 0. If the emergency state identification unit 203 outputs the switch signal 1, the tracking state identification unit 204 can output a signal that the overflow valve is in the tracking state within a preset time period, that is, the tracking state identification unit 204 outputs the switch signal 1 within the preset time period, so the analog hand operator unit 201 outputs the tracking value 0, and the analog signal output unit 206 of the valve position instruction of the BEST small steam turbine overflow valve controls the overflow valve to close. At the same time, since the output end of the emergency state identification unit 203 is connected to the ToM input end of the analog hand operator unit 201, if the emergency state identification unit 203 outputs the switch signal 1, the analog hand operator unit 201 first triggers the tracking state, outputs the valve position instruction of the overflow valve closing, and after receiving the switch signal 0 at the TS input end, if the switch signal output by the emergency state identification unit 203 is still 1, the manual control state is switched.

[0050] The automatic state identification unit 205 is used to output a signal indicating whether the overflow valve is in the automatic operation state according to the output signal of the emergency state identification unit 203, the sequential control start-up progress of the BEST small steam turbine and the bypass valve state. The input end of the automatic state identification unit 205 is connected to the output end of the emergency state identification unit 203, and the output end of the automatic state identification unit 205 is connected to the ReqA input end of the analog quantity hand operator unit 201. The analog quantity signal output unit 206 of the valve position instruction of the BEST small steam turbine overflow valve is connected to the signal output end of the analog quantity hand operator unit 201. After receiving the valve position instruction, the analog quantity signal output unit 206 of the valve position instruction of the BEST small steam turbine overflow valve controls the overflow valve.

[0051] In some embodiments of the present application, the ReqA input terminal of the analog hand operator unit 201 is a switch for switching the automatic operation state. If the switch signal received by the ReqA input terminal of the analog hand operator unit 201 is 1, that is, the relief valve is in the automatic operation state, the analog hand operator unit 201 uses the received value of the X input terminal as the output relief valve position instruction. If the switch signal received by the ReqA input terminal of the analog hand operator unit 201 is 0, that is, the relief valve is not in the automatic operation state, the manual operation state of the analog hand operator unit 201 is not triggered.

[0052] like Figure 2 As shown, the system may further include a first constant unit 207, a second constant unit 208 and a third constant unit 209. The first constant unit 207 is connected to the TR input terminal of the analog hand operator unit 201, and the preset value in the first constant unit 207 is 0. The second constant unit 208 is used to set the high limit value output by the analog hand operator unit 201. The second constant unit 208 is connected to the MaxOut input terminal of the analog hand operator unit 201. The third constant unit 209 is used to set the low limit value output by the analog hand operator unit 201, and the third constant unit 209 is connected to the MinOut input terminal of the analog hand operator unit 201. For example, the preset value in the second constant unit 208 may be 100, and the preset value in the third constant unit 209 may be 0.

[0053] In some embodiments of the present application, Figure 3 As shown, the automatic command output unit 202 includes an analog signal input module 301 for the BEST small steam turbine back pressure setting value, an analog signal input module 302 for the BEST small steam turbine final stage pressure ratio setting value, and a large value selection module 311. Among them: the analog signal input module 301 for the BEST small steam turbine back pressure setting value and the analog signal input module 302 for the BEST small steam turbine final stage pressure ratio setting value are both connected to the input end of the large value selection module 311, and the output end of the large value selection module 311 is connected to the X input end of the analog quantity hand operator unit 201.

[0054] The analog signal input module 301 of the BEST small steam turbine back pressure setting value is used to determine the back pressure setting value according to the unit load based on the corresponding relationship between the load and the back pressure setting value. As an example, Figure 5 The schematic diagram of the corresponding relationship between the BEST small steam turbine load and the back pressure setting value in the embodiment of the present application, the analog signal input module 301 of the BEST small steam turbine back pressure setting value is as follows Figure 4The corresponding relationship shown is used to determine the corresponding back pressure setting value according to the unit load. The analog signal input module 302 of the BEST small steam turbine final stage pressure ratio setting value is used to determine the final stage pressure ratio setting value according to the actual speed of the BEST small steam turbine. Figure 5 The schematic diagram of the corresponding relationship between the actual speed of the BEST small steam turbine and the final stage pressure ratio setting value is shown in FIG. 3 . The analog signal input module 302 of the final stage pressure ratio setting value of the BEST small steam turbine is based on Figure 5 The corresponding relationship shown is used to determine the final stage pressure ratio setting value Y based on the actual speed X of the BEST small steam turbine.

[0055] That is, the large value selection module 311 compares the received back pressure setting value and the final stage pressure ratio setting value of the BEST small steam turbine, and inputs the larger value of the two as the output value to the X input terminal of the analog hand operator unit 201.

[0056] In some embodiments of the present application, Figure 3 As shown, the emergency state identification unit 203 includes a switch signal input module 303 for the tripping of the BEST small steam turbine, a switch signal input module 304 for the energized instruction of the bypass valve quick opening solenoid valve, a first switch signal input module 305 for the full closing of the BEST small steam turbine bypass valve, a switch signal input module 306 for the removal of the No. 7 low-pressure heater, a switch signal input module 307 for the removal of the No. 8 low-pressure heater, a first OR module 312, a first NOT module 315 and a first AND module 317.

[0057] Among them, the first switch signal input module 305 of the bypass valve of the BEST small steam turbine is fully closed and connected to the input end of the first non-module 315. The switch signal input module 306 of the cut-off of the No. 7 low-pressure heater and the switch signal input module 307 of the cut-off of the No. 8 low-pressure heater are both connected to the input end of the first and module 317. The switch signal input module 303 of the tripping of the BEST small steam turbine, the switch signal input module 304 of the energized instruction of the bypass valve quick opening solenoid valve, the output end of the first non-module 315, the output end of the first and module 317 and the switch signal input module 307 of the cut-off of the No. 8 low-pressure heater are all connected to the input end of the first or module 312.

[0058] That is to say, when the operating conditions of the BEST small steam turbine meet the BEST small steam turbine tripping, or the bypass valve opens quickly, or the bypass valve is fully open, or the No. 8 low-pressure heater is cut off, or the No. 7 low-pressure heater is cut off and the No. 8 low-pressure heater is cut off, the emergency state identification unit 203 outputs a high-level signal, otherwise the emergency state identification unit 203 outputs a low-level signal.

[0059] like Figure 3As shown, the tracking state identification unit 204 includes a pulse module 314, the input end of the pulse module 314 is connected to the output end of the emergency state identification unit 203, and the output end of the pulse module 314 is connected to the TS input end of the analog hand operator unit 201. Wherein, a pulse time is set in the pulse module 314. If the switch signal output by the emergency state identification unit 203 is 1, the switch signal output by the pulse module 314 within the pulse time is 1, that is, the tracking state is triggered within the pulse time, and the valve position instruction output by the analog hand operator unit 201 within the pulse time is the tracking value, that is, the valve position instruction for closing the overflow valve. Since the output end of the emergency state identification unit 203 is connected to the ToM input end of the analog hand operator unit 201, if the switch signal output by the emergency state identification unit 203 is 1, the tracking state is first triggered within the pulse time, that is, the overflow valve is first closed, and it is switched to the manual control state after the pulse time.

[0060] That is to say, when the operating conditions of the BEST small steam turbine meet the BEST small steam turbine tripping, or the bypass valve opens quickly, or the bypass valve is fully open, or the No. 8 low-pressure heater is cut off, or the No. 7 low-pressure heater is cut off and the No. 8 low-pressure heater is cut off, the system can automatically adjust the BEST small steam turbine overflow valve to manual mode, and immediately put the BEST small steam turbine overflow valve in the fully closed state.

[0061] In some embodiments of the present application, the automatic state identification unit 205 includes a switch signal input module 308 for the instruction of the 20th step of the BEST small steam turbine startup sequence control, a second switch signal input module 309 for the BEST small steam turbine bypass valve to be fully closed, a switch signal input module 310 for the bypass valve position control manual mode, a second negation module 316, a second and module 318, a second or module 313, and a third and module 319. Among them, the input end of the second negation module 316 is connected to the output end of the emergency state identification unit 203. The second switch signal input module 309 for the BEST small steam turbine bypass valve to be fully closed and the switch signal input module 310 for the bypass valve position control manual mode are both connected to the input end of the second and module 318. The output ends of the switch signal input module 308 for the instruction of the 20th step of the BEST small steam turbine startup sequence control and the second and module 318 are both connected to the input end of the second or module 313. The output end of the second NOT module 316 and the output end of the second OR module 313 are both connected to the input end of the third AND module 319 , and the output end of the third AND module 319 is connected to the ReqA input end of the analog quantity hand operator unit 201 .

[0062] It should be noted that the 20th step of the BEST small steam turbine startup sequence is to put the No. 8 low-pressure heater into operation, the overflow valve into automatic operation, the back pressure controller and the final stage pressure ratio controller into operation, and the high back pressure limit value setting into operation. If the third and module 319 outputs a switch signal 1, it means that the current overflow valve is in the automatic operation state, the analog hand operator unit 201 switches to the automatic operation state, and outputs the received value of the X input terminal as the valve position instruction. In other words, if the BEST small steam turbine does not trip, and the bypass valve quick opening signal is not issued, and the BEST small steam turbine bypass is fully closed, and the No. 8 low-pressure heater is not cut off, and the 20th step of the BEST small steam turbine startup sequence is not triggered, and the bypass valve valve position control manual mode signal is not issued, the switch signal received by the ReqA input terminal of the analog hand operator unit 201 is 1, the analog hand operator module is in the automatic operation state, and the received value of the X input terminal is triggered.

[0063] In other embodiments of the present application, Figure 3 As shown, the automatic state identification unit 205 may also include a delay closing module 320. The switch signal input module 308 of the instruction of the 20th step of the BEST small steam turbine startup sequence control is connected to the input end of the delay closing module 320, and the output end of the delay closing module 320 and the output end of the second AND module 318 are both connected to the input end of the second OR module 313. In this way, the delay duration can be set by the delay closing module. When the switch signal input module 308 of the instruction of the 20th step of the BEST small steam turbine startup sequence control outputs a switch signal of 1, the output duration of the switch signal 1 can be extended, and the stability of the signal output can also be guaranteed, so as to avoid that when the BEST small steam turbine startup sequence control is completed, the signal received at the ReqA input end immediately becomes a switch signal 0, thereby improving the stability of the system control.

[0064] According to the overflow valve regulating control system of the BEST small steam turbine of the embodiment of the present application, the automatic state recognition unit, the tracking state recognition unit and the emergency state recognition unit are used to combine different working conditions to determine the control state of the overflow valve of the BEST small steam turbine, and the analog hand operator unit outputs the corresponding valve position instruction of the overflow valve of the BEST small steam turbine according to the control state of the overflow valve, so as to adjust the valve position of the bypass valve in real time. The system can be fully applicable to the equipment of the BEST small steam turbine with a small generator, and can not only automatically adjust the overflow valve according to different working conditions to avoid accidents and ensure the safe and stable operation of the BEST small steam turbine, but also achieve the goal of reducing staff and increasing efficiency.

[0065] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0066] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0067] In addition, each functional unit in each embodiment of the present application may be integrated into one processing module, or each unit may exist physically separately, or two or more units may be integrated into one module.

[0068] Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations on the present application. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A relief valve regulating control system applied to a BEST small steam turbine, characterized in that: The system comprises: The analog hand operator unit is used to output the valve position command of the BEST small steam turbine overflow valve according to the input data of each input terminal; An automatic command output unit, used for outputting a valve position command when the relief valve is in an automatic operation state according to a back pressure setting value and a final stage pressure ratio setting value of the BEST small steam turbine; the automatic command output unit is connected to the X input terminal of the analog quantity hand operator unit; An emergency state identification unit is used to output a signal indicating whether the BEST small steam turbine is in an emergency state according to the operating state of the BEST small steam turbine; the output end of the emergency state identification unit is connected to the ToM input end of the analog hand operator unit; A tracking state recognition unit, used for outputting a signal indicating whether the relief valve is in a tracking state according to an output signal of the emergency state recognition unit; an input end of the tracking state recognition unit is connected to an output end of the emergency state recognition unit, and an output end of the tracking state recognition unit is connected to a TS input end of the analog hand operator unit; An automatic state recognition unit, used for outputting a signal indicating whether the relief valve is in an automatic operation state according to the output signal of the emergency state recognition unit, the sequential control start-up progress of the BEST small steam turbine and the bypass valve state; the input end of the automatic state recognition unit is connected to the output end of the emergency state recognition unit, and the output end of the automatic state recognition unit is connected to the ReqA input end of the analog quantity hand operator unit; The analog signal output unit of the valve position instruction of the BEST small steam turbine overflow valve is connected to the signal output end of the analog hand operator unit.

2. The system according to claim 1, characterized in that The automatic command output unit includes an analog signal input module for the BEST small steam turbine back pressure setting value, an analog signal input module for the BEST small steam turbine final stage pressure ratio setting value, and a large value selection module; wherein: The analog signal input module of the BEST small steam turbine back pressure setting value and the analog signal input module of the BEST small steam turbine final stage pressure ratio setting value are both connected to the input end of the maximum value selection module, and the output end of the maximum value selection module is connected to the X input end of the analog quantity handheld operator unit.

3. The system according to claim 1, characterized in that The emergency state identification unit includes a switch signal input module for BEST small steam turbine tripping, a switch signal input module for bypass valve quick opening solenoid valve energized instruction, a first switch signal input module for BEST small steam turbine bypass valve full closing, a switch signal input module for No. 7 low-pressure heater removal, a switch signal input module for No. 8 low-pressure heater removal, a first or module, a first not module and a first and module; wherein: The first switch signal input module of the fully closed bypass valve of the BEST small steam turbine is connected to the input end of the first non-module; The switch quantity signal input module for the removal of the No. 7 low-pressure heater and the switch quantity signal input module for the removal of the No. 8 low-pressure heater are both connected to the input end of the first module; The switch signal input module for the BEST small steam turbine tripping, the switch signal input module for the bypass valve quick opening solenoid valve energized instruction, the output end of the first non-module, the output end of the first and module, and the switch signal input module for the No. 8 low-pressure heater cutoff are all connected to the input end of the first or module.

4. The system according to claim 1, characterized in that The tracking state identification unit comprises a pulse module, the input end of the pulse module is connected to the output end of the emergency state identification unit, and the output end of the pulse module is connected to the TS input end of the analog hand operator unit.

5. The system according to claim 1, characterized in that The automatic state recognition unit includes a switch signal input module for the instruction of the 20th step of the BEST small steam turbine startup sequence control, a second switch signal input module for the BEST small steam turbine bypass valve to be fully closed, a switch signal input module for the bypass valve position control manual mode, a second NOT module, a second AND module, a second OR module and a third AND module; wherein: The input end of the second non-module is connected to the output end of the emergency state identification unit; The second switch signal input module of the bypass valve of the BEST small steam turbine fully closed and the switch signal input module of the bypass valve position control manual mode are both connected to the input end of the second AND module; the switch signal input module of the instruction of the 20th step of the BEST small steam turbine startup sequence control and the output end of the second AND module are both connected to the input end of the second OR module; The output end of the second NOT module and the output end of the second OR module are both connected to the input end of the third AND module, and the output end of the third AND module is connected to the ReqA input end of the analog quantity hand operator unit.

6. The system according to claim 5, characterized in that The automatic state recognition unit also includes a time-delay closing module; wherein: The switch signal input module of the instruction of the twentieth step of the BEST small steam turbine startup sequence control is connected to the input end of the delayed closing module, and the output end of the delayed closing module and the output end of the second and module are both connected to the input end of the second or module.

7. The system according to claim 1, characterized in that Also includes: A first constant unit connected to the TR input terminal of the analog hand operator unit, wherein the preset value in the first constant unit is 0.

8. The system according to any one of claims 1 to 7, characterized in that: Also includes: A second constant unit is used to set a high limit value of the output of the analog hand operator unit; the second constant unit is connected to the MaxOut input terminal of the analog hand operator unit; The third constant unit is used to set the lower limit value of the output of the analog hand operator unit; the third constant unit is connected to the MinOut input terminal of the analog hand operator unit.

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