CN115387863A - BEST small steam turbine steam admission governing valve control system based on automatic undisturbed switching of multiplex condition - Google Patents

Abstract

This application is about a BEST small steam turbine inlet steam control system based on automatic non-disturbance switching of multiple working conditions. The specific plan is: the digital signal input module through the fault of the converter, the digital signal input module of the emergency stop of the converter, the digital signal input module of the main control state of the converter, and the simulation of the BEST small steam turbine speed setting value Quantity signal input module, analog signal input module of BEST small steam turbine actual speed value, analog signal input module of BEST small steam turbine actual load, converter failure or emergency stop condition inlet steam control unit and BEST small steam turbine rejection The steam inlet control unit under load conditions adjusts the opening of the inlet steam valve of the BEST small steam turbine according to different working conditions. The application can adapt the converter in the failure or emergency stop condition and the BEST small steam turbine in the load shedding condition, and improves the flexibility and accuracy of controlling the opening of the BEST small steam turbine's inlet steam valve.

Description

BEST Small Steam Turbine Intake Steam Control System Based on Multi-working Condition Automatic Undisturbed Switching

technical field

The present application relates to the technical field of control of ultra-supercritical double-reheat coal-fired units, and in particular to a BEST small steam turbine inlet steam control system based on automatic non-disturbance switching of multiple working conditions.

Background technique

In the related technology, the ultra-supercritical double reheat coal-fired unit BEST small steam turbine with a small generator has its own unique structural properties and various operation and start-up methods, so a large number of tests need to be carried out during commissioning and research. The operating parameters and operating states reflected by the BEST small steam turbine under various working conditions are summarized, and combined with the control strategy formulated by the original manufacturer, it is improved and optimized. When the converter is in fault or emergency stop condition and the BEST small steam turbine is in the load rejection condition, the original control strategy of the BEST small steam turbine inlet steam valve cannot fully apply to these two conditions, resulting in The problem of inaccurate control operation target and inaccurate control operation parameters.

Contents of the invention

For this reason, this application provides a BEST small steam turbine inlet steam valve control system based on automatic non-disturbance switching of multiple working conditions. The technical scheme of the application is as follows:

According to the first aspect of the embodiment of the present application, there is provided a BEST small steam turbine intake steam control system based on multi-working condition automatic non-disturbance switching, the system includes a converter fault switch signal input module, a converter emergency Switch signal input module for stop, switch signal input module for main control state of converter, analog signal input module for BEST small steam turbine speed setting value, analog signal input module for BEST small steam turbine actual speed value, BEST small steam turbine The analog signal input module of the actual load of the steam turbine, the steam inlet control unit of the converter failure or emergency stop condition, the BEST small steam turbine load rejection condition intake steam control unit, the converter failure or emergency stop condition The steam intake control unit includes a converter failure or emergency stop condition determination subunit, a first subtraction subunit, and a first control subunit, and the BEST small steam turbine load rejection control unit includes a BEST small steam turbine The load shedding condition determination subunit, the second subtraction subunit and the second gate control subunit, wherein,

The switch signal input module for the converter fault, the switch signal input module for the emergency stop of the converter, and the switch signal input module for the main control state of the converter are respectively connected with the converter fault or emergency stop working condition Determine the subunit connection, the analog signal input module of the actual speed value of the BEST small steam turbine is connected to the first subtraction subunit, the converter failure or emergency stop working condition determination subunit, the BEST small steam turbine speed setting The value analog signal input module and the first subtraction subunit are respectively connected with the first gate control subunit;

The analog signal input module of the actual load of the BEST small steam turbine, the analog signal input module of the actual speed value of the BEST small steam turbine, the switch signal input module of the converter fault, and the switch signal input module of the emergency stop of the converter The switching signal input module of the main control state of the converter is respectively connected with the BEST small steam turbine load shedding working condition determination subunit, the analog signal input module of the BEST small steam turbine speed setting value, and the BEST small steam turbine actual speed value. The analog signal input module is respectively connected to the second subtraction subunit, and the BEST small steam turbine load rejection subunit and the second subtraction subunit are respectively connected to the second gate control subunit.

According to an embodiment of the present application, the converter fault or emergency stop working condition determining subunit includes a first OR module, a first non-module and a first AND module, wherein,

The switching signal input module for the converter failure and the switching signal input module for the emergency stop of the converter are respectively connected to the input terminals of the first or module;

The switching signal input module of the main control state of the converter is connected to the input terminal of the first non-module;

The output end of the first or module and the output end of the first non-module are respectively connected to the input end of the first and module;

The output end of the first AND module is connected to the first door adjustment subunit.

According to an embodiment of the present application, the first subtraction subunit includes a first subtraction module, wherein,

The analog signal input module of the actual speed value of the BEST small steam turbine is connected to the input end of the first subtraction module, and the output end of the first subtraction module is connected to the first gate control subunit;

The analog signal input module of the actual rotational speed value of the BEST small steam turbine is connected with the first throttle control subunit.

According to an embodiment of the present application, the first gate control subunit includes an alternative switching module, a second subtraction module, a first PID module, a first function f(x) converter module, and the first BEST small steam turbine The analog signal output module of the opening degree of the steam inlet valve, wherein,

The output terminal of the first AND module is connected to the EN terminal of the one-of-two switching module, and the analog signal input module of the BEST small steam turbine speed setting value is connected to the N-terminal of the one-two switching module, The output terminals of the first subtraction module are respectively connected to the Y terminals of the one-of-two switching module;

The output end of the two-choice switching module is connected to the first input end of the second subtraction module, and the analog signal input module of the actual speed value of the BEST small steam turbine is connected to the second input end of the second subtraction module. connect;

The output end of the second subtraction module is sequentially connected to the first PID module, the first function f(x) converter module and the analog signal output module of the inlet steam valve opening of the first BEST small steam turbine.

According to an embodiment of the present application, the BEST small steam turbine load rejection subunit includes a second OR module, a second non-module, a second AND module, a pulse module, a hysteresis module and a comparison module, and a third AND module ,in,

The switching signal input module for the converter failure and the switching signal input module for the emergency stop of the converter are respectively connected to the input end of the second or module;

The switching signal input module of the main control state of the converter is connected to the input terminal of the second non-module;

The output end of the second or module and the output end of the second non-module are respectively connected to the input end of the first AND module, and the output end of the first AND module is connected to the input end of the pulse module ;

The analog signal input module of the actual load of the BEST small steam turbine is connected to the lagging module in turn, and the input terminal of the comparison module is greater than; wherein, the comparison ratio module is used to determine the load value output by the lagging module and the first preset value. The comparison result obtained by comparing the load value;

The output end of the pulse module and the output end of the comparative treatment module are respectively connected to the input end of the third AND module;

The output end of the third AND module is connected to the second gate control subunit.

According to an embodiment of the present application, the first preset load value is 5MW.

According to an embodiment of the present application, the second subtraction subunit includes a third subtraction module, wherein,

The analog signal input module of the BEST small steam turbine actual speed value and the analog signal input module of the BEST small steam turbine speed set value are respectively connected to the input end of the third subtraction module;

The output end of the third subtraction module is connected to the second gate control subunit.

According to an embodiment of the present application, the second door adjustment control subunit includes a switch output module with the quick-closing solenoid valve charged and the steam inlet air door instruction cleared, a second PID module, and a second function f(x) converter module and the analog signal output module of the inlet steam valve opening of the second BEST small steam turbine, wherein,

The output end of the third AND module is connected to the switch output module that is charged with the quick-closing solenoid valve and cleared the instruction of the steam inlet adjustment door;

The output end of the third AND module and the output end of the third subtraction module are respectively connected to the input end of the second PID module;

The output end of the second PID module is sequentially connected to the second function f(x) converter module and the analog signal output module of the inlet steam valve opening of the second BEST small steam turbine.

The technical solutions provided by the embodiments of the present application bring at least the following beneficial effects:

The opening of the inlet steam valve of the BEST small steam turbine is controlled by the control unit of the inlet steam valve under the converter failure or emergency stop condition and the inlet steam valve control unit of the BEST small steam turbine load rejection condition according to different working conditions. Therefore, the system can adapt the converter in the fault or emergency stop condition and the BEST small steam turbine in the load rejection condition, and improves the flexibility and accuracy of the control of the opening of the BEST small steam turbine's inlet steam valve.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Description of drawings

The accompanying drawings here are incorporated into the specification and constitute a part of the specification, show the embodiment consistent with the application, and are used together with the specification to explain the principle of the application, and do not constitute an improper limitation of the application.

Fig. 1 is a structural block diagram of a BEST small steam turbine inlet steam control system based on multi-working condition automatic non-disturbance switching in the embodiment of the present application;

Figure 2 is a schematic diagram of the control flow of the BEST small steam turbine inlet steam valve when the converter is in fault or emergency stop condition;

Fig. 3 is a schematic diagram of the control flow of the BEST small steam turbine inlet steam valve when the BEST small steam turbine is in the load shedding condition.

Detailed ways

In order to enable ordinary persons in the art to better understand the technical solutions of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings.

It should be noted that the terms "first" and "second" in the description and claims of the present application and the above drawings are used to distinguish similar objects, but not necessarily used to describe a specific sequence or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances such that the embodiments of the application described herein can be practiced in sequences other than those illustrated or described herein. The implementations described in the following exemplary embodiments do not represent all implementations consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with aspects of the present application as recited in the appended claims.

It should be noted that, in related technologies, the ultra-supercritical double reheat coal-fired unit BEST small steam turbine with a small generator has its own unique structural properties and various operation and start-up methods, so it needs to be carried out during commissioning and research. Through a large number of tests, the operating parameters and operating states reflected in various working conditions of the BEST small steam turbine are summarized, and combined with the control strategy formulated by the original manufacturer, it is improved and optimized. When the converter is in fault or emergency stop condition and the BEST small steam turbine is in the load rejection condition, the original control strategy of the BEST small steam turbine inlet steam valve cannot fully apply to these two conditions, resulting in The problem of inaccurate control operation target and inaccurate control operation parameters.

Based on the above problems, this application proposes a BEST small steam turbine inlet steam control system based on multi-working condition automatic non-disturbance switching, which can shed load through the converter failure or emergency stop condition inlet steam control unit and BEST small steam turbine The operating condition steam inlet control unit adjusts the opening of the BEST small steam turbine inlet steam valve according to different working conditions. Therefore, the system can adapt the converter in the fault or emergency stop condition and the BEST small steam turbine in the load rejection condition, and improves the flexibility and accuracy of the control of the opening of the BEST small steam turbine's inlet steam valve.

Fig. 1 is a structural block diagram of a BEST small steam turbine intake steam valve control system based on automatic non-disturbance switching of multiple working conditions in the embodiment of the present application.

As shown in Fig. 1, the BEST small steam turbine inlet steam control system based on multi-working condition automatic non-disturbance switching includes: a switch signal input module 102 for converter failure, and a switch signal input module 103 for converter emergency stop , the switching signal input module 104 of the main control state of the converter, the analog signal input module 105 of the BEST small steam turbine speed setting value, the analog signal input module 106 of the actual speed value of the BEST small steam turbine, the actual load of the BEST small steam turbine The analog signal input module 101, the steam inlet control unit 107 of the converter fault or emergency stop condition, the steam intake control unit 108 of the BEST small steam turbine load rejection condition, and the steam intake control unit of the converter failure or emergency stop condition The control unit 107 includes a converter failure or emergency stop working condition determination subunit 1071, a first subtraction subunit 1072, and a first adjustment door control subunit 1073, and the BEST small steam turbine load rejection condition inlet steam adjustment control unit 108 includes The load rejection condition determination subunit 1081 , the second subtraction subunit 1082 and the second gate control subunit 1083 .

Among them, the switching signal input module 102 for converter failure, the switching signal input module 103 for emergency stop of the converter, and the switching signal input module 104 for the main control state of the converter are respectively connected with the converter fault or emergency shutdown. The condition determination subunit 1071 is connected, the analog signal input module 106 of the actual speed value of the BEST small steam turbine is connected with the first subtraction subunit 1072, and the subunit 1071 for determining the converter fault or emergency stop working condition and the set value of the BEST small steam turbine speed The analog signal input module 105 and the first subtraction subunit 1072 are connected to the first gate control subunit 1073 respectively.

In some embodiments of the present application, as shown in FIG. 2 , the converter fault or emergency stop working condition determination subunit includes a first OR module 207, a first non-module 208, and a first AND module 209, wherein the converter The fault switch signal input module 201 and the converter emergency stop switch signal input module 202 are respectively connected to the input terminals of the first or module 207; the switch signal input module of the converter main control state is connected to the first non-module The input end of 208 is connected; the output end of the first or module 207, the output end of the first non-module 208 are respectively connected with the input end of the first and module 209; the output end of the first and module 209 is connected with the first gate control subunit connect.

As a possible example, when the converter is not faulty, the output signal of the converter fault digital signal input module 201 is 1; when the converter does not have an emergency stop condition, the converter emergency stop The output signal of the switch value signal input module 202 is 1. If the binary signal input module 201 for converter failure and the binary signal input module 202 for emergency stop of the converter both output binary signals of 1, then the output signal of the first OR module 207 is 1. When the converter is in the master control state, the output signal of the switch signal input module in the master control state of the converter is 1, and the output signal of the first non-module 208 is 0. When the switching value signals output by the first OR module 207 and the first non-module 208 are both 1, the output signal of the first OR module 209 is 1, indicating that the current working condition is a normal working condition, and the two-choice switching module 211 outputs The terminal is the “N” terminal of the one-of-two switching module 211 .

As another possible example, when a converter fails, the output signal of the converter fault digital signal input module 201 is 0; The output signal of the switching value signal input module 202 is 0. If any one of the switch signal input module 201 for converter failure and the switch signal input module 202 for emergency stop outputs a switch signal of 0, the output signal of the first OR module 207 is 0. When the converter is not in the master control state, the output signal of the switch signal input module in the master control state of the converter is 0, and the output signal of the first non-module 208 is 1. When the switch signal output by any one of the first OR module 207 and the first non-module 208 is 0, the output signal of the first AND module 209 is 0, indicating that the current working condition is a converter failure or emergency stop condition , the output terminal of the one-two switching module 211 is the “Y” terminal of the one-two switching module 211 .

In some embodiments of the present application, as shown in FIG. 2 , the first subtraction subunit includes a first subtraction module 210, wherein the analog signal input module 205 of the actual speed value of the BEST small steam turbine is connected to the input terminal of the first subtraction module 210 connection, the output terminal of the first subtraction module 210 is connected with the first gate control subunit; the analog signal input module 205 of the actual speed value of the BEST small steam turbine is connected with the first gate control subunit.

In some embodiments of the present application, the first gate control subunit includes an alternative switching module 211, a second subtraction module 212, a first PID module 213, a first function f(x) converter module 214 and a first BEST small The analog signal output module 206 of the opening of the inlet steam valve of the steam turbine, wherein the output terminal of the first and module 209 is connected to the EN terminal of the two-choice switching module 211, and the analog signal input module of the BEST small steam turbine speed setting value 204 is connected with the N end of the one-two switching module 211, and the output end of the first subtraction module 210 is connected with the Y end of the one-two switching module 211 respectively; The first input terminal is connected, and the analog signal input module 205 of the BEST small steam turbine actual speed value is connected with the second input terminal of the second subtraction module 212; the output terminal of the second subtraction module 212 is connected successively with the first PID module 213, the first The function f(x) converter module 214 and the analog signal output module 206 of the opening degree of the inlet steam valve of the first BEST small steam turbine.

It should be noted that the function of the two-to-one switching module 211 is that when the "EN" terminal receives the switching signal "0" output by the first AND module 209, its output terminal is the "N" terminal of the two-to-one switching module 211 , when the EN terminal receives the switching signal “1” output by the first AND module 209 , its output terminal is the Y terminal of the two-to-one switching module 211 .

In normal operating conditions, the switch signal output by the first and module 209 is "0", the EN terminal of the two-to-one switch module 211 cannot be triggered, and the switch signal will be kept at "0", and the two-to-one switch module 211 Using the N terminal as the input end, the output result is the BEST small steam turbine speed set value input by the analog signal input module 204 of the BEST small steam turbine speed set value; the second subtraction module 212 receives the above-mentioned BEST small steam turbine speed set value and After the analog signal input module 205 of the actual speed value of the BEST small steam turbine has input the actual speed value of the BEST small steam turbine, the set value of the speed of the BEST small steam turbine is subtracted from the actual speed value of the BEST small steam turbine to obtain a deviation value and output it to the first PID Module 213. The first PID module 213 performs PID adjustment on the deviation value, calculates the inlet steam valve opening value of the BEST small steam turbine through the first function f(x) converter module 214, and inputs the inlet steam valve opening value of the BEST small steam turbine into An analog signal output module 206 of the opening degree of the inlet steam valve of the first BEST small steam turbine.

As a possible example, the function of the first PID module 213 is that when there is a deviation in the process itself, the output of the first PID module 213 will constantly change, and the output will make the deviation change to a decreasing direction; the first function f(x) The function of the converter module 214 is that F(x) is a function set including twelve segments of broken lines, and the first function f(x) converter module 214 uses the function set to perform interpolation operations according to the range of the input end to obtain an output value .

When the converter is faulty or in an emergency stop condition, the switching signal output by the first and module 209 is "1", and the EN terminal of the switching module 211 will trigger to keep the switching signal at "1". Select one switching module 211 to use the "Y" terminal as the input terminal, and the output result is the analog signal signal input module 205 output of the BEST small steam turbine actual speed value and the preset value X in the first subtraction module 210. The first difference obtained after the subtraction calculation; the above-mentioned first difference and the actual speed value of the BEST small steam turbine are input into the second subtraction module 212, and the second subtraction module 212 compares the first difference with the actual speed value of the BEST small steam turbine Subtract, obtain and output its deviation value, use the first PID module 213 to carry out PID adjustment to the deviation value, calculate the intake steam valve opening value of the BEST small steam turbine through the first function f(x) converter module 214, and the BEST small steam turbine The inlet steam valve opening value of the steam turbine is input to the analog signal output module 206 of the inlet steam valve opening of the first BEST small steam turbine.

It is understandable that when the converter fails, the speed of the BEST small steam turbine will drop rapidly, and the opening of the BEST small steam turbine's inlet steam valve will also decrease accordingly. After subtracting the above preset value X from the actual speed value of the BEST small steam turbine, the resulting value must be smaller than the actual speed value of the BEST small steam turbine. The opening of the inlet steam valve of the BEST small steam turbine can be adjusted through this result value, which can advance Control the rotational speed within a reasonable range to prevent the opening of the inlet steam valve of the BEST small steam turbine from dropping too fast.

As shown in Figure 1, the analog signal input module 101 of the actual load of the BEST small steam turbine, the analog signal input module 106 of the actual speed value of the BEST small steam turbine, the switch signal input module 102 of the converter failure, the converter emergency The switching signal input module 103 for stopping and the switching signal input module 104 for the main control state of the converter are respectively connected to the subunit 1081 for determining the load shedding condition of the BEST small steam turbine, and the analog signal input module for the speed setting value of the BEST small steam turbine 105. The analog signal input module 106 of the actual speed value of the BEST small steam turbine is respectively connected to the second subtraction subunit 1082, and the BEST small steam turbine load shedding working condition determination subunit 1081 and the second subtraction subunit 1082 are respectively connected to the second adjustment gate control subunit. Unit 1083 is connected.

It should be noted that load shedding means that due to the reduction of end-user electricity load (such as large-scale electrical equipment failure or large-area area line failure), the power generation of the turbine generator in the power plant exceeds the amount delivered to the user. At this time, the power plant is required to reduce the power generation to a value suitable for the actual load. Or due to internal reasons in the power plant, the circuit breaker at the outlet of the power supply network suddenly trips, and the load of the turbogenerator suddenly drops to almost zero. These actions of the power plant are called load shedding.

In some embodiments of the present application, as shown in FIG. 3 , the BEST small steam turbine load rejection determination subunit includes a second OR module 309, a second non-module 310, a second AND module 311, a pulse module 318, and a hysteresis module 313 The sum is larger than the module 314 and the third AND module 312, wherein the switching signal input module 302 of the converter failure and the switching signal input module 303 of the emergency stop of the converter are respectively connected to the input terminals of the second OR module 309; The switch signal input module 304 of the main control state of the converter is connected to the input end of the second non-module 310; the output end of the second or module 309 and the output end of the second non-module 310 are respectively connected to the input ends of the first and module Connection, the output end of the first module is connected with the input end of the pulse module 318; the analog signal input module 306 of the actual load of the BEST small steam turbine is connected to the lagging module 313 in turn, and the input end of the relatively greater module 314; wherein, the greater than the module 314 is used to determine the comparison result obtained by comparing the load value output by the hysteresis module 313 with the first preset load value; the output terminal of the pulse module 318 and the output terminal of the comparison module 314 are respectively connected to the input terminal of the third AND module 312 ; The output terminal of the third AND module 312 is connected with the second gate control subunit.

As a possible example, when the converter is not faulty, the output signal of the converter fault digital signal input module 302 is 1; when the converter does not have an emergency stop condition, the converter emergency stop The output signal of the switching value signal input module 303 is 1. If the binary signal input module 302 for converter failure and the binary signal input module 303 for emergency stop of the converter both output binary signals of 1, then the output signal of the second OR module 309 is 1. When the converter is in the main control state, the output signal of the switch signal input module 304 in the main control state of the converter is 1, and the output signal of the second non-module 310 is 0. When the switching value signals output by the second OR module 309 and the second NOT module 310 are both 1, the output signal of the second AND module 311 is 1.

As another possible example, when a converter fails, the output signal of the converter fault digital signal input module 302 is 0; The output signal of the switching value signal input module 303 is 0. If any one of the switch signal input module 302 for converter failure and the switch signal input module 303 for emergency stop outputs a switch signal of 0, the output signal of the second OR module 309 is 0. When the converter is not in the main control state, the output signal of the switch signal input module 304 in the main control state of the converter is 0, and the output signal of the second non-module 310 is 1. When the switch signal output by any one of the second OR module 309 and the second non-module 310 is 0, the output signal of the second AND module 311 is 0.

It should be noted that the output signals of the switching signal input module 302 for converter failure, the switching signal input module 303 for emergency stop of the converter, and the switching signal input module 304 for the main control state of the converter all have delays. , so it is necessary to lag the output signal of the analog signal input module 306 of the actual load of the BEST small steam turbine through the hysteresis module 313, so as to ensure the consistency of the above-mentioned multiple modules.

In some embodiments of the present application, the first preset load value is 5MW.

In some embodiments of the present application, as shown in FIG. 3 , the second subtraction subunit includes a third subtraction module 315, wherein, the analog signal input module of the actual speed value of the BEST small steam turbine, the simulation of the speed set value of the BEST small steam turbine The quantity signal input module 305 is respectively connected to the input end of the third subtraction module 315; the output end of the third subtraction module 315 is connected to the second gate control subunit.

In some embodiments of the present application, the second door adjustment control subunit includes a switching value output module 307 with the quick-closing solenoid valve charged and the steam inlet air door instruction cleared, a second PID module 316, and a second function f(x) converter module 317 and the analog signal output module 308 of the inlet steam valve opening of the second BEST small steam turbine, wherein, the output terminal of the third AND module 312 is charged with the fast closing solenoid valve and the switching value output module 307 of which the steam inlet valve command is cleared Connect; the output end of the third AND module 312 and the output end of the third subtraction module 315 are respectively connected with the input end of the second PID module 316; the output end of the second PID module 316 is connected with the second function f(x) converter in turn Module 317 and the analog quantity signal output module 308 of the opening degree of the inlet steam valve of the second BEST small steam turbine.

During the normal working condition of the BEST small steam turbine before load shedding and after the BEST small steam turbine load shedding, the analog signal input module 306 of the BEST small steam turbine actual speed value output by the BEST small steam turbine actual speed value and the BEST small steam turbine speed set value The BEST small steam turbine speed setting value output by the analog signal input module 305 is subtracted by the third subtraction module 315 to obtain a deviation value, and the third subtraction module 315 outputs the deviation value to the second PID module 316, and the second PID module 316 compares the deviation value Perform PID adjustment, calculate the inlet steam valve opening value of the BEST small steam turbine through the second function f(x) converter module 317, and input the inlet steam valve opening value of the BEST small steam turbine to the inlet steam valve of the second BEST small steam turbine An analog signal output module 308 for adjusting the door opening.

When the current working condition is the BEST small steam turbine load shedding condition, first the analog signal input module 306 of the actual load of the BEST small steam turbine outputs the actual load value of the BEST small steam turbine to the first comparison module 314 through the first hysteresis module 313 , when the actual load value of the BEST small steam turbine is greater than the preset load value, it means that the BEST small steam turbine has the conditions for load shedding operation at this time. At this time, the load shedding operation is triggered, thereby triggering the switching signal input module 302 of the converter failure or the switching signal input module 303 of the emergency stop of the converter, and the switching signal input module 304 of the main control state of the converter sends a switch Quantity signal is 0. The third AND module 312 outputs the switching signal 1 to the switching output module 307 where the quick-closing solenoid valve is charged and the steam inlet adjustment command is cleared, thereby triggering the switching output module 307 where the quick-closing solenoid valve is charged and the steam inlet adjustment command is cleared. Control the quick-closing solenoid valve to perform 1s quick-closing and control the command of steam inlet adjustment to clear. The third AND module 312 outputs the switching signal 1 to the second PID module 316, thereby triggering the tracking switch TS of the second PID module 316, making the tracking value TR be "0", and the adjustment door performs a fast closing action of 1s; when the BEST small steam turbine After the inlet steam valve closes quickly for 1 second, the second PID module 316 will continue to perform PID adjustment on the deviation value, and the second function f(x) converter module 317 will calculate the inlet steam valve opening value of the BEST small steam turbine. The opening value of the inlet steam regulating valve of the BEST small steam turbine is input to the analog signal output module 308 of the inlet steam regulating valve opening of the second BEST small steam turbine.

It should be noted that the function of the second PID module 316 is that when there is a deviation in the process itself, the output of the second PID module 316 will continue to change, and the output will make the deviation change in the direction of decreasing. When the tracking switch Ts is triggered, it will output itself The internally set tracking value Tr continues to be adjusted by the second PID module 316 to the deviation value; the function of the second function f(x) converter module 317 is, F(x) is a function set comprising twelve segments, The second function f(x) converter module 317 uses the function set to perform interpolation calculation according to the range of the input end, and obtains the output value of the inlet steam valve opening of the BEST small steam turbine.

According to the BEST small steam turbine inlet steam control system based on multi-working condition automatic non-disturbance switching according to the embodiment of the application, the steam inlet control unit under the converter failure or emergency stop condition and the BEST small steam turbine load rejection condition inlet steam control unit The control unit adjusts the opening of the inlet steam door of the BEST small steam turbine according to different working conditions. Therefore, the system can adapt the converter in the fault or emergency stop condition and the BEST small steam turbine in the load rejection condition, and improves the flexibility and accuracy of the control of the opening of the BEST small steam turbine's inlet steam valve.

In describing the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " Back", "Left", "Right", "Vertical", "Horizontal", "Top", "Bottom", "Inner", "Outer", "Clockwise", "Counterclockwise", "Axial", The orientation or positional relationship indicated by "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying the referred device or element Must be in a particular orientation, be constructed in a particular orientation, and operate in a particular orientation, and therefore should not be construed as limiting the invention.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

In the present invention, unless otherwise clearly specified and limited, terms such as "installation", "connection", "connection" and "fixation" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection , or integrated; can be mechanically connected, can also be electrically connected or can communicate with each other; can be directly connected, can also be indirectly connected through an intermediary, can be the internal communication of two components or the interaction relationship between two components, unless expressly defined otherwise. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention according to specific situations.

In the present invention, unless otherwise clearly specified and limited, the first feature may be in direct contact with the first feature or the first and second feature may be in direct contact with the second feature through an intermediary. touch. Moreover, "above", "above" and "above" the first feature on the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. "Below", "beneath" and "beneath" the first feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is less horizontally than the second feature.

As used herein, the terms "one embodiment," "some embodiments," "example," "specific examples," or "some examples" mean specific features, structures, materials, or features described in connection with the embodiment or example. A feature is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention, those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (8)

1. A BEST small steam turbine admission governing valve control system based on multi-operating mode automatic undisturbed switching is characterized by comprising a switching value signal input module of converter faults, a switching value signal input module of converter sudden stop, a switching value signal input module of a converter master control state, an analog quantity signal input module of a BEST small steam turbine rotating speed set value, an analog quantity signal input module of a BEST small steam turbine actual rotating speed value, an analog quantity signal input module of actual loads of a BEST small steam turbine, a converter fault or sudden stop operating mode admission governing valve control unit and a BEST small steam turbine load shedding operating mode admission governing valve control unit, wherein the converter fault or sudden stop operating mode admission governing valve control unit comprises a converter fault or sudden stop determining stator unit, a first subtraction subunit and a first governing valve control subunit, the BEST small steam turbine load shedding operating mode admission governing valve control unit comprises a BEST small steam turbine load shedding operating mode determining stator unit, a second subtraction subunit and a second governing valve control subunit, wherein the converter fault or sudden stop operating mode admission control subunit is controlled by the first subtraction sub-unit,

the converter fault switching value signal input module, the converter sudden stop switching value signal input module and the converter master control state switching value signal input module are respectively connected with the converter fault or sudden stop working condition determining subunit, the BEST small turbine actual rotating speed value analog quantity signal input module is connected with the first subtraction subunit, and the converter fault or sudden stop working condition determining subunit, the BEST small turbine rotating speed set value analog quantity signal input module and the first subtraction subunit are respectively connected with the first gate control subunit;

the analog quantity signal input module of the actual load of the BEST small turbine, the analog quantity signal input module of the actual rotating speed value of the BEST small turbine, the switching quantity signal input module of the fault of the converter, the switching quantity signal input module of the sudden stop of the converter and the switching quantity signal input module of the main control state of the converter are respectively connected with the load shedding working condition determining subunit of the BEST small turbine, the analog quantity signal input module of the rotating speed set value of the BEST small turbine and the analog quantity signal input module of the actual rotating speed value of the BEST small turbine are respectively connected with the second subtracting subunit, and the load shedding working condition determining subunit of the BEST small turbine and the second subtracting subunit are respectively connected with the second throttle control subunit.

2. The system of claim 1, wherein the converter fault or scram condition determination subunit comprises a first OR module, a first NOT module, and a first AND module, wherein,

the converter fault switching value signal input module and the converter emergency stop switching value signal input module are respectively connected with the input end of the first OR module;

the switching value signal input module in the master control state of the converter is connected with the input end of the first non-module;

the output end of the first OR module and the output end of the first NOT module are respectively connected with the input end of the first AND module;

and the output end of the first AND module is connected with the first gate adjusting control subunit.

3. The system of claim 2, wherein the first subtraction sub-unit comprises a first subtraction module, wherein,

an analog quantity signal input module of the actual rotating speed value of the BEST small turbine is connected with the input end of the first subtraction module, and the output end of the first subtraction module is connected with the first gate regulating control subunit;

and the analog quantity signal input module of the actual rotating speed value of the BEST small turbine is connected with the first gate control subunit.

4. The system of claim 3, wherein the first throttle control subunit includes an alternative switching module, a second subtraction module, a first PID module, a first function f (x) converter module, and an analog signal output module of the inlet throttle opening of the first BEST small turbine, wherein,

the output end of the first and module is connected with the EN end of the alternative switching module, the analog quantity signal input module of the rotation speed set value of the BEST small steam turbine is connected with the N end of the alternative switching module, and the output end of the first subtraction module is respectively connected with the Y end of the alternative switching module;

the output end of the alternative switching module is connected with the first input end of the second subtraction module, and the analog quantity signal input module of the actual rotating speed value of the BEST small steam turbine is connected with the second input end of the second subtraction module;

the output end of the second subtraction module is sequentially connected with the first PID module, the first function f (x) converter module and the analog quantity signal output module of the opening degree of the steam inlet regulating valve of the first BEST small steam turbine.

5. The system of claim 1, wherein the BEST small turbine load shedding condition determining subunit comprises a second OR module, a second NOT module, a second AND module, a pulse module, a lag module, and a compare greater module, a third AND module, wherein,

the switching value signal input module of the converter fault and the switching value signal input module of the converter sudden stop are respectively connected with the input end of the second OR module;

the switching value signal input module in the master control state of the converter is connected with the input end of the second non-module;

the output end of the second OR module and the output end of the second NOT module are respectively connected with the input end of the first AND module, and the output end of the first AND module is connected with the input end of the pulse module;

the analog quantity signal input module of the actual load of the BEST small turbine is sequentially connected with the hysteresis module and the input end of the comparison larger module; the comparison greater module is used for determining a comparison result obtained by comparing the load value output by the hysteresis module with a first preset load value;

the output end of the pulse module and the output end of the comparison treatment module are respectively connected with the input end of the third and module;

and the output end of the third AND module is connected with the second gate adjusting control subunit.

6. The system according to claim 5, characterized in that said first preset load value is 5MW.

7. The system of claim 5, wherein the second subtraction sub-unit comprises a third subtraction module, wherein,

the analog quantity signal input module of the actual rotating speed value of the BEST small turbine and the analog quantity signal input module of the rotating speed set value of the BEST small turbine are respectively connected with the input end of the third subtraction module;

and the output end of the third subtraction module is connected with the second gate adjusting control subunit.

8. The system according to claim 7, wherein the second throttle control subunit includes a switching value output module in which the fast-closing solenoid valve is charged and the steam intake throttle command is cleared, a second PID module, a second function f (x) converter module, and an analog quantity signal output module of the steam intake throttle opening of the second BEST small steam turbine, wherein,

the output end of the third AND module is connected with a switching value output module which is electrified and the steam inlet governing valve is cleared;

the output end of the third sum module and the output end of the third subtraction module are respectively connected with the input end of the second PID module;

and the output end of the second PID module is sequentially connected with the second function f (x) converter module and an analog quantity signal output module of the opening degree of a steam inlet regulating valve of the second BEST small steam turbine.

Images