Multi-signal switching speed limit control system

Abstract

The invention relates to a multi-signal switching speed-limiting control system, which comprises an input signal switching module, a switching process rate-increasing selection module, a switching process rate-decreasing selection module, a rate limiting enabling module, an output signal rate setting and speed-limiting module and an output signal receiving module, in a control system which does not have a speed limiting function for a multi-signal switching process, setting of different change rates in the switching process of different signal sources can be realized, control requirements are met, speed limiting is performed on the signal switching process with multiple signal sources, functional defects in the control system are made up, and the method is an important functional design in control strategy establishment; the switching process rates under multiple channels are independently set, so that the flexibility of switching process rate control is improved; the method is built based on basic modules in various types of control systems, the engineering applicability is good, and high operability and popularization value are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of signal switching in a control system, and in particular to a multi-signal switching speed limiting control method. Background Art

[0002] In the signal transmission system of the control system, the signal switching module is used to collect multi-channel signals from multiple signal sources, configure transmission links for the collected signals, and transmit them to the next-level module for display or control. Among them, the signal source channel selection signal and each signal source are respectively connected to an input port of the signal switching module, and the next-level module for display or control is connected to the output port of the signal switching module. In actual applications, users can switch the transmission signal received by the display or control module according to their needs. In order to ensure the smoothness of the switching process and eliminate signal jitter during the switching process, it is also necessary to set different change rates for the switching process of different signal sources.

[0003] However, many types of control systems currently do not have the function of limiting the speed of the multi-signal switching process, which results in significant jumps in important signals that need to be switched, increased system interference, and severe disturbances in the control quantity, which seriously damage the life of the controlled equipment and even affect the smooth operation of the system, bringing safety hazards. Therefore, improvement and innovation are imperative. Summary of the invention

[0004] In view of the above situation, in order to overcome the shortcomings of the prior art, the purpose of the present invention is to provide a multi-signal switching speed limit control system, which can realize the setting of different change rates during the switching process of different signal sources in a control system that does not have the speed limit function of the multi-signal switching process, so as to meet the control requirements.

[0005] The technical solution provided by the present invention is:

[0006] A multi-signal switching speed limit control system, the control system comprises an input signal switching module (module 1), a switching process rate increase selection module (module 2), a switching process rate reduction selection module (module 3), a rate limit enabling module (module 4), an output signal rate setting and speed limit module (module 5) and an output signal receiving module (module 6), wherein the output end of the input signal switching module is connected to the input end of the output signal rate setting and speed limit module as a signal to be processed without speed limit after signal switching; the output ends of the switching process rate increase selection module and the switching process rate reduction selection module are connected to the input end of the output signal rate setting and speed limit module as the rate limit value of the output increase or decrease of the output of the output signal rate setting and speed limit module during the signal switching process; the output end of the rate limit enabling module is connected to the input end of the output signal rate setting and speed limit module as the basis for the output signal rate setting and speed limit module to determine whether to output speed limit the input end signal; the output end of the output signal rate setting and speed limit module is connected to the input end of the output signal receiving module (module 6) for screen display, signal transmission or control instruction generation, wherein:

[0007] The control system includes an input signal switching module: used to select the signal source of the corresponding channel and output without speed limit, and its output value is input to the output signal rate setting and speed limit module as the signal before speed limit;

[0008] The switching process increasing rate selection module and the switching process decreasing rate selection module are used to select the switching rate in the process of switching to the corresponding channel, which are the increasing rate and the decreasing rate, respectively, so as to limit the speed of signal transmission;

[0009] Rate Limit Enable Module: used to select whether to use the speed limit function for signal transmission, and select speed limit or no speed limit;

[0010] Output signal rate setting and speed limit module: used to judge and process the input signal and then output it. When the speed is limited, the module outputs the value of the signal before the speed limit after the increase and decrease rates are limited. When the speed is not limited, the module directly outputs the signal value before the speed limit.

[0011] Output signal receiving module: used for screen display, signal transmission, control instruction generation or any combination of the above three signals after speed limit judgment and speed limit processing.

[0012] The working principle of the method of the present invention is: if it is not in the signal switching process, the signal of any channel is output from module 1, transmitted through module 5, and output to module 6, and is not subject to rate restrictions. If it is in the signal switching process, taking the signal switching from any channel to channel 2 as an example, the output value of module 5 is based on the current value, the signal value of channel 2 is the target, and the output values ​​of module 2 and module 3 are used as the rising rate limit value and the falling rate limit value respectively. When the output value of module 5 is equal to the signal value of channel 2, the signal switching is completed, and thereafter the signal of channel 2 is not subject to rate restrictions during the change process. Regardless of whether it is in the switching process or not, the output of module 5 is not subject to rate restrictions when it is transmitted to module 6.

[0013] Compared with the prior art, the present invention has the following beneficial technical effects:

[0014] (1) Limiting the speed of the signal switching process with multiple signal sources to make up for the functional defects in the control system is an important functional design in the construction of the control strategy;

[0015] (2) The switching process rate under multiple channels can be set independently to increase the flexibility of switching process rate control;

[0016] (3) This method is built on the basic modules available in all types of control systems, has good engineering applicability, and has strong operability and promotion value. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the connection of the system modules of the present invention.

[0018] Figure 2 The figure is a schematic diagram of building a rate limiting enabling module of the present invention. DETAILED DESCRIPTION

[0019] The specific implementation modes of the present invention are further described in detail below in conjunction with the accompanying drawings.

[0020] like Figure 1 , 2As shown, the present invention provides a multi-signal switching speed limit control system, which includes an input signal switching module (module 1), a switching process rate increase selection module (module 2), a switching process rate reduction selection module (module 3), a rate limit enabling module (module 4), an output signal rate setting and speed limit module (module 5) and an output signal receiving module (module 6), wherein the output end (OP1) of the input signal switching module is connected to the input end (IN1) of the output signal rate setting and speed limit module as a signal to be processed without speed limit after signal switching; the output ends (U1) of the switching process rate increase selection module and the switching process rate reduction selection module are connected to the output signal rate setting and speed limit module. The output terminal (EN) of the rate limit enable module is connected to the input terminal (IN4) of the output signal rate setting and speed limit module, which serves as the basis for the output signal rate setting and speed limit module to determine whether to output the speed limit of its input terminal (IN1); the output terminal (OT) of the output signal rate setting and speed limit module is connected to the input terminal (IN2 and IN3) of the module 6 for screen display, signal transmission or control instruction generation, wherein:

[0021] The control system includes an input signal switching module: used to select the signal source of the corresponding channel and output without speed limit, and its output value is input to the output signal rate setting and speed limit module as the signal before speed limit;

[0022] The switching process increasing rate selection module and the switching process decreasing rate selection module are used to select the switching rate in the process of switching to the corresponding channel, which are the increasing rate and the decreasing rate, respectively, so as to limit the speed of signal transmission;

[0023] Rate Limit Enable Module: used to select whether to use the speed limit function for signal transmission, and select speed limit or no speed limit;

[0024] Output signal rate setting and speed limit module: used to judge and process the input signal and then output it. When the speed is limited, the module outputs the value of the signal before the speed limit after the increase and decrease rates are limited. When the speed is not limited, the module directly outputs the signal value before the speed limit.

[0025] Output signal receiving module: used for screen display, signal transmission, control instruction generation or any combination of the above three signals after speed limit judgment and speed limit processing.

[0026] The multi-signal switching speed limit control system is applied to a control system having the following modules: an "equal" judgment logic block, a "not equal" judgment logic block, an "and" judgment logic block, a "pulse signal generation" logic block, a "set high level signal / reset high level signal" logic block, a switching block that does not limit the speed of the switching process, a rate limiting module that has an enabling function and can be connected, and an output quantity storage module.

[0027] To ensure the use effect, the input signal switching module adopts the existing switching block in the control system without speed limit for the switching process. N groups of signal sources are respectively connected to the N input terminals (PV1, PV2, ..., PVN) of the input signal switching module through N input channels as input signals to be switched; the channel selection signal is manually set by the control panel and connected to the input terminal (S) of the input signal switching module as a channel selection instruction; the output terminal (OP1) of the input signal switching module is used as the switched signal without speed limit.

[0028] The output signal rate setting and speed limit module adopts the rate limit module that can be connected to the existing limit value in the control system. The input terminal IN1 is connected to the input signal before the speed limit, the input terminal IN2 and the input terminal IN3 are respectively connected to the speed increase limit value and the speed decrease limit value when the speed limit operation is executed, and the input terminal IN4 is connected to the rate limit enable signal. The implementation method is:

[0029] (1) When IN4 is 0, OT (N) =IN1 (N)；

[0030] (2) When IN4 is 1 and the value of IN1 increases, if IN1 (N) —IN1 (N-1) ≥IN2_U, OT (N) =OT (N-1) +IN2_U, otherwise OT (N) =IN1 (N) ;

[0031] (3) When IN4 is 1 and the value of IN1 decreases, if IN1 (N-1) —IN1 (N) ≥IN3_D, OT (N) =OT (N-1) —IN3_D, otherwise OT (N) =IN1 (N) ;

[0032] Among them, IN1 (N) and OT (N) are the input value and output value of module 5 at the current moment; IN1 (N-1) and OT (N-1)are the input value and output value of module 5 at the previous moment respectively; IN2_U and IN3_D are the speed increase limit and speed decrease limit received by IN2 and IN3 terminals respectively, converted to the change limit within one operation cycle;

[0033] The input terminal (IN4) in module 5 is connected to the speed limit enable instruction. When the logic of the IN4 terminal is 1, the OT terminal is the output of the IN1 terminal signal after the speed limit is executed; when the logic of the IN4 terminal is 0, the OT terminal directly outputs the IN1 terminal value.

[0034] The switching process rate increase selection module and the switching process rate reduction selection module adopt the existing switching block in the control system without speed limit for the switching process; N rate increase limits are respectively connected to the N input terminals (U1, U2, ..., UN) of the switching process rate increase selection module through N input channels as the rate increase limits to be selected; N rate reduction limits are respectively connected to the N input terminals (D1, D2, ..., DN) of the switching process rate reduction selection module through N input channels as the rate reduction limits to be selected, and the input terminal (S) of the switching process rate increase selection module and the input terminal (S) of the switching process rate reduction selection module receive the same channel selection signal as the input terminal (S) of the input signal switching module. For example: when the channel selection signal is 3, the output terminal (OP1) of the input signal switching module outputs the PV3 terminal value without speed limit, and the output terminal (US) of the switching process rate increase selection module and the output terminal (DS) of the switching process rate reduction selection module respectively output the U3 terminal and D3 terminal values ​​without speed limit.

[0035] The rate limiting enabling module is constructed by combining the existing modules in the control system. The "equal" judgment logic block in the applied control system is represented by the "=" module, the "not equal" judgment logic block is represented by the "!=" module, the "pulse signal generation" logic block is represented by the "pulse n" module, the "and" judgment logic block is represented by the "AND" module, and the "set high level signal / reset high level signal" logic block is represented by the "RS trigger" module;

[0036] The specific construction steps are as follows:

[0037] Step 4-1: Build the "Channel Selection Signal" module as input, and assign the output to the built "Channel Selection Signal (Register)" module;

[0038] Step 4-2: Use the "!=" module to determine whether the outputs of the "channel selection signal" and "channel selection signal (registered)" modules are equal. If the values ​​are the same, the "!=" module outputs 0; otherwise, it outputs 1.

[0039] Step 4-3: Use the "=" module to determine whether the output end (OT) of the output signal rate setting and speed limit module and the output end (OP1) of the input signal switching module are equal. If the values ​​are the same, the "=" module outputs 1, otherwise it outputs 0;

[0040] Step 4-4: Build the "Pulse 1" module, connect the input end of the "Pulse 1" module to the output end of the "!=" module, and set the pulse time parameter of the "Pulse 1" module to 1 scan cycle. The function to be realized is: when the "!=" module outputs 1, the "Pulse 1" module outputs a "1" signal of a pulse time parameter, and a "0" signal after a pulse time parameter;

[0041] Step 4-5: Build the "AND" module, connect the output of the "=" module to the input 1 of the "AND" module, and reserve the input 2 of the "AND" module. The function to be realized is: when the input 1 and input 2 of the "AND" module are both 1, the output of the "AND" module is 1, otherwise it outputs 0;

[0042] Step 4-6: Build the "Pulse 2" module, set the pulse time parameter of the "Pulse 2" module to 1 scan cycle, connect the output of the "AND" module to the input of the "Pulse 2" module, and implement the following function: when the "AND" module outputs 1, the "Pulse 2" module outputs a "1" signal of a pulse time parameter, and a "0" signal after a pulse time parameter;

[0043] Step 4-7: Build the "RS trigger" module, connect the output of the "pulse 1" module to the input S of the "RS trigger" module, connect the output of the "pulse 2" module to the input R of the "RS trigger" module, and connect the output of the "RS trigger" module to the input 2 of the "AND" module and the input of the output signal rate setting and speed limit module (connected to the IN4 of module 5 as the output of module 4); the function to be realized is: when the input S of the "RS trigger" module is 1 and the R terminal is 0, the output terminal of the "RS trigger" outputs a long signal of 1, and the output remains 1 when the S terminal becomes 0; when the R terminal is 1, the output is 0; if both the S terminal and the R terminal are 0, the output remains unchanged;

[0044] The output signal receiving module adopts the existing output quantity register module of the control system, and the register quantity of the output signal receiving module (module 6) can be used for screen display, signal transmission, and control instruction generation.

[0045] The execution order of the output signal rate setting and speed limit module is after the input signal switching module, the switching process rate increase selection module, the switching process rate reduction selection module, and the rate limit enabling module; the execution order of the "channel selection signal (registration)" module in the rate limit enabling module is after the "!=" module.

[0046] The method of the present invention has been implemented in the control system of a 330MW unit, and the specific situation is as follows:

[0047] Unit Overview: The unit adopts a domestically produced control system. So far, all the released versions of the control system do not have a module for speed limiting during multi-signal switching, resulting in the lack of some control logic and large parameter fluctuations during signal switching, which seriously affects the stability of unit operation.

[0048] By adopting this method to design the speed limit function, a total of 26 control functions that require speed limit during signal switching can be realized, which has strong engineering applicability and promotion value.

Claims

1. A multi-signal switching speed limit control system, characterized in that: The control system comprises an input signal switching module, a switching process rate increase selection module, a switching process rate reduction selection module, a rate limit enabling module, an output signal rate setting and speed limit module and an output signal receiving module, wherein the output end of the input signal switching module is connected to the input end of the output signal rate setting and speed limit module as a to-be-processed signal without speed limit after signal switching; the output ends of the switching process rate increase selection module and the switching process rate reduction selection module are connected to the input end of the output signal rate setting and speed limit module as the rate limit value of the output increase or decrease of the output of the output signal rate setting and speed limit module during the signal switching process; the output end of the rate limit enabling module is connected to the input end of the output signal rate setting and speed limit module as the basis for the output signal rate setting and speed limit module to judge whether to perform output speed limit on its input end signal; the output end of the output signal rate setting and speed limit module is connected to the input end of the output signal receiving module for screen display, signal transmission or control instruction generation, wherein: The control system includes an input signal switching module: used to select the signal source of the corresponding channel and output without speed limit, and its output value is input to the output signal rate setting and speed limit module as the signal before speed limit; The switching process increasing rate selection module and the switching process decreasing rate selection module are used to select the switching rate in the process of switching to the corresponding channel, which are the increasing rate and the decreasing rate, respectively, so as to limit the speed of signal transmission; Rate Limit Enable Module: used to select whether to use the speed limit function for signal transmission, and select speed limit or no speed limit; Output signal rate setting and speed limit module: used to judge and process the input signal and then output it. When the speed is limited, the module outputs the value of the signal before the speed limit after the increase and decrease rates are limited. When the speed is not limited, the module directly outputs the signal value before the speed limit. Output signal receiving module: used for screen display, signal transmission, control instruction generation or any combination of the above three signals after speed limit judgment and speed limit processing.

2. A multi-signal switching speed limit control system according to claim 1, characterized in that: The input signal switching module adopts the existing switching block in the control system without speed limit for the switching process. N groups of signal sources are respectively connected to the N input ends of the input signal switching module through N input channels as input signals to be switched; the channel selection signal is set by the control panel and connected to the input end of the input signal switching module as a channel selection instruction; the output end of the input signal switching module is used as a switched signal without speed limit.

3. A multi-signal switching speed limit control system according to claim 1, characterized in that: The switching process rate increase selection module and the switching process rate decrease selection module adopt the existing switching block in the control system that does not limit the speed of the switching process; N rate increase limits are respectively connected to the N input ends of the switching process rate increase selection module through N input channels as the rate increase limits to be selected; N rate decrease limits are respectively connected to the N input ends of the switching process rate decrease selection module through N input channels as the rate decrease limits to be selected, and the input end of the switching process rate increase selection module and the input end of the switching process rate decrease selection module receive the same channel selection signal as the input end of the input signal switching module.

4. A multi-signal switching speed limit control system according to claim 1, characterized in that: The rate limiting enabling module is constructed by combining the existing modules in the control system. The "equal" judgment logic block in the applied control system is represented by the "=" module, the "not equal" judgment logic block is represented by the "!=" module, the "pulse signal generation" logic block is represented by the "pulse n" module, the "and" judgment logic block is represented by the "AND" module, and the "set high level signal / reset high level signal" logic block is represented by the "RS trigger" module; The specific construction steps are as follows: Step 4-1: Build the "Channel Selection Signal" module as input, and assign the output to the built "Channel Selection Signal (Register)" module; Step 4-2: Use the "!=" module to determine whether the outputs of the "channel selection signal" and "channel selection signal (registered)" modules are equal. If the values ​​are the same, the "!=" module outputs 0; otherwise, it outputs 1. Step 4-3: Use the "=" module to determine whether the output values ​​of the output signal rate setting and speed limit module and the output value of the input signal switching module are equal. If the values ​​are the same, the "=" module outputs 1, otherwise it outputs 0; Step 4-4: Build the "Pulse 1" module, connect the input end of the "Pulse 1" module to the output end of the "!=" module, and set the pulse time parameter of the "Pulse 1" module to 1 scan cycle. The function to be realized is: when the "!=" module outputs 1, the "Pulse 1" module outputs a "1" signal of a pulse time parameter, and a "0" signal after a pulse time parameter; Step 4-5: Build an "AND" module, connect the output of the "=" module to the input 1 of the "AND" module, and reserve the input 2 of the "AND" module. The function to be realized is: when both the input 1 and the input 2 of the "AND" module are 1, the output of the "AND" module is 1, otherwise the output is 0; Step 4-6: Build the "Pulse 2" module, set the pulse time parameter of the "Pulse 2" module to 1 scan cycle, and connect the output of the "AND" module to the input of the "Pulse 2" module. The function to be realized is: when the "AND" module outputs 1, the "Pulse 2" module outputs a "1" signal of a pulse time parameter, and a "0" signal after a pulse time parameter; Step 4-7: Build the "RS trigger" module, connect the output of the "Pulse 1" module to the input S of the "RS trigger" module, connect the output of the "Pulse 2" module to the input R of the "RS trigger" module, and connect the output of the "RS trigger" module to the input 2 of the "AND" module and the input of the output signal rate setting and speed limit module respectively. The functions implemented are: when the input S of the "RS trigger" module is 1 and the R terminal is 0, the output of the "RS trigger" outputs a long signal of 1, and the output remains 1 when the S terminal becomes 0; when the R terminal is 1, the output is 0; if both the S terminal and the R terminal are 0, the output remains unchanged.

5. A multi-signal switching speed limit control system according to claim 4, characterized in that: The execution order of the output signal rate setting and rate limit module is after the input signal switching module, the switching process rate increase selection module, the switching process rate reduction selection module, and the rate limit enabling module; the execution order of the "channel selection signal (registration)" module in the rate limit enabling module is after the "!=" module.

6. A multi-signal switching speed limit control system according to claim 1, characterized in that: The output signal rate setting and speed limit module adopts the rate limit module that can be connected to the existing limit value in the control system. The input terminal IN1 is connected to the input signal before the speed limit, the input terminal IN2 and the input terminal IN3 are respectively connected to the speed increase limit value and the speed decrease limit value when the speed limit operation is executed, and the input terminal IN4 is connected to the rate limit enable signal. The implementation method is: (1) When IN4 is 0, OT (N) =IN1 (N) ; (2) When IN4 is 1 and the value of IN1 increases, if IN1 (N) —IN1 (N-1) ≥IN2_U, OT (N) =OT (N-1) +IN2_U, otherwise OT (N) =IN1 (N) ; (3) When IN4 is 1 and the value of IN1 decreases, if IN1 (N-1) —IN1 (N) ≥IN3_D, OT (N) =OT (N-1) —IN3_D, otherwise OT (N) =IN1 (N) ; Among them, IN1 (N) and OT (N) are the input value and output value of module 5 at the current moment; IN1 (N-1) and OT (N-1) are the input value and output value of module 5 at the previous moment respectively; IN2_U and IN3_D are the speed increase limit and speed decrease limit received by IN2 and IN3 terminals respectively, converted to the change limit within one operation cycle.

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