Three-loop cascade control method suitable for multi-input single-output liquid level control system

Abstract

The invention relates to a three-loop cascade control method suitable for a multi-input single-output liquid level control system, which is applied to the technical field of three-waste treatment and comprises the following steps: acquiring system loop information of a target control system and historical control data of system path information; identifying and obtaining a transfer function based on the system loop information and the historical control data; determining a control adjustment parameter of a target loop controller based on the transfer function and the system loop information; and performing liquid level control on the target control system based on the control adjustment parameters. The liquid level control device has the effect of efficiently and stably controlling the liquid level.

Description

Technical Field

[0001] The present application relates to the technical field of three wastes treatment, and in particular to a three-circuit cascade control method suitable for a multi-input single-output liquid level control system. Background Art

[0002] A multiple input single output level control system is an industrial control system used to regulate the liquid level in a container. The system controls a single output signal through multiple input signals to ensure that the liquid level remains within a set range.

[0003] When using conventional PID control, the three-way liquid inlet regulating valve will move frequently and significantly, and the liquid level output oscillation phenomenon is obvious. When the liquid level alarm is triggered, the electromagnetic pneumatic valve will be closed, and the other three regulating valves will not be completely closed although they are adjusted down, causing the liquid level to rise slowly and the system cannot reach a stable state. Summary of the invention

[0004] In order to perform liquid level control efficiently and stably, the present application provides a three-loop cascade control method suitable for a multi-input single-output liquid level control system.

[0005] In the first aspect, the present application provides a three-circuit cascade control method applicable to a multi-input single-output liquid level control system, which adopts the following technical solution:

[0006] A three-loop cascade control method suitable for a multi-input single-output liquid level control system, comprising:

[0007] Acquire system loop information of a target control system and historical control data of the system path information;

[0008] identifying a transfer function based on the system loop information and the historical control data;

[0009] Determining a control adjustment parameter of a target loop controller based on the transfer function and the system loop information;

[0010] The target control system is subjected to liquid level control based on the control adjustment parameter.

[0011] By adopting the above technical scheme, based on the system loop information of the target control system and the historical control data, a transfer function for subsequently calculating the control adjustment parameters is obtained, the transfer function and the system loop information are used to determine the control adjustment parameters of the loop controller of each control loop in the target control system, and the calculated control adjustment parameters are used to control the adjustment status of the control loop controller, so as to achieve the effect of automatic and accurate control of the target control system, thereby realizing efficient and stable liquid level control.

[0012] Optionally, the identifying a transfer function based on the system loop information and the historical control data includes:

[0013] Sort the liquid inlet circuits of the target control system based on the system circuit information to obtain a liquid inlet circuit sequence;

[0014] Obtaining control rules;

[0015] Determining a loop function adjustment order of the liquid inlet loop sequence based on the control rule;

[0016] Determine the regulating valve opening information and circuit liquid level information of the liquid inlet circuit based on the historical control data;

[0017] Based on the loop function adjustment sequence, the regulating valve opening information and the loop liquid level information, identification processing is performed to obtain the transfer function of the liquid inlet loop.

[0018] Optionally, determining the control adjustment parameters of the target loop controller based on the transfer function and the system loop information includes:

[0019] Get the target attenuation rate;

[0020] Calculate the control ratio and control integral of the liquid inlet circuit based on the target attenuation rate and the transfer function;

[0021] Acquiring control accuracy information of the target loop controller;

[0022] The control adjustment parameter of the target loop controller is determined based on the control accuracy information, the control valve opening information, the control ratio and the control integral.

[0023] Optionally, the performing liquid level control on the target control system based on the control adjustment parameter includes:

[0024] Acquiring working environment information of the target control system;

[0025] Determining whether drainage treatment is required based on the working environment information;

[0026] If drainage treatment is required, obtaining control adjustment parameters of the target loop controller;

[0027] The valve opening of the corresponding regulating valve is adjusted based on the target loop controller and the control adjustment parameter.

[0028] Optionally, after performing liquid level control on the target control system based on the control adjustment parameter, the method further includes:

[0029] Obtain liquid level control information and expected control results;

[0030] generating a liquid level control report based on the liquid level control information and the expected control result;

[0031] Binding the liquid level control report with the regulation control parameter to generate regulation control information;

[0032] The adjustment control information is stored in a preset storage module and sent to the mobile terminal of the staff.

[0033] In the second aspect, the present application provides a three-circuit cascade control device suitable for a multi-input single-output liquid level control system, which adopts the following technical solution:

[0034] A three-circuit cascade control device suitable for a multi-input single-output liquid level control system, comprising:

[0035] A historical data acquisition module, used to acquire historical control data of system loop information and system path information of a target control system;

[0036] A transfer function identification module, used for identifying a transfer function based on the system loop information and the historical control data;

[0037] A regulating parameter determining module, used for determining a control regulating parameter of a target loop controller based on the transfer function and the system loop information;

[0038] A liquid level adjustment control module is used to perform liquid level control on the target control system based on the control adjustment parameters.

[0039] By adopting the above technical scheme, based on the system loop information of the target control system and the historical control data, a transfer function for subsequently calculating the control adjustment parameters is obtained, the transfer function and the system loop information are used to determine the control adjustment parameters of the loop controller of each control loop in the target control system, and the calculated control adjustment parameters are used to control the adjustment status of the control loop controller, so as to achieve the effect of automatic and accurate control of the target control system, thereby realizing efficient and stable liquid level control.

[0040] In a third aspect, the present application provides an electronic device, which adopts the following technical solution:

[0041] An electronic device comprises a processor, wherein the processor is coupled to a memory;

[0042] The processor is used to execute the computer program stored in the memory so that the electronic device executes the computer program of the three-loop cascade control method applicable to a multi-input single-output liquid level control system as described in any one of the first aspects.

[0043] In a fourth aspect, the present application provides a computer-readable storage medium, which adopts the following technical solution:

[0044] A computer-readable storage medium stores a computer program that can be loaded by a processor and executes the three-loop cascade control method applicable to a multi-input single-output liquid level control system as described in any one of the first aspects.

[0045] In summary, this application includes the following beneficial technical effects:

[0046] According to the system loop information and historical control data of the target control system, the transfer function used to calculate the control adjustment parameters is obtained. The transfer function and the system loop information are used to determine the control adjustment parameters of the loop controller of each control loop in the target control system. The calculated control adjustment parameters are used to control the adjustment of the loop controller, so as to achieve the effect of automatic and accurate control of the target control system, thereby realizing efficient and stable liquid level control. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a flow chart of a three-loop cascade control method suitable for a multi-input single-output liquid level control system provided in an embodiment of the present application.

[0048] Figure 2 It is a system control flow diagram suitable for a multi-input single-output liquid level control system provided in an embodiment of the present application.

[0049] Figure 3 It is a structural block diagram of a three-loop cascade control device suitable for a multi-input single-output liquid level control system provided in an embodiment of the present application.

[0050] Figure 4 It is a structural block diagram of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0051] The present application is further described in detail below in conjunction with the accompanying drawings.

[0052] The embodiment of the present application provides a three-circuit cascade control method applicable to a multi-input single-output liquid level control system, which can be executed by an electronic device, which can be a server or a terminal device, wherein the server can be an independent physical server, or a server cluster or distributed system composed of multiple physical servers, or a cloud server providing cloud computing services. The terminal device can be a smart phone, a tablet computer, a desktop computer, etc., but is not limited thereto.

[0053] Figure 1A flow chart of a three-loop cascade control method suitable for a multi-input single-output liquid level control system provided in an embodiment of the present application.

[0054] like Figure 1 As shown, the main process of the method is described as follows (steps S101 to S104):

[0055] Step S101, acquiring historical control data of system loop information and system path information of a target control system.

[0056] In this embodiment, the system loop information of the target control system includes the number of system loops, the system control process, the control valve model and the loop controller model, and the correspondence between the control valve and the loop controller, etc. The historical control data of the system path information is, in the target control system, the historical control valve opening information, the historical liquid level information and the correspondence between the two of each loop. It should be noted that the system loop information and historical control data need to be increased according to actual usage requirements, and the specific system loop information and historical control data are not specifically limited here.

[0057] Step S102: obtaining a transfer function based on system loop information and historical control data.

[0058] For step S102, the liquid inlet circuits of the target control system are sorted based on the system loop information to obtain a liquid inlet circuit sequence; the control rules are obtained; the loop function adjustment order of the liquid inlet circuit sequence is determined based on the control rules; the regulating valve opening information and the loop liquid level information of the liquid inlet circuit are determined based on the historical control data; identification processing is performed based on the loop function adjustment order, the regulating valve opening information and the loop liquid level information to obtain the transfer function of the liquid inlet circuit.

[0059] Reference Figure 2In this embodiment, the target control system includes four liquid inlet loops, which are sequentially arranged as the first liquid inlet loop, the second liquid inlet loop and the third liquid inlet loop according to the liquid inlet route from outside to inside, and the loop used for feedforward regulation is used as the fourth liquid inlet loop, thereby obtaining a liquid inlet loop sequence from outside to inside, wherein the first liquid inlet loop is regulated as the main loop, and the first loop controller is set as the main controller; the second liquid inlet loop is regulated as the auxiliary first loop, and the second loop controller is set as the auxiliary first controller; the third liquid inlet loop is regulated as the auxiliary second loop, and the third loop controller is set as the auxiliary second controller; the fourth liquid inlet loop is introduced into the inner loop as an interference quantity for elimination. The control rule is that when making adjustments, adjustments are made from the inside to the outside in sequence, that is, after the third liquid inlet circuit is adjusted, the second and fourth liquid inlet circuits are adjusted, and finally the first liquid inlet circuit is adjusted. When determining the transfer function, it is necessary to ensure that the regulating valve opening and the circuit liquid level of the current liquid inlet circuit are variables, and the regulating valve openings of other liquid inlet circuits remain unchanged, that is, variables and quantitative extraction are performed from the regulating opening information and the circuit liquid level information. For example, when determining the transfer function of the first liquid inlet circuit, the regulating valve openings of the second and third liquid inlet circuits remain unchanged, the regulating valve of the fourth liquid inlet circuit remains open, and the liquid level outlet magnetic pump stops. When the regulating valve opening of the first liquid inlet circuit changes, the liquid level changes, that is, the regulating valve opening of the first liquid inlet circuit is used as the input signal, and the circuit liquid level is used as the output signal. The transfer function of the first liquid inlet affecting the liquid level change is identified. Similarly, the transfer functions of the second, third, and fourth liquid inlet circuits affecting the liquid level change are identified.

[0060] Step S103: determining control adjustment parameters of the target loop controller based on the transfer function and the system loop information.

[0061] For step S103, the target attenuation rate is obtained; the control ratio and control integral of the liquid inlet circuit are calculated based on the target attenuation rate and the transfer function; the control accuracy information of the target loop controller is obtained; and the control adjustment parameters of the target loop controller are determined based on the control accuracy information, the regulating valve opening information, the control ratio and the control integral.

[0062] In this embodiment, the target attenuation rate is set to 0.75, which can make the adjustment more accurate and make it easier to calculate the control ratio and control integral. After setting the target attenuation rate, the transfer function obtained by the above identification is used to calculate the proportion and integral of the PID, and the calculated proportion is used as the control proportion, and the calculated integral is used as the control integral. Since the control precision of different anger table controllers is different, and the opening of the regulating valve is different, the corresponding adjustment control parameters under different control proportions and control integrals are also different. First, the corresponding relationship between the control precision and the opening of the regulating valve is determined according to the preset comparison table, that is, the minimum controller precision is 1.0 and the corresponding opening is 1%. When the controller parameter of the controller is 10, the opening of the regulating valve is 10%, so that the controller parameters of the control can be calculated according to the control ratio and control integral, and the opening of the regulating valve can be obtained according to the controller parameters. The controller parameters and the opening of the regulating valve are bound to obtain the control adjustment parameters of the final target loop controller. It should be noted that one target loop controller corresponds to one control adjustment parameter, and the control adjustment parameters of different target loop controllers may be different, that is, the control adjustment parameters of different target loop controllers need to be calculated separately and executed separately by the corresponding target loop controller.

[0063] Step S104: performing liquid level control on the target control system based on the control adjustment parameters.

[0064] For step S104, the working environment information of the target control system is obtained; based on the working environment information, it is determined whether drainage treatment is required; if drainage treatment is required, the control adjustment parameters of the target loop controller are obtained; based on the target loop controller and the control adjustment parameters, the valve opening of the corresponding control valve is adjusted.

[0065] In this embodiment, in order to reduce the waste of power resources, the working environment information of the target control system is collected in real time to determine the water storage volume of the working environment. After the water storage volume of the working environment reaches the preset water volume threshold, it is determined that drainage treatment is required, and the control adjustment parameters of each target loop controller are determined. According to the target loop controller and the control adjustment parameters, the valve opening of the corresponding regulating valve is adjusted, so that the target control system enters the working state and performs liquid level control with the calculated controller adjustment parameters. It should be noted that when actually working, the system does not work in the order of the system control process, but all the liquid inlet circuits work at the same time, and the system control process is only used for the calculation of the transfer function.

[0066] In this embodiment, liquid level control information and expected control results are obtained; a liquid level control report is generated based on the liquid level control information and the expected control results; the liquid level control report is bound to the adjustment control parameters to generate the adjustment control information; the adjustment control information is stored in a preset storage module and sent to the staff's mobile terminal.

[0067] After a round of liquid level control or a certain period of liquid level control, liquid level control information is collected, that is, the control liquid level data of the liquid level control is determined, and the expected control result under the ideal state is obtained, the liquid level control information and the expected control result are compared to obtain a control report, and the liquid level control report is bound to the adjustment control parameters to obtain the adjustment control information, and the obtained adjustment control information is sent to the staff's mobile terminal and stored in the preset storage module at the same time, so that the staff can quickly determine the current liquid level situation and facilitate subsequent retrieval and reference.

[0068] Figure 3 A structural block diagram of a three-loop cascade control device 200 suitable for a multi-input single-output liquid level control system provided in an embodiment of the application.

[0069] like Figure 3 As shown, the three-circuit cascade control device 200 suitable for a multi-input single-output liquid level control system mainly includes:

[0070] A historical data acquisition module 201 is used to acquire historical control data of system loop information and system path information of a target control system;

[0071] A transfer function identification module 202, used to identify and obtain a transfer function based on system loop information and historical control data;

[0072] The adjustment parameter determination module 203 is used to determine the control adjustment parameters of the target loop controller based on the transfer function and the system loop information;

[0073] The liquid level adjustment control module 204 is used to perform liquid level control on the target control system based on the control adjustment parameters.

[0074] As an optional implementation of this embodiment, the transfer function identification module 202 is specifically used to sort the liquid inlet circuit of the target control system based on the system loop information to obtain a liquid inlet circuit sequence; obtain control rules; determine the loop function adjustment order of the liquid inlet circuit sequence based on the control rules; determine the regulating valve opening information and loop liquid level information of the liquid inlet circuit based on historical control data; perform identification processing based on the loop function adjustment order, regulating valve opening information and loop liquid level information to obtain the transfer function of the liquid inlet circuit.

[0075] As an optional implementation of this embodiment, the adjustment parameter determination module 203 is specifically used to obtain the target attenuation rate; calculate the control ratio and control integral of the liquid inlet circuit based on the target attenuation rate and the transfer function; obtain the control accuracy information of the target loop controller; and determine the control adjustment parameters of the target loop controller based on the control accuracy information, the regulating valve opening information, the control ratio and the control integral.

[0076] As an optional implementation of this embodiment, the liquid level regulation control module 204 is specifically used to obtain the working environment information of the target control system; determine whether drainage treatment is required based on the working environment information; if drainage treatment is required, obtain the control adjustment parameters of the target loop controller; and adjust the valve opening of the corresponding regulating valve based on the target loop controller and the control adjustment parameters.

[0077] As an optional implementation of this embodiment, the three-circuit cascade control device 200 applicable to a multi-input single-output liquid level control system further includes:

[0078] A control information acquisition module is used to obtain liquid level control information and estimated control results;

[0079] A control report generation module, used for generating a liquid level control report based on liquid level control information and expected control results;

[0080] The adjustment information generation module is used to bind the liquid level control report with the adjustment control parameters to generate the adjustment control information;

[0081] The adjustment information sending module is used to store the adjustment control information in a preset storage module and send it to the mobile terminal of the staff.

[0082] In one example, the module in any of the above devices can be one or more integrated circuits configured to implement the above methods, such as: one or more application specific integrated circuits (ASICs), or, one or more digital signal processors (DSPs), or, one or more field programmable gate arrays (FPGAs), or a combination of at least two of these integrated circuit forms.

[0083] For another example, when the modules in the device can be implemented in the form of a processing element scheduling program, the processing element can be a general-purpose processor, such as a central processing unit (CPU) or other processor that can call a program. For another example, these modules can be integrated together and implemented in the form of a system-on-a-chip (SOC).

[0084] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0085] Figure 4 This is a structural block diagram of an electronic device 300 provided in an embodiment of the present application.

[0086] like Figure 4 As shown, the electronic device 300 includes a processor 301 and a memory 302 , and may further include an information input / information output (I / O) interface 303 , one or more of a communication component 304 , and a communication bus 305 .

[0087] The processor 301 is used to control the overall operation of the electronic device 300 to complete all or part of the steps of the three-loop cascade control method for a multi-input single-output liquid level control system; the memory 302 is used to store various types of data to support the operation of the electronic device 300, and these data may include, for example, instructions for any application or method used to operate on the electronic device 300, and data related to the application. The memory 302 can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (Static Random Access Memory, SRAM), electrically erasable programmable read-only memory (Electrically Erasable Programmable Read-Only Memory, EEPROM), erasable programmable read-only memory (Erasable Programmable Read-Only Memory, EPROM), programmable read-only memory (Programmable Read-Only Memory, PROM), read-only memory (Read-Only Memory, ROM), magnetic memory, flash memory, magnetic disk or optical disk.

[0088] The I / O interface 303 provides an interface between the processor 301 and other interface modules, and the above-mentioned other interface modules can be keyboards, mice, buttons, etc. These buttons can be virtual buttons or physical buttons. The communication component 304 is used for wired or wireless communication between the electronic device 300 and other devices. Wireless communication, such as Wi-Fi, Bluetooth, Near Field Communication (NFC), 2G, 3G or 4G, or a combination of one or more of them, so the corresponding communication component 104 can include: Wi-Fi components, Bluetooth components, NFC components.

[0089] The electronic device 300 can be implemented by one or more application specific integrated circuits (ASIC), digital signal processors (DSP), digital signal processing devices (DSPD), programmable logic devices (PLD), field programmable gate arrays (FPGA), controllers, microcontrollers, microprocessors or other electronic components to execute the three-loop cascade control method for a multi-input single-output liquid level control system given in the above embodiment.

[0090] The communication bus 305 may include a path to transmit information between the above components. The communication bus 305 may be a PCI (Peripheral Component Interconnect) bus or an EISA (Extended Industry Standard Architecture) bus, etc. The communication bus 305 may be divided into an address bus, a data bus, a control bus, etc.

[0091] The electronic device 300 may include, but is not limited to, mobile terminals such as mobile phones, laptop computers, digital broadcast receivers, PDAs (personal digital assistants), PADs (tablet computers), PMPs (portable multimedia players), vehicle-mounted terminals (such as vehicle-mounted navigation terminals), etc., and fixed terminals such as digital TVs, desktop computers, etc., and may also be servers, etc.

[0092] The present application also provides a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above-mentioned three-loop cascade control method applicable to a multi-input single-output liquid level control system are implemented.

[0093] The computer-readable storage medium may include: a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes.

[0094] The terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, article, or apparatus.

[0095] The above description is only a preferred embodiment of the present application and an explanation of the technical principles used. Those skilled in the art should understand that the scope of application involved in the present application is not limited to the technical solution formed by a specific combination of the above technical features, but should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the aforementioned application concept. For example, the above features are replaced with (but not limited to) technical features with similar functions applied in the present application.

Claims

1. A three-circuit cascade control method suitable for a multi-input single-output liquid level control system, characterized in that: include: Acquire system loop information of a target control system and historical control data of the system path information; identifying a transfer function based on the system loop information and the historical control data; Determining a control adjustment parameter of a target loop controller based on the transfer function and the system loop information; The target control system is subjected to liquid level control based on the control adjustment parameter.

2. The method according to claim 1, characterized in that: The identifying and obtaining the transfer function based on the system loop information and the historical control data comprises: Sort the liquid inlet circuits of the target control system based on the system circuit information to obtain a liquid inlet circuit sequence; Obtaining control rules; Determining a loop function adjustment order of the liquid inlet loop sequence based on the control rule; Determine the regulating valve opening information and circuit liquid level information of the liquid inlet circuit based on the historical control data; Based on the loop function adjustment sequence, the regulating valve opening information and the loop liquid level information, identification processing is performed to obtain the transfer function of the liquid inlet loop.

3. The method according to claim 2, characterized in that Determining the control adjustment parameters of the target loop controller based on the transfer function and the system loop information includes: Get the target attenuation rate; Calculate the control ratio and control integral of the liquid inlet circuit based on the target attenuation rate and the transfer function; Acquiring control accuracy information of the target loop controller; The control adjustment parameter of the target loop controller is determined based on the control accuracy information, the control valve opening information, the control ratio and the control integral.

4. The method according to claim 1, characterized in that The performing liquid level control on the target control system based on the control adjustment parameter comprises: Acquiring working environment information of the target control system; Determining whether drainage treatment is required based on the working environment information; If drainage treatment is required, obtaining control adjustment parameters of the target loop controller; The valve opening of the corresponding regulating valve is adjusted based on the target loop controller and the control adjustment parameter.

5. The method according to claim 1, characterized in that After the target control system is subjected to liquid level control based on the control adjustment parameter, the method further includes: Obtain liquid level control information and expected control results; generating a liquid level control report based on the liquid level control information and the expected control result; Binding the liquid level control report with the regulation control parameter to generate regulation control information; The adjustment control information is stored in a preset storage module and sent to the mobile terminal of the staff.

6. A three-circuit cascade control device suitable for a multi-input single-output liquid level control system, characterized in that: include: A historical data acquisition module, used to acquire historical control data of system loop information and system path information of a target control system; A transfer function identification module, used for identifying a transfer function based on the system loop information and the historical control data; A regulating parameter determining module, used for determining a control regulating parameter of a target loop controller based on the transfer function and the system loop information; A liquid level adjustment control module is used to perform liquid level control on the target control system based on the control adjustment parameters.

7. An electronic device, characterized in that: comprising a processor coupled to a memory; The processor is configured to execute a computer program stored in the memory, so that the electronic device executes the method according to any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that: The method comprises a computer program or an instruction, which, when executed on a computer, causes the computer to execute the method according to any one of claims 1 to 5.

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