Interface logic and operating method of artificial intelligence control intervening in traditional analog quantity PID control system in a way of modifying set value

Abstract

This invention relates to the field of thermal automatic control technology, specifically to an interface logic and operation method for artificial intelligence control to intervene in a traditional analog PID control system by modifying setpoints. Addressing the lack of intelligent control interfaces in existing PID control systems, the setpoint function block is improved by adding IC, OTI, OTA, TI, TA, and A / I terminals to realize manual, automatic, and intelligent control modes and their switching logic. In manual mode, the automatic and intelligent control setpoints track feedback values; in automatic mode, the operator's setpoint is valid, and the intelligent control setpoint tracks the automatic setpoint; in intelligent control mode, the artificial intelligence control generates control by adjusting the PID control system setpoint, and the automatic setpoint tracks the intelligent control setpoint. The control mode priority is manual over automatic over intelligent control, with tracking-free switching and state self-holding functions. This invention has strong compatibility, providing support for artificial intelligence control to simulate operator operation and achieve self-cruising adaptive control.

Description

Technical Field

[0001] This invention relates to the field of thermal automatic control technology, specifically to an interface logic and operation method for artificial intelligence control to intervene in a traditional analog PID control system by modifying setpoints. Background Technology

[0002] In recent years, AI (Artificial Intelligence) technology has developed rapidly, and its application areas have continued to expand and penetrate into various industries. Digitalization and intelligentization have become the main driving forces for the development and progress of various industries. In the field of industrial automation, how to improve efficiency, reduce costs, and save manpower by introducing artificial intelligence control is also a current research hotspot.

[0003] Traditional PID negative feedback control dominates the field of analog automatic control. In most cases, existing PID control, or feedforward-feedback composite control, cascade control, and correction control systems based on PID control, can meet practical requirements. A mature overall framework for analog control systems has been established, including: M / A (manual / automatic) station, PID controller, setpoint function block, manual / automatic switching logic, PID controller output and setpoint signal tracking logic, and corresponding user-friendly interfaces. Meanwhile, field operators have become accustomed to monitoring the control system's operating status by observing the values ​​and deviations of SP (setpoint) and PV (feedback value), and CO (controller output) and AF (actuator position feedback) values ​​and deviations, as well as modifying the setpoint in automatic mode and directly adjusting the controller output in manual mode. This control logic and operating method, proven through long-term application, has its engineering rationale and is unlikely to be replaced for a considerable period.

[0004] While existing analog PID control systems can meet field requirements in most cases, special situations such as strong disturbances, strong nonlinearity, and changes in the characteristics of the control objective and the controlled object due to varying operating conditions still require operators to make comprehensive judgments and intervene manually to assist the control system in coping with these special circumstances. The most common intervention method is adjusting the control system's setpoints. For example, in coal-fired power plants, during load changes, operators frequently adjust the setpoints of controlled variables such as superheated / reheat steam temperature, main steam pressure, and superheat degree to help the automatic control system eliminate disturbances and reduce fluctuations in fuel quantity and feedwater flow. They may also modify the setpoint of the controlled variable of flue gas oxygen content to achieve a balance between boiler efficiency and NOx generation. During the start-up / shutdown of coal mills, they may modify the setpoint of the coal feeder's feed rate instruction bias value in the fuel quantity control system to balance the load of each coal mill, and so on. Through the cooperation between humans and the automatic control system, overall control performance is improved, and the expected control objectives are achieved.

[0005] Essentially, artificial intelligence (AI) control should not replace low-level, basic PID control. Instead, it needs to mimic the thinking and operating methods of operators, intervening in existing control systems from a global and higher level. This allows existing control systems to better cope with various changing situations, achieving adaptive, self-learning, self-optimizing, and self-cruising control, gradually reducing the workload of operators in monitoring and operation, until it partially or completely replaces operators. The main challenges currently facing AI are how to integrate it into traditional PID control systems, how to design its logic interface, how to interact with operators, and how to maintain compatibility with existing control systems. Summary of the Invention

[0006] The purpose of this invention is to provide an interface logic and operation method for artificial intelligence control to intervene in a traditional analog PID control system by modifying setpoints, thereby solving the problems in the prior art.

[0007] This invention is achieved through the following technical solution:

[0008] In a first aspect, embodiments of the present invention provide an interface logic and operation method for artificial intelligence control to intervene in a traditional analog PID control system by modifying setpoints. This includes improving the setpoint function block of the original analog PID control system to form an improved setpoint function block. The improved setpoint function block adds the following input / output terminals to the original setpoint function block:

[0009] The intelligent control setting IC is defined as an analog input / output type signal, which is connected to the set value signal given by the artificial intelligence control.

[0010] The operator-controlled intelligent control OTI terminal is defined as an input / output type switch quantity, which is connected to the signal given by the operator station to activate the intelligent control mode;

[0011] The operator exits the intelligent control OTA terminal, defined as an input / output type switch quantity, and is connected to the signal given by the operator station to exit the intelligent control mode;

[0012] The logic is forcibly applied to the intelligent control TI terminal, defined as an input type switch quantity, which is connected to the signal generated by the control logic to forcibly apply the intelligent control mode and exit the normal automatic control mode.

[0013] The logic forces the input to the conventional automatic TA terminal, which is defined as an input type switch quantity and connected to the signal generated by the control logic that forces the exit of intelligent control mode and the entry into conventional automatic control.

[0014] The control mode indicator A / I terminal is defined as an output type switch quantity, used to indicate whether the control mode is automatic or intelligent. When the output is TRUE, it is automatic mode, and when it is FALSE, it is intelligent mode.

[0015] Preferably, in manual mode, the improved setpoint function block outputs the setpoint, automatic setpoint, and intelligent control setpoint while simultaneously tracking the feedback value of the traditional analog PID control system. This is achieved through three analog signal switching logic blocks. When the tracking logic valid TS terminal input is TRUE, the setpoint output SP terminal switches from the non-manual setpoint to the value input at the tracking signal TR terminal; the operator setting OA terminal switches to output mode and connects to the value input at the tracking signal TR terminal; the intelligent control setting IC terminal switches to output mode and connects to the value input at the tracking signal TR terminal; simultaneously, the control mode indicator A / I terminal output remains unchanged.

[0016] Preferably, in automatic mode, the improved setpoint function block outputs the operator setpoint and the intelligent control setpoint tracks the automatic setpoint: this is achieved through two analog signal switching logic blocks. When the logic for forced exit of intelligent control TA terminal input is TRUE or the operator exit of intelligent control OTA terminal input is TRUE, and the tracking logic valid TS terminal input is FALSE, the input of the switching logic block connected to the non-manual setpoint is switched from the intelligent control setpoint IC terminal input to the operator setpoint OA terminal input; the operator setpoint OA terminal switches to input mode and receives communication signals from the operator station; the intelligent control setpoint IC terminal remains in output mode and connects to the value input from the operator setpoint OA terminal; at the same time, the control mode indicator A / I terminal output is set to TRUE.

[0017] Preferably, in the intelligent control mode, the improved setpoint function block outputs the intelligent control setpoint at the SP terminal and automatically tracks the intelligent control setpoint: this is achieved through two analog signal switching logic blocks. When the input of the logic for forced deactivation of intelligent control at the TA terminal is FALSE and the input of the logic for forced activation of intelligent control at the TI terminal is TRUE, or the input of the operator deactivation of intelligent control at the OTA terminal is FALSE and the input of the operator activation of intelligent control at the OTI terminal is TRUE, and the input of the tracking logic valid at the TS terminal is FALSE, the input of the SP terminal output connected to the switching logic block of the non-manual setpoint is switched from the input of the operator setting OA terminal to the input of the intelligent control setpoint IC terminal; the operator setting OA terminal remains in output mode and is connected to the value input of the intelligent control setpoint IC terminal; the intelligent control setpoint IC terminal switches to input mode and receives communication signals from the intelligent control station; at the same time, the output of the control mode indicator A / I terminal is set to FALSE.

[0018] Preferably, the priority order of control mode is manual over automatic and intelligent control: it is achieved by the arrangement order of analog signal switching logic blocks connected to the set value output SP terminal. The analog signal switching logic block connected to the tracking logic valid TS terminal is placed last. When the tracking logic valid TS terminal input is TRUE, the control system is in manual mode regardless of the input value of the logic strong deactivation intelligent control TA terminal or the logic strong activation intelligent control TI terminal.

[0019] Preferably, the control mode priority is automatically greater than the intelligent control mode: This is achieved through a reset-priority RS flip-flop. When the input of the logic for forced intelligent control TA terminal is TRUE or the input of the operator's intelligent control OTA terminal is TRUE, the RS flip-flop reset terminal is TRUE, and the input of the switching logic block connecting the SP terminal output to the non-manual terminal setting value is switched from the intelligent control setting IC terminal input to the operator setting OA terminal input. When the input of the logic for forced intelligent control TA terminal is FALSE and the input of the logic for forced intelligent control TI terminal is TRUE, or the input of the operator's intelligent control OTA terminal is FALSE and the input of the operator's intelligent control OTI terminal is TRUE, and the input of the tracking logic valid TS terminal is FALSE, the RS flip-flop set terminal is TRUE, and the input of the switching logic block connecting the SP terminal output to the non-manual terminal setting value is switched from the operator setting OA terminal input to the intelligent control setting IC terminal input.

[0020] Preferably, the control mode is self-holding: This is achieved through an RS trigger. When the logic forcibly switches to automatic TA or the operator cancels intelligent control OTA, or the logic forcibly switches to intelligent control TI or the operator switches to intelligent control OTI, and the control system is switched to the corresponding automatic or intelligent control mode, even if the input changes to FALSE at the next moment, the control mode will still maintain the automatic or intelligent control mode of the previous moment.

[0021] Preferably, the storage type and signal communication method of the input / output type variables of the improved setpoint function block are as follows: When the control logic of the artificial intelligence control system and the traditional analog control system are in the same control unit, the input / output type variables connected to the intelligent control setting IC, operator intelligent control OTI, and operator intelligent control OTA terminals of the improved setpoint function block are defined as readable and writable global variables; when the control logic of the artificial intelligence control system and the traditional analog control system are not in the same control unit, an OPC-UA communication server is configured for the control unit where the improved setpoint function block is located, and the input / output type quantities connected to the IC, OTI, and OTA terminals are added to the communication list and configured as readable and writable. Then, an OPC-UA communication client is configured in the control unit where the artificial intelligence control system is located for calling.

[0022] Preferably, the operation panel of the original analog PID control system is improved by adding the following buttons and display signals:

[0023] The IM button is used to activate the intelligent control mode. When the operator presses it, the control system will be activated to intelligent control mode. At the same time, the IM button will trigger a press / release action.

[0024] The AM button is used to exit the intelligent control mode. When the operator presses it, the control system exits the intelligent control mode, and the AM button triggers a press / release action.

[0025] The IM button, when clicked, connects the operator to the intelligent control OTI input terminal of the variable connection improvement setting value function block. The red or pink background indicates the TRUE status of the A / I output. The AM button, when clicked, connects the operator to the intelligent control OTA input terminal of the variable connection improvement setting value function block. The green or blue background indicates the FALSE status of the A / I output. The default background color for both the IM and AM buttons is gray.

[0026] The number displayed after IS is the intelligent control setting value signal, and the variable is connected to the intelligent control setting IC input / output terminal of the setting value function block.

[0027] Preferably, the logical function corresponding to the operator's intelligent control mode is as follows: the operator sets the input of the operator's intelligent control OTI terminal to TRUE, thereby switching the control mode to intelligent control; the operator sets the variable connected to the operator's intelligent control OTA terminal to TRUE, thereby switching the control system to automatic mode; the operation effect and priority order of the operator's intelligent control OTI and intelligent control OTA terminals correspond to the inputs of the logical strong intelligent control TI and strong intelligent control TA terminals, respectively. OTI and TI are logically ORed, and OTA and TA are logically ORed. The difference is that the OTI and OTA terminals are connected to input / output variables. When the input becomes TRUE at a certain moment, the setpoint module will rewrite it to FALSE at the next moment after processing the signal to adapt to the operation mode of clicking buttons on the operation panel.

[0028] Preferably, the upper-level artificial intelligence control system achieves the following control functions by adjusting the setpoints of the lower-level analog PID control system:

[0029] Calculate the optimal setpoint or planned setpoint change curve based on the equipment's operating status, and adapt to self-learning, self-adaptation, self-optimization, and self-cruise control functions;

[0030] The analog PID control system is used as a sub-loop, and the main loop, feedforward loop or decoupling loop is built in the artificial intelligence control system to adapt to the macroscopic intelligent cascade control, feedforward feedback composite control and decoupling control functions.

[0031] Within a certain range, the set value is made to follow the change of the feedback value, forming an equivalent control dead zone, so that the PID control output remains unchanged, and the self-holding function is realized under fault and special working conditions.

[0032] The setpoint is based on the feedback value with a fixed bias, so that the PID control output moves in a determined direction and speed, which is equivalent to manually adjusting the position of the actuator and realizing the override control function under fault and special working conditions.

[0033] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0034] This invention proposes an artificial intelligence (AI) control method that intervenes in the interface logic and operation of a traditional analog PID control system by modifying setpoints. This provides effective support for AI control to simulate human operation, enabling the control system to achieve high performance, self-cruising, and adaptive operation. The improved setpoint function block has clear physical meanings for each input and output signal, and the control logic is well-organized, making it easy for technicians to understand and apply. While fully compatible with the original functions of the analog PID control system, an AI control logic interface is added, facilitating system upgrades and modifications. Attached Figure Description

[0035] To more clearly illustrate the technical solutions of the exemplary embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention and should not be considered as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort. In the drawings:

[0036] Figure 1 This is a schematic diagram of the manual control hierarchy provided by the present invention;

[0037] Figure 2 This is a schematic diagram of the hierarchical structure of the automatic control system provided by the present invention;

[0038] Figure 3 This is a schematic diagram of the hierarchical structure of the intelligent control system provided by the present invention;

[0039] Figure 4 This is a schematic diagram of the input / output structure of the setpoint function block in an existing analog PID control system provided by the present invention.

[0040] Figure 5 This is a schematic diagram of the operation panel of an existing analog PID control system provided by the present invention;

[0041] Figure 6 A schematic diagram of the input / output structure of the setpoint function block of the improved analog PID control system provided by the present invention;

[0042] Figure 7 This is a schematic diagram of the operation panel of the improved analog PID control system provided by the present invention. Detailed Implementation

[0043] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0044] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising..." does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes said element.

[0045] It should be noted that all actions involving the acquisition of signals, information, or data in this invention are carried out in compliance with the relevant data protection laws and regulations of the locality and with authorization from the owner of the relevant device.

[0046] Example 1

[0047] The manual control hierarchy in the prior art is as follows: Figure 1 As shown. The operator makes a comprehensive judgment based on various situations and manually operates the actuator to make the controlled variable reach the desired value. In the control configuration logic, only the M (manual operation) station module is needed.

[0048] The existing hierarchical structure of analog PID automatic control systems is as follows: Figure 2 As shown. Compared to manual control, the operator only needs to provide the setpoint according to the expectation, and the control system will automatically adjust the output of the actuator to make the controlled variable reach the setpoint. In the control logic, the M station needs to be transformed into an M / A (manual / automatic switching) station module. In addition, a PID controller, setpoint feedback value deviation calculation, setpoint A module, as well as the corresponding PID controller and setpoint tracking logic, and manual / automatic switching logic need to be added.

[0049] A hierarchical structure of an intelligent control system, such as Figure 3 As shown. Compared to automatic control, its setpoint is given by the intelligent control layer. In the control logic, the setpoint station A needs to be transformed into an A / I (automatic / intelligent control switching) station module. In addition, an intelligent control IC module and corresponding IC controller / setpoint tracking logic and automatic / intelligent control switching logic need to be added.

[0050] The core of this invention is to modify the setpoint A station of the original analog PID control system to upgrade it to an A / I (automatic / intelligent control switching) station, and at the same time design an operation mode and operation screen that are compatible with its control mode.

[0051] For the upper intelligent control layer, the following control effects can be achieved by adjusting the setpoint of the lower analog PID automatic control layer: (1) Calculate the optimal setpoint or plan the setpoint change curve directly according to the equipment operating status, and adapt to self-learning, self-adaptation, self-optimization and self-cruise control functions. (2) Use the analog PID control system as a sub-loop, and build the main loop, feedforward loop or decoupling loop in the artificial intelligence control system to adapt to the macroscopic intelligent cascade control, feedforward feedback composite control and decoupling control functions. (3) Make the setpoint follow the feedback value within a certain range, which can form an equivalent control dead zone, so that the PID control output remains unchanged and realize the self-holding function under fault and special working conditions. (4) Add a fixed bias to the setpoint on the basis of the feedback value, so that the PID control output can act in a determined direction and speed, which is equivalent to manually adjusting the position of the actuator and realizing the override control function under fault and special working conditions.

[0052] In existing DCS (Distributed Control Systems) and PLCs (Programmable Logic Controllers), analog setpoints are generated through setpoint function blocks, and their structure and operation are basically the same. The input / output structure of existing setpoint function blocks is as follows: Figure 4 As shown. Figure 4 In the diagram: the OA terminal is an analog input / output terminal, connected to the analog signal set by the operator; the TR terminal is an analog input terminal, connected to the setpoint tracking signal; the TS terminal is a digital input terminal, connected to the setpoint tracking logic valid signal; and the SP terminal is an analog output terminal, outputting the setpoint of the automatic control system.

[0053] In an analog PID control system, the tracking logic valid signal TS in the existing setpoint function block is associated with the manual / automatic status signal output by the M / A station. When the system switches to manual mode, TS becomes TRUE, causing the function block output signal SP to track the TR input value. The tracking signal TR in the existing setpoint function block should be connected to the control system feedback value.

[0054] The existing analog PID setpoint function block has the following functions:

[0055] (1) Setpoint tracking feedback value in manual mode. When the control system is in manual mode, the tracking logic valid signal TS terminal input will be TRUE. At this time, the setpoint function block is in manual mode, the setpoint SP terminal outputs the value input by the tracking signal TR terminal, and at the same time the operator setting signal OA terminal also outputs the value input by the tracking signal TR terminal, thus realizing the function of setpoint tracking feedback value.

[0056] (2) In automatic mode, the setpoint is set by the operator. When the control system is in automatic mode, the tracking logic valid signal TS terminal input will be FALSE. At this time, the function block receives the value set by the operator station through the OA terminal and outputs it to the SP terminal. Since the operator's operation of modifying the setpoint is a random and discontinuous event, the variable at the OA terminal in automatic mode also has a self-holding function, that is, if the operator does not modify it, the original value remains unchanged.

[0057] The operation panel associated with the existing setting function block is shown in Figure 5. Figure 5 In the control panel: Button A is the automatic function key. When pressed by the operator, the control system enters automatic control mode, and button A is displayed with a red background. Button M is the manual function key. When pressed by the operator, the control system enters manual control mode, and button M is displayed with a green background. Buttons SP+ and SP- are effective in automatic mode. When pressed by the operator, the setpoint SP is increased or decreased in increments. Buttons O+ and O- are effective in manual mode. When pressed by the operator, the controller output O is increased or decreased in increments. On the control panel, the number displayed after SP is the control setpoint signal, which can be directly modified by the operator or modified via buttons SP+ and SP-. It connects to the OA input / output terminal of the setpoint function block. The number displayed after PV is the feedback signal. The number displayed after O is the controller output signal, which can be directly modified by the operator or modified via buttons O+ and O-. The number displayed after F is the actuator position feedback signal. All signal values ​​are represented by star symbols.

[0058] Figure 5 In this document, the functions of buttons A, M, O+, and O-, as well as the displayed O and F signal values, all correspond to the M / A station in the existing analog PID control system. Since the control logic and operation method under the artificial intelligence control mode have not been changed, they will not be described in detail here.

[0059] Existing analog PID control systems include automatic and manual control modes. With the introduction of artificial intelligence control, an intelligent control mode is added. In intelligent control mode, the setpoints of the original analog PID control system are not given by the operator, but rather by the artificial intelligence control system.

[0060] The improved analog setpoint function block input / output structure, compatible with existing control systems, is as follows: Figure 6 As shown. Figure 6The added inputs and outputs in the functional block shown include: the intelligent control setting IC terminal is an analog input / output type, connected to the setpoint signal given by the artificial intelligence control; the operator activates intelligent control OTI terminal is a digital input / output type, connected to the signal given by the operator to activate intelligent control mode; the operator deactivates intelligent control OTA terminal is a digital input / output type, connected to the signal given by the operator to deactivate intelligent control mode; the logic forces intelligent control TI terminal is an input type digital input, connected to the signal generated by the control logic to force intelligent control mode activation; the logic forces intelligent control deactivation TA terminal is an input type digital input, connected to the signal generated by the control logic to force intelligent control mode deactivation; and the control mode indicator A / I terminal is an output type digital input, used to indicate whether the control mode is automatic or intelligent control mode, TRUE for automatic mode and FALSE for intelligent control mode.

[0061] The implemented functions include:

[0062] (1) Setpoint tracking in manual mode. When the tracking logic valid TS terminal input is TRUE, the setpoint output SP terminal outputs the value input at the TR terminal, and both the operator setting OA terminal and the intelligent control setting IC terminal output the value input at the tracking signal TR terminal, realizing the function of automatic and intelligent control setpoint tracking of traditional analog PID feedback value in manual mode. At the same time, the output of the control mode indicator A / I terminal remains unchanged from the previous moment.

[0063] (2) In automatic mode, the operator setting value and the intelligent control setting value are tracked by the automatic setting value. When the tracking logic valid TS terminal input is FALSE and the logic strong exit intelligent control TA terminal input is TRUE, the setting value output SP terminal outputs the operator setting value input at the operator setting OA terminal, and the intelligent control setting IC terminal also outputs the operator setting value input at the OA terminal, realizing the function of the operator setting the automatic setting value and the intelligent control setting value tracking the automatic setting value in automatic mode. At the same time, the control mode indicator A / I terminal output is TRUE.

[0064] (3) In intelligent control mode, the intelligent control setpoint is output and the automatic setpoint tracks the intelligent control setpoint. When the inputs of the tracking logic valid TS terminal and the logic forced intelligent control TA terminal are both FALSE and the logic forced intelligent control TI terminal input is TRUE, the setpoint output SP terminal outputs the setpoint of the IC terminal intelligent control, and the operator setting OA terminal also outputs the setpoint of the IC terminal intelligent control, realizing the function of outputting the setpoint set by artificial intelligence control and the automatic setpoint tracking the intelligent control setpoint in intelligent control mode. At the same time, the control mode indicator A / I terminal outputs FALSE.

[0065] (4) The control mode priority from high to low is manual, automatic, and intelligent control. When the tracking logic valid TS terminal input is TRUE, the control system is in manual mode regardless of the input values ​​of the logic forced exit intelligent control TA terminal and the logic forced start intelligent control TI terminal. When the tracking logic valid TS terminal input is FALSE and the logic forced exit intelligent control TA terminal input is TRUE, the control system is in automatic mode regardless of the input value of the logic forced start intelligent control TI terminal. Only when the tracking logic valid TS terminal input is FALSE, the logic forced exit intelligent control TA terminal input is FALSE, and the logic forced start intelligent control TI terminal input is TRUE can the control system be put into intelligent control mode.

[0066] (5) Operator-activated / deactivated intelligent control mode function. The operator activates the intelligent control mode by setting the input of the Operator-activated Intelligent Control OTI terminal to TRUE; and activates the automatic control mode by setting the variable connected to the Operator-deactivated Intelligent Control OTA terminal to TRUE. The operation effects and priorities of the Operator-activated Intelligent Control OTI and Operator-deactivated Intelligent Control OTA terminals correspond to the logical forced activation Intelligent Control TI and forced deactivation Intelligent Control TA terminals, respectively. OTI and TI are logically ORed, and OTA and TA are logically ORed. The difference lies in the fact that the OTI and OTA terminals are connected to input / output variables. When the input becomes TRUE at a certain moment, the setpoint module will rewrite it to FALSE at the next moment after processing the signal to adapt to the operation mode of clicking buttons on the operation panel.

[0067] (6) Control mode self-holding function. When the logic forcibly switches to automatic TA or the operator cancels intelligent control OTA, the logic forcibly switches to intelligent control TI or the operator switches to intelligent control OTI, and the control system is switched to the corresponding automatic or intelligent control mode, the control mode will still be maintained even if the input changes to FALSE at the next moment.

[0068] The operation panel associated with the Improved Settings function block is shown in Figure 7. Figure 7 The added buttons and display signals include: Button IM is for activating intelligent control mode; pressing it activates the intelligent control mode. Button AM is for deactivating intelligent control mode; pressing it deactivates the intelligent control mode. The IM button's input is connected to the operator-activated intelligent control OTI input terminal of the improved setpoint function block; a red or pink background indicates the TRUE status of the A / I output. The AM button's input is connected to the operator-deactivated intelligent control OTA input terminal of the improved setpoint function block; a green or blue background indicates the FALSE status of the A / I output. The default background color for both buttons IM and AM is gray. The number displayed after IS is the intelligent control setpoint signal, connected to the intelligent control setting IC input / output terminal of the improved setpoint function block.

[0069] The preferred embodiment of this invention is as follows: Function blocks (FBs) are developed and encapsulated using industrial programming languages ​​such as ST (Structured Text), LD (Ladder Diagram), or general-purpose programming languages ​​such as C++, C#, etc., and then invoked when configuring the corresponding control logic and screen in a DCS or PLC. Specific implementation steps include:

[0070] 1. Write program code to improve the setpoint function block and implement:

[0071] (1) Improve the setpoint function block of the original analog PID control system. Add the following to the original setpoint function block: Figure 6 The input / output terminals shown include: Intelligent Control Setting IC terminal, defined as an analog input / output signal, connected to the setpoint signal given by the artificial intelligence control; Operator Intelligent Control On (OTI) terminal, defined as a digital input / output signal, connected to the signal given by the operator to activate intelligent control mode; Operator Intelligent Control Off (OTA) terminal, defined as a digital input / output signal, connected to the signal given by the operator to deactivate intelligent control mode; Logic Force Intelligent Control On (TI) terminal, defined as an input digital signal, connected to the signal generated by the control logic to force activation of intelligent control mode and deactivation of normal automatic control; Logic Force Normal Automatic On (TA) terminal, defined as an input digital signal, connected to the signal generated by the control logic to force deactivation of intelligent control mode and activation of normal automatic control; and Control Mode Indicator (A / I) terminal, defined as an output digital signal, used to indicate whether the control mode is automatic or intelligent control mode; TRUE indicates automatic mode, and FALSE indicates intelligent control mode.

[0072] (2) Improved module output in manual mode: simultaneously tracking feedback values ​​for automatic and intelligent control settings. This is achieved through three analog signal switching logic blocks. When the tracking logic is valid and the TS terminal input is "TRUE", the setting value output SP terminal switches from the non-manual setting value to the value input at the tracking signal TR terminal; the operator setting OA terminal switches to output mode and connects to the value input at the tracking signal TR terminal; the intelligent control setting IC terminal switches to output mode and connects to the value input at the tracking signal TR terminal. At the same time, the control mode indicator A / I terminal output remains unchanged.

[0073] (3) In automatic mode, the improved module outputs the operator setting value, and the intelligent control setting value tracks the automatic setting value. This is achieved through two analog signal switching logic blocks. When the input of the logic for forced exit of intelligent control TA terminal is "TRUE" or the input of the operator exit of intelligent control OTA terminal is "TRUE", and the input of the tracking logic valid TS terminal is "FALSE", the input of the switching logic block connected to the non-manual terminal setting value is switched from the input of the intelligent control setting IC terminal to the input of the operator setting OA terminal; the operator setting OA terminal switches to input mode and receives communication signals from the operator station; the intelligent control setting IC terminal remains in output mode and is connected to the value input of the operator setting OA terminal. At the same time, the output of the control mode indicator A / I terminal is set to TRUE.

[0074] (4) In intelligent control mode, the improved module outputs the intelligent control setting value, and the automatic setting value tracks the intelligent control setting value. This is achieved through two analog signal switching logic blocks. When the input of the logic for forced intelligent control TA terminal is "FALSE" and the input of the logic for forced intelligent control TI terminal is TRUE, or the input of the operator's intelligent control OTA terminal is FALSE and the input of the operator's intelligent control OTI terminal is TRUE, and the input of the tracking logic valid TS terminal is FALSE, the input of the switching logic block connected to the non-manual terminal setting value is switched from the operator setting OA terminal input to the intelligent control setting IC terminal input; the operator setting OA terminal remains in output mode and is connected to the value input of the intelligent control setting IC terminal; the intelligent control setting IC terminal switches to input mode and receives communication signals from the intelligent control station. At the same time, the output of the control mode indicator A / I terminal is set to FALSE.

[0075] (5) The priority order of control mode is manual, which is greater than automatic and intelligent control. This is achieved by arranging the analog signal switching logic blocks. The analog signal switching logic block connected to the valid TS terminal of the tracking logic is placed last. When the input of the valid TS terminal of the tracking logic is TRUE, the control system is in manual mode regardless of the input value of the strong deactivation intelligent control TA terminal or the strong activation intelligent control TI terminal.

[0076] (6) The priority of the control mode is automatically greater than that of the intelligent control mode. This is achieved by using a reset-priority RS flip-flop. When the input of the logic for forced exit of intelligent control TA terminal is TRUE or the input of the operator's exit of intelligent control OTA terminal is TRUE, the RS flip-flop reset terminal is "TRUE", and the input of the switching logic block that connects the output to the non-manual terminal setting value is switched from the input of the intelligent control setting IC terminal to the input of the operator setting OA terminal. When the input of the logic for forced exit of intelligent control TA terminal is FALSE and the input of the logic for forced entry of intelligent control TI terminal is TRUE, or the input of the operator's exit of intelligent control OTA terminal is FALSE and the input of the operator's entry of intelligent control OTI terminal is TRUE, and the input of the tracking logic valid TS terminal is FALSE, the RS flip-flop set terminal is TRUE, and the input of the switching logic block that connects the output to the non-manual terminal setting value is switched from the input of the operator setting OA terminal to the input of the intelligent control setting IC terminal.

[0077] (7) Control mode self-holding. It is still implemented through the RS trigger mentioned above. When the logic forcibly switches to automatic TA or the operator cancels intelligent control OTA, the logic forcibly switches to intelligent control TI or the operator switches to intelligent control OTI, and the control system is switched to the corresponding automatic or intelligent control mode, even if the input becomes FALSE at the next moment, the control mode will still remain automatic or intelligent control mode.

[0078] 2. Configure global variables and OPC-UA communication functions to achieve:

[0079] (8) Set the storage type and signal communication of input / output type variables. When the control logic of the artificial intelligence control system and the traditional analog control system are in the same control unit, in order to meet the read and write call requirements of the input / output type variables connected to the intelligent control setting IC, operator intelligent control OTI, and operator intelligent control OTA terminals of the improved setpoint function block, these variables need to be defined as readable and writable global variables. When the control logic of the artificial intelligence control system and the traditional analog control system are not in the same control unit, it is also necessary to configure an OPC-UA (Unified Open Platform Communication) communication server for the control unit where the improved setpoint function block is located, and add the input / output type quantities connected to the IC, OTI, and OTA terminals to the communication list and configure them as readable and writable. Then, configure an OPC-UA communication client in the control unit where the artificial intelligence control system is located for calling.

[0080] 3. Design the corresponding operation panel in the operation screen and implement it:

[0081] (9) Improve the operation panel of the original analog PID control system. Add features such as... Figure 4The buttons and display signals shown include: Button IM is the intelligent control mode activation button; when pressed by the operator, the control system can enter intelligent control mode. Button AM is the intelligent control mode deactivation button; when pressed by the operator, the control system can exit intelligent control mode. Pressing button IM connects the variable to the operator-activated intelligent control OTI input terminal of the improved setpoint function block; the red or pink background indicates the TRUE status of the A / I output. Pressing button AM connects the variable to the operator-deactivated intelligent control OTA input terminal of the improved setpoint function block; the green or blue background indicates the FALSE status of the A / I output. The default background color for both buttons IM and AM is gray. The number displayed after IS is the intelligent control setpoint signal, and the variable is connected to the intelligent control setting IC input / output terminal of the setpoint function block.

[0082] (10) Logical functions corresponding to operator activation / deactivation of intelligent control mode. The operator activates the intelligent control mode by setting the input of the operator activation intelligent control OTI terminal to TRUE; and activates the automatic control mode by setting the variable connected to the operator deactivation intelligent control OTA terminal to TRUE. The operation effects and priority order of the operator activation intelligent control OTI and operator deactivation intelligent control OTA terminals correspond to the inputs of the logical activation intelligent control TI and logical deactivation intelligent control TA terminals, respectively. OTI and TI are logically ORed, and OTA and TA are logically ORed. The difference is that the OTI and OTA terminals are connected to input / output variables. When the input becomes TRUE at a certain moment, the setpoint module will rewrite it to FALSE at the next moment after processing the signal to adapt to the operation mode of clicking the button on the operation panel.

[0083] 4. Build the lower-level analog PID control configuration logic and write the upper-level artificial intelligence control program, and implement it in the artificial intelligence control system:

[0084] (11) For the upper-level artificial intelligence control system, the following control effects can be achieved by adjusting the setpoint of the lower-level analog PID control system: directly calculate the optimal setpoint or plan the setpoint change curve according to the equipment operating status, and adapt to self-learning, self-adaptation, self-optimization and self-cruise control functions; use the analog PID control system as a sub-loop, build the main loop, feedforward loop or decoupling loop in the artificial intelligence control system, and adapt to the macroscopic intelligent cascade control, feedforward feedback composite control and decoupling control functions; make the setpoint follow the feedback value within a certain range, which can form an equivalent control dead zone, so that the PID control output remains unchanged and realizes the self-holding function under fault and special working conditions; add a fixed bias to the setpoint on the basis of the feedback value, so that the PID control output can act in a determined direction and rate, which is equivalent to manually adjusting the position of the actuator and realizing the override control function under fault and special working conditions.

[0085] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0086] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. An interface logic and operation method for artificial intelligence control to intervene in a traditional analog PID control system by modifying setpoints, characterized in that, This includes improving the setpoint function block of the original analog PID control system to form an improved setpoint function block. The improved setpoint function block adds the following input / output terminals to the original setpoint function block: The intelligent control setting IC is defined as an analog input / output type signal, which is connected to the set value signal given by the artificial intelligence control. The operator-controlled intelligent control OTI terminal is defined as an input / output type switch quantity, which is connected to the signal given by the operator station to activate the intelligent control mode; The operator exits the intelligent control OTA terminal, defined as an input / output type switch quantity, and is connected to the signal given by the operator station to exit the intelligent control mode; The logic is forcibly applied to the intelligent control TI terminal, defined as an input type switch quantity, which is connected to the signal generated by the control logic to forcibly apply the intelligent control mode and exit the normal automatic control mode. The logic forces the switch to the conventional automatic TA terminal, which is defined as an input type switch quantity. It connects to the signal generated by the control logic that forces the switch from intelligent control mode to conventional automatic control. The control mode indicator A / I terminal is defined as an output type switch quantity, used to indicate whether the control mode is automatic or intelligent. When the output is TRUE, it is automatic mode, and when it is FALSE, it is intelligent mode.

2. The method according to claim 1, characterized in that, In manual mode, the improved setpoint function block outputs setpoints, automatic setpoints, and intelligent control setpoints while simultaneously tracking the feedback value of a traditional analog PID control system. This is achieved through three analog signal switching logic blocks. When the tracking logic is valid and the TS terminal input is TRUE, the setpoint output SP terminal switches from the non-manual setpoint to the value input at the tracking signal TR terminal. The operator setting OA terminal switches to output mode and connects to the value input at the tracking signal TR terminal. The intelligent control setting IC terminal switches to output mode and connects to the value input at the tracking signal TR terminal. At the same time, the control mode indicator A / I terminal output remains unchanged.

3. The method according to claim 1, characterized in that, In automatic mode, the improved setpoint function block outputs the operator setpoint and intelligent control setpoint, tracking the automatic setpoint. This is achieved through two analog signal switching logic blocks. When the logic for forced exit of intelligent control (TA) is TRUE or the operator exit of intelligent control (OTA) is TRUE, and the tracking logic is valid (TS) and the input is FALSE, the input of the switching logic block connected to the non-manual setpoint at the SP terminal is switched from the intelligent control setpoint IC input to the operator setpoint OA input. The operator setpoint OA is switched to input mode, receiving communication signals from the operator station. The intelligent control setpoint IC remains in output mode, connected to the value input at the operator setpoint OA. Simultaneously, the control mode indicator A / I output is set to TRUE.

4. The method according to claim 1, characterized in that, In intelligent control mode, the improved setpoint function block outputs the intelligent control setpoint at the SP terminal and tracks the intelligent control setpoint automatically. This is achieved through two analog signal switching logic blocks. When the input of the logic for forced deactivation of intelligent control (TA terminal) is FALSE and the input of the logic for forced activation of intelligent control (TI terminal) is TRUE, or the input of the operator deactivation of intelligent control (OTA terminal) is FALSE and the input of the operator activation of intelligent control (OTI terminal) is TRUE, and the input of the tracking logic (TS terminal) is FALSE, the input of the SP terminal output connected to the switching logic block of the non-manual setpoint is switched from the input of the operator setting (OA terminal) to the input of the intelligent control setting (IC terminal). The operator setting (OA terminal) remains in output mode and is connected to the value input of the intelligent control setpoint (IC terminal). The intelligent control setting (IC terminal) switches to input mode and receives communication signals from the intelligent control station. At the same time, the output of the control mode indicator (A / I terminal) is set to FALSE.

5. The method according to claim 1, characterized in that, The priority order of control modes is manual over automatic and intelligent control: This is achieved by the arrangement of analog signal switching logic blocks connected to the set value output SP terminal. The analog signal switching logic block connected to the tracking logic valid TS terminal is placed last. When the tracking logic valid TS terminal input is TRUE, the control system is in manual mode regardless of the input value of the logic strong off intelligent control TA terminal or the logic strong on intelligent control TI terminal.

6. The method according to claim 1, characterized in that, The control mode priority order is automatically greater than the intelligent control mode: This is achieved through a reset-priority RS flip-flop. When the input of the logic for forced intelligent control TA terminal is TRUE or the input of the operator's intelligent control OTA terminal is TRUE, the RS flip-flop reset terminal is TRUE, and the input of the switching logic block connecting the SP terminal output to the non-manual terminal setting value is switched from the intelligent control setting IC terminal input to the operator setting OA terminal input. When the input of the logic for forced intelligent control TA terminal is FALSE and the input of the logic for forced intelligent control TI terminal is TRUE, or the input of the operator's intelligent control OTA terminal is FALSE and the input of the operator's intelligent control OTI terminal is TRUE, and the input of the tracking logic valid TS terminal is FALSE, the RS flip-flop set terminal is TRUE, and only then is the input of the switching logic block connecting the SP terminal output to the non-manual terminal setting value switched from the operator setting OA terminal input to the intelligent control setting IC terminal input.

7. The method according to claim 1, characterized in that, Self-holding control mode: This is achieved through an RS trigger. When the logic forcibly switches to automatic TA or the operator cancels intelligent control OTA, or the logic forcibly switches to intelligent control TI or the operator switches to intelligent control OTI, and the control system is switched to the corresponding automatic or intelligent control mode, the control mode will remain the automatic or intelligent control mode of the previous moment, even if the input changes to FALSE at the next moment.

8. The method according to claim 1, characterized in that, The improved setting function block's input / output type variables storage type and signal communication method are as follows: When the control logic of the artificial intelligence control system and the traditional analog control system are in the same control unit, the input / output type variables connected to the improved setting function block's intelligent control setting IC, operator intelligent control OTI, and operator intelligent control OTA terminals are defined as readable and writable global variables; when the control logic of the artificial intelligence control system and the traditional analog control system are not in the same control unit, an OPC-UA communication server is configured for the control unit where the improved setting function block is located, and the input / output type variables connected to the IC, OTI, and OTA terminals are added to the communication list and configured as readable and writable modes, and then an OPC-UA communication client is configured in the control unit where the artificial intelligence control system is located for calling.

9. The method according to claim 1, characterized in that, The operation panel of the original analog PID control system has been improved by adding the following buttons and display signals: The IM button is used to activate the intelligent control mode. When the operator presses it, the control system will be activated to intelligent control mode. At the same time, the IM button will trigger a press / release action. The AM button is used to exit the intelligent control mode. When the operator presses it, the control system exits the intelligent control mode, and the AM button triggers a press / release action. The IM button, when clicked, connects the operator to the intelligent control OTI input terminal of the variable connection improvement setting value function block. The red or pink background indicates the TRUE status of the A / I output. The AM button, when clicked, connects the operator to the intelligent control OTA input terminal of the variable connection improvement setting value function block. The green or blue background indicates the FALSE status of the A / I output. The default background color for both the IM and AM buttons is gray. The number displayed after IS is the intelligent control setting value signal, and the variable is connected to the intelligent control setting IC input / output terminal of the setting value function block.

10. The method according to claim 1, characterized in that, The logical functions corresponding to the operator's activation / deactivation of intelligent control modes are as follows: The operator activates the intelligent control mode by setting the input of the operator activation intelligent control OTI terminal to TRUE; the operator deactivates the intelligent control mode by setting the variable connected to the operator deactivation intelligent control OTA terminal to TRUE. The operation effects and priority order of the operator activation intelligent control OTI and operator deactivation intelligent control OTA terminals correspond to the inputs of the logical activation intelligent control TI and logical deactivation intelligent control TA terminals, respectively. OTI and TI are logically ORed, and OTA and TA are logically ORed. The difference is that the OTI and OTA terminals are connected to input / output variables. When the input becomes TRUE at a certain moment, the setpoint module will rewrite it to FALSE at the next moment after processing the signal to adapt to the operation mode of clicking buttons on the operation panel.

11. The method according to any one of claims 1 to 10, characterized in that, The upper-level artificial intelligence control system achieves the following control functions by adjusting the setpoints of the lower-level analog PID control system: Calculate the optimal setpoint or planned setpoint change curve based on the equipment's operating status, and adapt to self-learning, self-adaptation, self-optimization, and self-cruise control functions; The analog PID control system is used as a sub-loop, and the main loop, feedforward loop or decoupling loop is built in the artificial intelligence control system to adapt to the macroscopic intelligent cascade control, feedforward feedback composite control and decoupling control functions. Within a certain range, the set value is made to follow the change of the feedback value, forming an equivalent control dead zone, so that the PID control output remains unchanged, and the self-holding function is realized under fault and special working conditions. The setpoint is based on the feedback value with a fixed bias, so that the PID control output moves in a determined direction and speed, which is equivalent to manually adjusting the position of the actuator and realizing the override control function under fault and special working conditions.

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