Method capable of rapidly realizing multi-PLC cooperative control

Abstract

The invention relates to the technical field of industrial automation, in particular to a method for quickly realizing multi-PLC cooperative control, which comprises a hardware part mainly consisting of an embedded processor, various communication protocols and an industrial field bus transceiver module, and a software part mainly consisting of a PLC data collection module, a PLC control instruction issuing module and a cooperative control logic module. Through mutual cooperation of a hardware part and a software part, the problems that PLC hardware platforms of manufacturers have differences, the supported PLC programming languages are not completely the same, and communication protocols among different PLCs have standard differences are solved, so that in an industrial automation project involving multi-type PLC cooperative control, the PLC programming languages are not completely the same, and the PLC programming languages are not completely the same are solved. And due to the limitation of universality and compatibility of different PLC devices, the integrated debugging difficulty of the industrial automation project is suddenly increased, and the cost is high.

Description

Technical Field

[0001] The present invention relates to the technical field of industrial automation, and in particular to a method for rapidly realizing multi-PLC coordinated control. Background Art

[0002] PLC (Programmable Logic Controller) is an industrial control device based on a microprocessor. It can realize network communication, process control, logic programming and other functions in industrial automation control. It has the characteristics of simple operation, reliability and stability, and is widely used in the field of industrial automation. In the field of industrial automation, different equipment and systems usually need to be controlled and monitored, so multiple PLCs need to be used at the same time. The simultaneous use of multiple PLCs in an industrial automation process requires reasonable planning in the design stage to ensure smooth communication and collaborative control between the PLCs. In addition, it is necessary to adjust and optimize the program parameters of each PLC according to actual needs and conditions to achieve the best control effect.

[0003] At present, the following methods can usually be used to achieve collaborative control of multiple PLCs:

[0004] 1) Use communication protocols or industrial bus systems: Some PLCs support some communication protocols such as Ethernet, serial communication, CAN, etc., while most current mainstream PLCs support industrial fieldbuses promoted by various PLC manufacturers, such as Modbus-RTU, PROFIBUSDP, DeviceNet, CC-Link, etc. Communication protocols or industrial fieldbuses can be used as a data exchange bridge between two PLCs to achieve collaborative control. The disadvantages are: programming is difficult and requires PLCs to support the same protocol;

[0005] 2) Use the upper computer industrial control software: Some industrial control software provides functional modules or tools for collaborative control. The disadvantage is that the supported PLC models are limited, making it difficult to form a wide range of applications.

[0006] In summary, due to the differences in PLC hardware platforms of various manufacturers, the supported PLC programming languages ​​are not exactly the same, and there are standard differences in the communication protocols between different PLCs. In industrial automation projects involving collaborative control of multiple types of PLCs, due to the limitations of the versatility and compatibility of different PLC devices, the difficulty of integrated debugging of industrial automation projects has increased sharply, and the cost remains high. For this reason, we propose a method that can quickly realize collaborative control of multiple PLCs. Summary of the invention

[0007] The purpose of the present invention is to provide a method for quickly realizing collaborative control of multiple PLCs. The method has the application scenarios that require collaborative control of different types of PLC devices in industrial automation projects, can realize collaborative control between PLCs under different industrial field buses, and can realize unified logic programming of different PLCs through high-level programming languages, thereby reducing the difficulty of implementing collaborative control of multiple PLCs. It solves the problem that due to the differences in PLC hardware platforms of various manufacturers, the supported PLC programming languages ​​are not completely the same, and there are standard differences in communication protocols between different PLCs. In industrial automation projects involving collaborative control of multiple types of PLCs, due to the limitations of the versatility and compatibility of different PLC devices, the difficulty of integrated debugging of industrial automation projects has increased sharply, and the cost remains high.

[0008] To achieve the above object, the present invention provides the following technical solution: a method for quickly realizing multi-PLC collaborative control, comprising: a hardware part mainly composed of an embedded processor, various communication protocols, and an industrial field bus transceiver module, and a software part mainly composed of a PLC data collection module, a PLC control instruction issuing module, and a collaborative control logic module. The collaborative control scheme of the hardware part is as follows:

[0009] 1) Various communication protocols and industrial field bus transceiver modules can realize data transmission and reception of various interfaces, such as serial port, Ethernet port, Modbus-RTU bus interface, PROFIBUSDP bus interface and other communication protocols and industrial field bus, convert the received data into the internal bus protocol that can be processed by the embedded processor, and support the conversion of internal data into the corresponding protocol and send it to the corresponding interface;

[0010] 2) The embedded processor obtains data from each transceiver module, processes it, and then outputs the processing results to each transceiver module;

[0011] The scheme of the collaborative control of the software part is as follows:

[0012] 1) PLC data collection module collects and organizes the data reported by PLC, obtains and records the status information of each PLC input IO;

[0013] 2) PLC control instruction issuing module sends the status information of each PLC output IO to each interface for each PLC to read and execute the corresponding output IO operation;

[0014] 3) The collaborative control logic module comprehensively judges the status information of each PLC and obtains the target status of each PLC output IO through system logic processing. The control logic can be executed by timing loop execution, or in real time for a specific PLC input IO, or by a combination of the two.

[0015] The hardware part and the software part cooperate with each other to realize the method of multi-PLC collaborative control, and the specific implementation steps are as follows:

[0016] Preliminary preparation: Change the built-in programs of the PLC devices involved in the project to the following states: In each PLC scan cycle, the state value of the PLC input IO is reported to the PLC data collection module through the PLC communication interface; in each PLC scan cycle, the control instructions are read through the PLC communication interface, and the corresponding PLC output IO is changed to the target state;

[0017] Step ①: Initialize the main program and complete the configuration of each transceiver module;

[0018] Step ②: Set the trigger condition of interrupt A to the transceiver module receiving the input IO status information reported by the PLC. The processing flow of interrupt A is: read the PLC input IO status and synchronously update the locally stored PLC status information. For the reported input IO status, determine whether there is an operation that needs to be processed immediately. If so, immediately calculate the target state value of each PLC output IO based on the locally stored PLC status information and send it to each PLC through the transceiver module. If not, directly end this interrupt operation;

[0019] Step 3: Set the trigger condition of interrupt B to trigger according to the preset time interval and timed loop. The processing flow of interrupt B is: according to the system logic, based on the locally stored status information of each PLC, calculate the target state value of each PLC output IO and send it to each PLC through the transceiver module;

[0020] Step ④: Enable interrupt A and interrupt B, set the priority of interrupt A higher than that of interrupt B, and the program enters the state of waiting for interrupt trigger and executing interrupt operation.

[0021] Preferably, various types of transceiver modules in the hardware part can be increased or decreased according to the types and quantities of the actually connected PLCs.

[0022] Preferably, the hardware part can realize signal interconnection with mainstream PLC models of various brands through various communication protocols and industrial field bus transceiver modules.

[0023] Preferably, the logical functions of the collaborative control can be implemented through high-level language programming, such as C++, Python and other high-level languages.

[0024] Preferably, the collaborative control uses security measures such as access control systems and surveillance cameras to limit physical access by unauthorized personnel to prevent the equipment from being illegally tampered with or destroyed. At the same time, network isolation technologies such as VLAN division and network segment isolation are used to isolate the PLC network from other networks to reduce the potential attack surface, and an intrusion detection system (IDS) or intrusion prevention system (IPS) is installed to monitor and defend against network attacks in real time.

[0025] Preferably, the collaborative control uses encryption technology to encrypt the communication between the PLC and other devices to ensure confidentiality and integrity during data transmission, and regularly updates the operating system and application programs of the PLC devices to fix known vulnerabilities and security issues.

[0026] Preferably, the collaborative control regularly backs up the PLC's programs and data to prevent data loss or damage. The backup data should be stored in a secure location and encrypted for protection. A disaster recovery plan should be developed to clearly define how to quickly restore the PLC's functions and data in the event of a security incident or system failure. The logging function of the PLC device and network should be enabled to record all key operations and activities in order to track and analyze potential security incidents.

[0027] Preferably, the collaborative control configures a backup PLC to ensure that when a main PLC fails, the backup PLC can seamlessly take over the execution of the application.

[0028] Preferably, the standby PLC reads inputs through redundant links and synchronizes with the activated PLC to achieve master-slave switching, configure redundant network devices or adopt network redundancy protocols such as STP, RSTP, etc. to ensure network availability and stability.

[0029] Preferably, the collaborative control adopts a dual power supply design and configures multiple I / O modules to achieve redundant design of input and output signals.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. Support collaborative control between PLCs of different manufacturers and models.

[0032] 2. The collaborative control logic is implemented on the embedded processor, and the collaborative control logic of multiple PLCs can be programmed simultaneously using high-level languages ​​such as C++ and Python, which changes the traditional mode of multi-PLC collaborative control that requires PLC programming one by one, and reduces the difficulty of implementation.

[0033] 3. During on-site debugging, all PLC logic modifications can be achieved by simply changing the program on the embedded processor, which can save the time required for multi-PLC integrated debugging. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the hardware components of the present invention;

[0035] Figure 2 It is a flow chart of the present invention;

[0036] Figure 3 The following is a block diagram of the system composition of a typical implementation mode of the present invention. DETAILED DESCRIPTION

[0037] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] See also Figure 1-Figure 2 As shown, the present invention provides a technical solution: a method for quickly realizing multi-PLC collaborative control, including a hardware part mainly composed of an embedded processor, various communication protocols, and an industrial field bus transceiver module, and a software part mainly composed of a PLC data collection module, a PLC control instruction issuing module, and a collaborative control logic module. The collaborative control scheme of the hardware part is as follows:

[0039] 1) Various communication protocols and industrial field bus transceiver modules can realize data transmission and reception of various interfaces, such as serial port, Ethernet port, Modbus-RTU bus interface, PROFIBUSDP bus interface and other communication protocols and industrial field bus, convert the received data into the internal bus protocol that can be processed by the embedded processor, and support the conversion of internal data into the corresponding protocol and send it to the corresponding interface;

[0040] 2) The embedded processor obtains data from each transceiver module, processes it, and then outputs the processing results to each transceiver module;

[0041] The scheme for collaborative control of the software part is as follows:

[0042] 1) PLC data collection module collects and organizes the data reported by PLC, obtains and records the status information of each PLC input IO;

[0043] 2) PLC control instruction issuing module sends the status information of each PLC output IO to each interface for each PLC to read and execute the corresponding output IO operation;

[0044] 3) The collaborative control logic module comprehensively judges the status information of each PLC and obtains the target status of each PLC output IO through system logic processing. The control logic can be executed by timing loop execution, or in real time for a specific PLC input IO, or by a combination of the two.

[0045] The hardware part and the software part cooperate with each other to realize the method of multi-PLC collaborative control. The specific implementation steps are as follows:

[0046] Preliminary preparation: Change the built-in programs of the PLC devices involved in the project to the following states: In each PLC scan cycle, the state value of the PLC input IO is reported to the PLC data collection module through the PLC communication interface; in each PLC scan cycle, the control instructions are read through the PLC communication interface, and the corresponding PLC output IO is changed to the target state;

[0047] Step ①: Initialize the main program and complete the configuration of each transceiver module;

[0048] Step ②: Set the trigger condition of interrupt A to the transceiver module receiving the input IO status information reported by the PLC. The processing flow of interrupt A is: read the PLC input IO status and synchronously update the locally stored PLC status information. For the reported input IO status, determine whether there is an operation that needs to be processed immediately. If so, immediately calculate the target state value of each PLC output IO based on the locally stored PLC status information and send it to each PLC through the transceiver module. If not, directly end this interrupt operation;

[0049] Step 3: Set the trigger condition of interrupt B to trigger according to the preset time interval and timed loop. The processing flow of interrupt B is: according to the system logic, based on the locally stored status information of each PLC, calculate the target state value of each PLC output IO and send it to each PLC through the transceiver module;

[0050] Step ④: Enable interrupt A and interrupt B, set the priority of interrupt A higher than that of interrupt B, and the program enters the state of waiting for interrupt trigger and executing interrupt operation.

[0051] Among them, various types of transceiver modules in the hardware part can be increased or decreased according to the type and quantity of the actual connected PLCs.

[0052] Among them, the hardware part can realize signal interconnection with mainstream PLC models of various brands through various communication protocols and industrial field bus transceiver modules.

[0053] Among them, the logical functions of collaborative control can be implemented through high-level language programming, such as C++, Python and other high-level languages.

[0054] Among them, collaborative control uses security measures such as access control systems and surveillance cameras to limit physical access by unauthorized personnel and prevent equipment from being illegally tampered with or destroyed. At the same time, network isolation technologies such as VLAN division and network segment isolation are used to isolate the PLC network from other networks to reduce the potential attack surface, and install intrusion detection systems (IDS) or intrusion prevention systems (IPS) to monitor and defend against network attacks in real time.

[0055] Through the above technical solutions, the physical security and network security of the collaborative control method can be improved, avoiding security risks brought by external factors and the network.

[0056] Among them, collaborative control uses encryption technology to encrypt communications between PLC and other devices to ensure confidentiality and integrity during data transmission, and regularly updates the operating system and applications of PLC devices to fix known vulnerabilities and security issues.

[0057] Through the above technical solutions, the collaborative control method can ensure the confidentiality and integrity of data transmission and avoid loopholes and security.

[0058] Among them, collaborative control should regularly back up PLC programs and data to prevent data loss or damage. Backup data should be stored in a secure location and encrypted for protection. A disaster recovery plan should be developed to clearly define how to quickly restore PLC functions and data in the event of a security incident or system failure. The logging function of PLC devices and networks should be enabled to record all key operations and activities in order to track and analyze potential security incidents.

[0059] Through the above technical solutions, the collaborative control method adds backup and recovery as well as monitoring and auditing, ensuring the normal use of the method.

[0060] Among them, collaborative control configures a backup PLC to ensure that when the main PLC fails, the backup PLC can seamlessly take over the execution of the application.

[0061] Among them, the standby PLC reads the input through the redundant link and synchronizes with the activated PLC to achieve master-slave switching, configure redundant network devices or adopt network redundancy protocols such as STP, RSTP, etc. to ensure the availability and stability of the network.

[0062] Among them, the collaborative control adopts a dual power supply design and configures multiple I / O modules to achieve redundant design of input and output signals.

[0063] Best Mode for Carrying Out the Invention

[0064] A typical implementation method of the method for rapidly implementing multi-PLC coordinated control described in the present invention is mainly composed of the following, and reference is made to the attached Figure 3 As shown:

[0065] (1) Implementation of various transceiver modules

[0066] Serial port, CAN, Modbus-RTU and other protocol transceiver circuits are used to realize the transmission and reception of various protocol data, and convert the data into the form of network messages. At the same time, it supports the conversion of network message data into serial port, CAN and other protocol data for transmission.

[0067] (2) Implementation of collaborative control logic module

[0068] Using Rockchip RK3588S embedded processor and running Ubuntu 22.04 operating system, the PLC input IO status data reported by each transceiver template is obtained from the Ethernet bus interface, and then the target status value of each PLC output IO is obtained through system logic processing, and the result is sent to each transceiver module.

[0069] (3) Implementation of internal bus

[0070] The standard Ethernet bus exchange module is used to realize the exchange of internal bus data, which mainly includes: various transceiver modules convert the data of serial port, CAN and various industrial field bus protocols into Ethernet protocol messages; and the processing result data of Ethernet protocol output by the collaborative control logic module.

[0071] (4) Supporting circuit

[0072] Supporting functional circuits required in the system, such as storage modules, power modules, etc.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention, rather than to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the essence and scope of the technical solution of the present invention.

Claims

1. A method for quickly realizing multi-PLC collaborative control, characterized in that: include: The hardware part mainly consists of an embedded processor, various communication protocols, and an industrial field bus transceiver module, and the software part mainly consists of a PLC data collection module, a PLC control instruction issuing module, and a collaborative control logic module. The collaborative control scheme of the hardware part is as follows: 1) Various communication protocols and industrial field bus transceiver modules can realize various interfaces, convert the received data into internal bus protocols that can be processed by the embedded processor, and support converting the internal data into the corresponding protocol and sending it to the corresponding interface; 2) The embedded processor obtains data from each transceiver module, processes it, and then outputs the processing results to each transceiver module; The scheme of the collaborative control of the software part is as follows: 1) PLC data collection module collects and organizes the data reported by PLC, obtains and records the status information of each PLC input IO; 2) PLC control instruction issuing module sends the status information of each PLC output IO to each interface for each PLC to read and execute the corresponding output IO operation; 3) The collaborative control logic module comprehensively judges the status information of each PLC and obtains the target status of each PLC output IO through system logic processing. The control logic can be executed by timing loop execution, or in real time for a specific PLC input IO, or by a combination of the two. The hardware part and the software part cooperate with each other to realize the method of multi-PLC collaborative control, and the specific implementation steps are as follows: Preliminary preparation: Change the built-in programs of the PLC devices involved in the project to the following states: In each PLC scan cycle, the state value of the PLC input IO is reported to the PLC data collection module through the PLC communication interface; in each PLC scan cycle, the control instructions are read through the PLC communication interface, and the corresponding PLC output IO is changed to the target state; Step ①: Initialize the main program and complete the configuration of each transceiver module; Step ②: Set the trigger condition of interrupt A to the transceiver module receiving the input IO status information reported by the PLC. The processing flow of interrupt A is: read the PLC input IO status and synchronously update the locally stored PLC status information. For the reported input IO status, determine whether there is an operation that needs to be processed immediately. If so, immediately calculate the target state value of each PLC output IO based on the locally stored PLC status information and send it to each PLC through the transceiver module. If not, directly end this interrupt operation; Step 3: Set the trigger condition of interrupt B to trigger according to the preset time interval and timed loop. The processing flow of interrupt B is: according to the system logic, based on the locally stored status information of each PLC, calculate the target state value of each PLC output IO and send it to each PLC through the transceiver module; Step ④: Enable interrupt A and interrupt B, set the priority of interrupt A higher than that of interrupt B, and the program enters the state of waiting for interrupt trigger and executing interrupt operation.

2. A method for rapidly implementing multi-PLC collaborative control according to claim 1, characterized in that: The various transceiver modules of the hardware part can be increased or decreased according to the type and quantity of the actually connected PLCs.

3. The method for rapidly realizing multi-PLC coordinated control according to claim 1 is characterized in that: The hardware part can realize signal interconnection with mainstream PLC models of various brands through various communication protocols and industrial field bus transceiver modules.

4. The method for rapidly implementing multi-PLC coordinated control according to claim 1 is characterized in that: The logical functions of the cooperative control can be implemented through high-level language programming.

5. The method for rapidly realizing multi-PLC coordinated control according to claim 1 is characterized in that: The collaborative control adopts security measures such as access control systems and surveillance cameras to limit physical access by unauthorized personnel and prevent the equipment from being illegally tampered with or destroyed. At the same time, network isolation technologies such as VLAN division and network segment isolation are adopted to isolate the PLC network from other networks to reduce the potential attack surface, and intrusion detection systems or intrusion prevention systems are installed to monitor and defend against network attacks in real time.

6. The method for rapidly implementing multi-PLC coordinated control according to claim 5 is characterized in that: The collaborative control uses encryption technology to encrypt the communication between PLC and other devices to ensure confidentiality and integrity during data transmission, and regularly updates the operating system and application programs of PLC devices to fix known vulnerabilities and security issues.

7. A method for rapidly implementing multi-PLC coordinated control according to claim 6, characterized in that: The collaborative control shall regularly back up the PLC programs and data to prevent data loss or damage. The backup data shall be stored in a secure location and encrypted for protection. A disaster recovery plan shall be formulated to clearly define how to quickly restore the PLC functions and data in the event of a security incident or system failure. The logging function of the PLC devices and networks shall be enabled to record all key operations and activities in order to track and analyze potential security incidents.

8. The method for rapidly implementing multi-PLC coordinated control according to claim 1, characterized in that: The collaborative control configures a standby PLC to ensure that when a main PLC fails, the standby PLC can seamlessly take over the execution of the application program.

9. A method for rapidly implementing multi-PLC coordinated control according to claim 8, characterized in that: The standby PLC reads inputs through redundant links and synchronizes with the active PLC to implement master-slave switching, configure redundant network devices or adopt network redundancy protocols.

10. A method for rapidly implementing multi-PLC coordinated control according to claim 9, characterized in that: The collaborative control adopts a dual power supply design and configures multiple I / O modules to achieve redundant design of input and output signals.

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