A ring network control method and control system applied to a control system

Abstract

This invention discloses a ring network control method applied to a control system. The control system forms a ring network by cascading a local main control module with multiple remote communication modules. The ring network control method utilizes the built-in processor in the main control module to determine the ring network status and issue network port control commands. The remote communication modules then control I / O devices and the transmission of ring network messages according to the issued commands. This invention provides unified management of the switching chips by the processor. Message processing is handled by the powerful processor, which determines the message transmission direction and status. The switching chips receive control commands and ring network detection messages from the processor and forward data according to the processor's execution commands. This unified management by the processor effectively improves message transmission efficiency and system stability.

Description

Technical Field

[0001] This invention relates to the field of automation control, and particularly to a ring network control method applied to control systems. This control method allows a local master control module and a remote communication module to replace conventional management ring network equipment and the ring network itself. Background Technology

[0002] With the continuous development of industrial automation, higher requirements have been placed on the reliability and stability of field control equipment. Currently, control systems use methods such as controller redundancy, module redundancy, communication link redundancy, power supply redundancy, and network equipment redundancy to improve system reliability.

[0003] Network device redundancy involves ensuring the stable operation of the control system by taking over the redundant network link when a segment or node in a network connection fails. Common redundancy methods include the conventional star network model and the ring network model. While the conventional star network model can handle network failures, its complex topology makes troubleshooting and maintenance difficult. Currently, most common ring network models utilize industrial switches that support ring network self-healing. The use of numerous switches increases system costs and complicates troubleshooting. Summary of the Invention

[0004] The purpose of this invention is to reduce the complexity of ring network topologies and facilitate subsequent network maintenance. By placing the judgment and processing of ring network status on a local main control module and a remote communication module, this invention makes the main control module more powerful, reduces reliance on other network expansion devices, improves the stability of the control system, and makes the control system using this invention more applicable to various industrial applications.

[0005] The technical solution adopted in this invention is as follows:

[0006] A ring network control method for a control system is disclosed. The control system forms a ring network by cascading a local main control module with multiple remote communication modules. The ring network control method of the present invention uses the built-in processor of the controller of the main control module to realize the ring network status judgment and the issuance of network port control commands, and uses the remote communication modules to control I / O devices and transmit ring network messages according to the issued commands.

[0007] The main control module's processor determines and processes the ring network status as follows: The processor periodically sends a detection message with its own identifier via the Ethernet interface, and performs ring network detection message judgment on messages received via the other Ethernet interface, comparing them with its own identifier to determine if the message was sent by this processor. If so, the control system is determined to be in a ring network state. The processor sends a control command to the switching chip, which then controls the two Ethernet interfaces, allowing one interface to send and receive data normally, while the other interface is blocked and can only receive ring network detection messages. If no detection message is received within a certain period, a ring network fault is determined. The processor sends a control command to the switching chip, which then opens both Ethernet interfaces, allowing data to be transmitted bidirectionally along the directions of the two Ethernet interfaces.

[0008] This invention uses a local main control module as the management device to determine the ring network status and issue network port control commands. The controller's built-in processor parses the control command messages and ring network detection messages. The parsed messages are then sent and received uniformly by the switching chip, thereby constructing a ring network topology.

[0009] Unlike traditional ring self-healing network topologies that rely heavily on external network expansion modules, where the controller's processor cannot centrally manage these modules and cannot respond promptly to system malfunctions, this invention addresses this issue by providing unified management of the switching chips by the processor. Packet processing is handled by a powerful processor that determines packet transmission direction and status. The switching chips receive control commands and ring network detection messages from the processor and forward data according to the processor's instructions. This unified management by the processor significantly improves packet transmission efficiency and system stability.

[0010] Furthermore, the detection messages periodically sent by the processor include its own MAC address. The purpose of including the MAC address is to prevent misjudgments of the ring network status caused by multiple controllers in a control system, which could lead to network paralysis.

[0011] Furthermore, the aforementioned ring network control method utilizes the built-in processor of the remote communication module's controller to respond to ring network detection messages. The processor of the main control module analyzes the messages to locate the network fault location. The network fault location logic includes: when the processor of the remote communication module receives the ring network detection message from the local main control module, it generates a response message with its own identifier and sends it to the processor of the main control module. The processor of the main control module locates the location of the network communication fault based on the response message.

[0012] The present invention also provides a control system comprising a ring network topology constructed from a local master control module and multiple remote communication modules; the controllers of both the master control module and the remote communication modules include:

[0013] The processor implements the controller's control logic, analyzes the ring network logic, and issues corresponding action instructions.

[0014] The switching chip controls the Ethernet interface according to commands issued by the processor;

[0015] Two Ethernet interfaces serve as the transmission interfaces for the controller's control commands and ring network detection messages.

[0016] The controller's control command messages and ring network detection messages are processed by the processor, and the switching chip manages the Ethernet ports in a unified manner. The messages processed by the processor are sent and received by the switching chip in a unified manner to build a ring network topology. The main purpose is to improve message transmission efficiency and system stability.

[0017] Furthermore, each processor connects to its corresponding switching chip via the MII interface and manages the communication interface through the SMI communication protocol.

[0018] Furthermore, each switching chip is connected to the PHY via the RGMII interface, thereby controlling the Ethernet interface. The switching chip forwards the collected detection messages to the processor through the communication interface. The processor analyzes and processes the messages, and determines the switching chip's action based on the results of the ring network's judgment logic analysis. When a network communication failure occurs at a certain point, the processor analyzes the messages and locates the network fault.

[0019] Furthermore, the remote communication module controls the I / O devices via the EBUS bus.

[0020] The present invention has the following advantages over the prior art:

[0021] 1) The processor directly participates in the sending and receiving of ring network detection messages, improving system stability.

[0022] 2) The remote communication module can respond to the ring network detection messages. The processor can accurately locate the network fault based on the response messages, which facilitates network maintenance. Attached Figure Description

[0023] Figure 1 This is the topology of the control method for the local main control module and the remote communication module of the present invention.

[0024] Figure 2 This is the network topology for normal communication in this invention.

[0025] Figure 3 This is a schematic diagram illustrating the change in network path when a communication failure occurs at a certain point in the present invention. Detailed Implementation

[0026] The invention will now be further described with reference to the accompanying drawings.

[0027] This invention discloses a ring network control method for control systems, applied to a ring network topology composed of a local master control module and a remote communication module. The main objective of this method is to enhance the processor's message processing capabilities without affecting the original functions of the local master control module and the remote communication module. Without relying on other network expansion modules, the master control module handles the sending and receiving of ring network messages and status judgments, while the local master control module handles message sending and receiving, message parsing, and corresponding action processing, achieving a self-healing ring network topology. Furthermore, based on messages fed back from the remote communication module, the method accurately locates network faults, reducing system costs and increasing system stability. This method constructs a self-healing ring network topology by cascading the A and B network ports of the local master control module and the remote communication module in multiple levels. When a network fault occurs, the local master control module can determine the cause and change the network communication path to continue communication. This ensures the control system maintains normal operation and network communication redundancy, while also making the network topology simpler and clearer.

[0028] like Figure 1 This invention includes a local main control module and a remote communication module. These two modules transmit and receive data via Ethernet ports. Each module has two Ethernet interfaces, and by connecting the corresponding interfaces, a simple ring network topology is formed. The processor 11 of the local main control module is responsible for processing the entire control logic, monitoring communication with the equipment, and controlling the field equipment. It also transmits control data and ring network detection data to the switching chip via the MII interface. The switching chip 12 transmits the data to the Ethernet interface 14 via the RGMII interface, and then actively transmits it to the remote communication module. The switching chip of the remote communication module receives the control data sent by the local main control module via the Ethernet interface 14 through the RGMII interface and uploads it to the MII interface. The processor of the remote communication module controls the I / O devices to operate. The processor generates a ring network detection response message and transmits this message, along with the control data and ring network detection data received from Ethernet interface 24, to the switching chip. The switching chip then forwards all this data to the processor of the local master control module through Ethernet interface 23 according to the forwarding rules. Since the ring network detection message is sent by the processor of the local master control module and is received, it is determined that the network is in a ring state. If the ring network detection message sent by this module in the previous cycle is not received, the processor determines that there is a fault in a certain part of the ring network and locates the fault location based on the response message sent by the remote communication module.

[0029] When the processor of the local master control module determines that the network status is a ring network, the processor of the local master control module sends a port blocking control command to the switching chip. At this time, the switching chip controls the Ethernet interface 14 to maintain its original function and continue to execute the sending and receiving of control data and ring network detection messages, and controls the Ethernet interface 13 to block so that it can only receive ring network detection messages, thus avoiding the network storm problem caused by data sent from itself flowing back to itself.

[0030] When the processor of the local main control module determines that a network communication failure has occurred at a certain point in the ring network, its processor sends a control command to the switching chip to change its communication path. The switching chip then opens both Ethernet interfaces 13 and 14, enabling them to send and receive data normally. If the network cable connecting Ethernet interface 13 to Ethernet interface 23 is faulty, the local main control module can achieve network communication through Ethernet interfaces 14 and 24. Similarly, it can be seen that when a network failure occurs, it will not affect the normal operation of the control system.

[0031] like Figure 2 The diagram shows a ring network consisting of a local master control module and a remote communication module during normal communication. In this network topology, the local master control module initiates the transmission of control data messages and ring network detection messages via the Ethernet port. Each time data passes through a remote communication module, the module parses its control command message and controls its I / O modules. If a ring network detection message is received, a response message is generated and transmitted back to the local master control module. This process continues until the data flows to another port of the local master control module. The master control module then blocks that port, losing all control data messages and retaining only the ring network detection message. This completes a network communication link.

[0032] like Figure 3 The diagram illustrates a network failure in a ring network consisting of a local control module and a remote communication module. When the ring network topology malfunctions, the local control module will no longer receive its own ring network detection messages. At this point, the processor of the local control module will send a control command to the switching chip to change the network communication path. The local control module will then begin transmitting along the communication directions of the two ports, thus establishing two complete network communication links for the control system. This does not affect the stable operation of the control system. Furthermore, when the ring network topology malfunctions, the response messages received by the processor of the local control module from the remote communication module will also become incomplete. By parsing these response messages, the processor can determine the specific location of the ring network topology problem, facilitating maintenance after the problem occurs.

[0033] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements without departing from the principle of the present invention, and these improvements should also be considered within the scope of protection of the present invention.

Claims

1. A ring network control method applied to a control system, characterized in that, The control system forms a ring network by cascading a local main control module with multiple remote communication modules; the ring network control method uses the built-in processor of the main control module to determine the ring network status and issue network port control commands, and uses the remote communication modules to control I / O devices and transmit ring network messages according to the issued commands. The main control module's processor determines and processes the ring network status as follows: The processor periodically sends a detection message with its own identifier via the Ethernet interface, and performs ring network detection message judgment on messages received via the other Ethernet interface, comparing them with its own identifier to determine if the message was sent by this processor. If so, the control system is determined to be in a ring network state. The processor sends a control command to the switching chip, which then controls the two Ethernet interfaces, allowing one interface to send and receive data normally, while the other interface is blocked and can only receive ring network detection messages. If no detection message is received within a certain period, a ring network fault is determined. The processor sends a control command to the switching chip, which then opens both Ethernet interfaces, allowing data to be transmitted bidirectionally along the directions of the two Ethernet interfaces.

2. The ring network control method applied to a control system according to claim 1, characterized in that, The ring network control method uses the built-in processor of the remote communication module's controller to respond to ring network detection messages, and the processor of the main control module analyzes the messages to locate the network fault location. The network fault location logic includes: when the processor of the remote communication module receives the ring network detection message from the local main control module, it generates a response message with its own identifier and sends it to the processor of the main control module. The processor of the main control module locates the location of the network communication fault based on the response message.

3. A control system employing the ring network control method described in claim 1 or 2, characterized in that, The control system consists of a ring network topology constructed from a local master control module and multiple remote communication modules; the controllers of both the master control module and the remote communication modules include: The processor implements the controller's control logic, analyzes the ring network logic, and issues corresponding action commands. The switching chip controls the Ethernet interface according to commands issued by the processor; Two Ethernet interfaces serve as the transmission interfaces for the controller's control commands and ring network detection messages.

4. The control system according to claim 3, characterized in that, The processor connects to the corresponding switching chip via the MII interface.

5. The control system according to claim 4, characterized in that, The switching chip is connected to the PHY via the RGMII interface, thereby controlling the Ethernet interface.

6. The control system according to claim 5, characterized in that, The remote communication module controls the I / O devices via the EBUS bus.

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