A method of converting plc instruction list program into common petri net

Abstract

The invention provides a method for converting a programmable logic controller (PLC) instruction list program into an ordinary Petri network. The method for converting PLC instruction list program into the ordinary Petri network achieves automatic conversion from the PLC instruction list program to the ordinary Petri network. Due to the facts that the ordinary Petri network is concise in excitation conditions, simple in logical thinking mode, visual, and easy to understand, and the obtained ordinary Petri network can completely simulate dynamic behaviors of a PLC control system, the method for the converting PLC instruction list program into the ordinary Petri network provide convenience for analysis and error correction to a PLC program, and can improve reliability of the PLC program.

Description

Technical field [0001] The invention relates to a method for converting a PLC instruction list program into an ordinary Petri net. Background technique [0002] Programmable logic controller (PLC) is a typical controller in industrial control systems, which is widely used in the monitoring and control of steel, petroleum, chemical, electric power and transportation systems. However, the development of PLC programs is facing high complexity problems: with the support of fieldbus technology, the scale and structural complexity of industrial control systems are increasing rapidly, such as subway traffic control systems and nuclear power control systems, etc., and the number of states of the system With the exponential growth of the number of sensors and actuators, the state of the logistics system consisting of only 5 automated navigation vehicles has reached millions, so PLC programming faces inherently high computational complexity. [0003] The high computational complexity brings...

AI Technical Summary

Problems solved by technology

However, the development of PLC programs is faced with high complexity problems: with the support of fieldbus technology, the scale and structure complexity of industrial control systems are increasing rapidly, such as subway traffic control systems and nuclear power control systems, etc., and the number of states of the system As the number of sensors and actuators increases exponentially, the state of a logistics system consisting of only 5 automatic guided vehicles reaches millions, so PLC programming faces inherently high computational complexity

[0003] The high computational complexity brings two major engineering problems: (1) The workload of program design and debugging is cumbersome and huge, and the program development cycle and development cost are difficult to control; (2) Traditional program debugging cannot verify each state (the number of states is exponential level growth), the correctness and reliability of the program cannot be guaranteed, and program errors may cause serious accidents, such as train collisions, European Ariana 5 rocket explosions, and American Threc-5 radioactive medical accidents, etc.

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