Built-in PID fuzzy control method based on PLC board card

Abstract

The invention discloses a built-in PID fuzzy control method based on a PLC board card. Fuzzy control rules are determined through sampling data or experience values and are utilized to conduct fuzzification processing on a measurement error e and an error change rate ec to obtain the membership degrees of fuzzy subsets, membership assignment tables of the fuzzy subsets and parameter fuzzy controlmodels are established according to the obtained membership degrees of fuzzy subsets, fuzzy synthesis reasoning is applied to design a fuzzy matrix table for fractional order PID controller parameters, correction parameters are calculated to serve as inputs of the PID controller, values of three control parameters output by the PID controller are automatically adjusted according to the state of acontrolled object, the error e and the error change rate ec serve as inputs, the fuzzy rules are utilized to conduct self-adaptive setting on the output parameters of the PID controller, so that the controlled object is kept in a good dynamic and static state, a user only needs to input the corresponding control parameter values and does not need to compile PLC control programs, the operation difficulty is low, and the stability and reliability are high.

Description

technical field [0001] The invention belongs to the design of a built-in PID fuzzy control algorithm based on a PLC board, in particular to a built-in PID fuzzy control method based on a PLC board. Background technique [0002] PLC is a general-purpose industrial control device based on a microprocessor. It realizes industrial control through its internal integrated instructions, and has been widely used in the field of industrial control. At present, the traditional PID control integrated in the PLC is easy to use and has strong adaptability. At the same time, it has the characteristics of low timing accuracy, poor anti-interference ability, and poor adaptability. The built-in PID control algorithm in the traditional PLC is a traditional PID control algorithm. In the process of use, the user must write the PLC control program by himself to realize the secondary development, the operation is difficult, and the stability and reliability are low. Contents of the invention ...

AI Technical Summary

Problems solved by technology

At present, the traditional PID control integrated in the PLC is easy to use and has strong adaptability. At the same time, it has the characteristics of low timing accuracy, poor anti-interference ability, and poor adaptability. The built-in PID control algorithm in the traditional PLC is a traditional PID control algorithm. In the process of use, the user must write the PLC control program by himself to realize the secondary development, the operation is difficult, and the stability and reliability are low.

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