Fuzzy PID control of induction motor speed regulating system based on PLC

Abstract

Through the analysis of mathematical model of variable frequency speed-regulating system in V/F mode, a fuzzy & PID controller is designed that the structure is simple and the application is easy. The fuzzy control does not require a precise mathematical model of the system or complex computations. It only relies on the human capability to understand the system's behaviour and is based on qualitative control rules. It is applicable on the nonlinear system composed of inverter and induction motor. In this paper, we give the structure of fuzzy controller in AC induction motor speed control system and define fuzzy sets for each input and output variable. Rule tables for fuzzy control are obtained from the analysis of the system behaviour. The experiment results show that the proposed method can be applied effectively and practically in variable frequency speed-regulating system in V/F mode which is nonlinear, fast changeful and difficult to be modelled.