Design of fuzzy control and expert system based MIG arc welding invert power source

Control system based on fuzzy and PI control for MIG welding power source is proposed, aiming at some of deficiencies in the control system based on analogous control technology and single-chip control technology, such as poor flexibility, control precision and reliability. In this control system, the fuzzy control and variable parameter PI control are applied to control the arc voltage and welding current separately, and the parameters of PI controller in different welding conditions are determined by an expert system. A digital signal controller (DSC) and a field programmable gate array (FPGA) realize fuzzy control algorithm and variable parameter PI control algorithm separately. Finally, the hardware circuit and software flow chart of the control system are presented. The experimental results show that the control system based on fuzzy and PI control for MIG welding power source has the advantages of quicker response, better reliability and more stable arc length.