Research And Design Of Inverter Welding Power With Fuzzy Controller

Weld is an important method in process, welding power is the key factor whichdetermines the quality of weld. Inverter welding power has developed rapidly becauseof its advantages such as high efficiency, energy saving, small bulk, light weight andmultifunction etc. Fuzzy control has been applied in many fields, with thedevelopment of microcomputer technology, it becomes realiable to use fuzzy controlin welding power. The purpose of this subject is to develop high performance,economical and practical welding power, the newest soft-switch invert technology andadvanced fuzzy control method combined to design welding power.The main content of this subject is to design a full-bridge shift-phase inverterwelding power with fuzzy controller, in the base of analyzing the running principle offull-bridge zero-voltage-switch inverter. The design of main circuit is introduced indetail. This design includes the selection and protection of elements, the designmethod and calculation of high frequency transformer. In this subject, the low costand integrated microcomputer are applied. The hardware circuit of this welding poweris designed based on Philips's 89C58 single chip computer. In order to realize the softswitch of inverter, the shift-phase PWM control method is adopted. The weldingcurrent closed loop feedback control and fuzzy control systems are applied to gain theconstant welding current external characteristics. Many anti-jamming measures areused to protect the reliability of control system. According to the functions of thewelding power, the software is developed which includes main program, interruptservice routines and some function subprograms. The design of two input and singleoutput fuzzy controller is introduced in detail. The whole system is debugged andtested after completing software and hardware design of the welding power. Theresults make clear that this welding power can export prospective constant currentcharacteristic, and the inverter has excellent dynamic capabilities with fuzzycontroller.