Simulation Study On Soft - Switching IGBT Inverter Arc Welding Power Supply

This research is based on the inverter and soft switch core power technology, independent establishment phase shifted full bridge zero voltage and zero current PWM control inverter main circuit(FB-ZVZCS-PWM), comprehensive study on the control system of inverter power source based on DSP, from two aspects of the system hardware and software.This research relies on TI Company’s digital signal processing chip —TMS320F2812, and coordinates Tech_V-2812 embedded control board as the minimum DSP applications. In the hardware of control system, this research designed the current and voltage sampling feedback circuit, IGBT driving circuit and the welding parameters preset and display circuit. In the software of control system, this research based on the discrete theory research developed the multi-function control system software program, which including the main program, interrupt program and fuzzy control subroutine.Based on the MATLAB software simulation tool of Simulink, this research multi parametric built the phased-shift PWM control model, the power load model and the main circuit whole model, and relies on the simulation data proved that the main circuit well achieved zero voltage turn-on of the advanced bridge and zero current turn-off of the retarding bridge. At the same time, this research established the current and voltage sample hold model, the soft-start model and constant voltage, constant current, outer-drawing current power external characteristics simulation models. In the simulation of constant voltage、 constant current power source external characteristics, this research determined the quantization factor and scaling factor of the fuzzy controller, and simulate the parameter waveform of arc welding voltage and current in various external characteristics under different load conditions, and it proved that the models of power source control system can achieve the desired output external welding characteristics.The main circuit, control circuit and related model of diversification by the development of multi parameter, level of development have higher accuracy, which provides a theoretical basis for the actual operation of welding equipment.