The Development Of DSP Controlled Digital Power Source For CO₂ Welding

There are many excellent specific properties for the digital welding power source including higher stability and precision, flexible controlling and good interface compatibility. Now the digital welding power source is the trend of development for welding power supplies. In this paper, a digital welding power source based on DSP(digital signal processor) has been developed, which is designed for CO2 welding.In this paper, the control system's hardware circuits have been designed including DSP's peripheral circuit, adjusting circuit of output signal, signal's feedback circuit, protective and display circuit. According the characteristics of CO2 welding, time-sharing and PID controlling method has been applied. After establishing the system's controlling model, the simulation of control system has been carried out on MATLAB, and the PID's ideal parameters have been worked out. The system's software includes the generating program of PWM signal, A/D conversion program, PID calculation and protection program. The results of experiments indicate that the DSP controlled digital power source for CO2 welding can be controlled flexible and meets all the requirements of CO2 welding.