Study Of Control System Of Digital IGBT Inverter Welding Machine

The study of the digital welding machine system has becoming a hotspot with the development of the welding technologies, control technologies and information technologies. The research presented here concentrated on the control system of the digital IGBT inverter welding machine.IGBT full-bridge inverter structure was adopted in the main circuits, and the principal-subordinate control structure composed of the DSP(TMS320LF2407A) and the MCU(C8051F020) was adopted in the control system of the digital welding machine. The DSP was the core of the system, which would carry out the function of the parameter collection, PI operation and PWM producing; the MCU was used to manage the whole control system, which could control the man-machine interaction system(keyboard and display), the wire feeding motor, some switches and communication between the DSP and the PC. In addition, the serial communication mode between the DSP and the MCU was adopted. The wire feeding circuits and some assistant circuits were designed as well.The modular programs design method was adopted in the software design of the control system. The whole program was divided into several simple and clear subprograms after finished the design of its flow, then the subprograms would be designed, so the complexity of the software design would be play down greatly, the clear, simple and understandable programs would be gained.Some isolative methods which included linear optocouplers and Hall sensors were used in both main circuits and control circuits, and the protective circuits were designed as well, besides many necessary anti-interference methods were adopted in both the hardware design and the software design, which could ensure the stability and reliability of the system.The results of the experiments on the hardware and software of the control circuits showed that the welding machine system has rapid response-speed, high reliability and a strong ability of anti-interference, the software is efficient, which meets the need of the design of the system.At last, some advices on farther research of the welding machine were given after the summarization, which will make a well ground for tomorrow's research of the digital welding machine system.