Abstract: To overcome three different phase status for the waveform output in twin-wire high speed welding process, including synchronization, alternation and random, a DSP based digital synchronic control system for twin-wire high speed welding is presented. By adopting the PWM generation modules integrated in DSP, the digital control of the PWM signal is realized in software mode, so the high frequency inverter and low frequency pulsed waveform modulation of master and slave power supplies are realized. The three different phase status for the waveform output is realized in single chip DSP. The design of hardware and software to the digital synchronic control system is also discussed. The results of welding experiment demonstrate that the developed digital synchronic control system meets the design requirements, and the merits of the twin-wire high speed welding are stable welding process, high welding speed, less splash and perfect weld seam formation.

Key words: Digital control, Digital signal processor, Synchronic control, Twin-wire high speed welding