全数字大功率交流脉冲埋弧焊接电源

In order to improve the welding quality of submerged arc welding, combining the advantages of pulse welding and AC welding, a welding method of AC-Pulse submerged arc welding is proposed, and a high-power AC-Pulse submerged arc welding power source is developed. The power conversion circuit is designed in parallel with two main circuits, which can achieve 1250A AC pulse current output. The secondary circuit adopts coupling inductance structure to accelerate the speed of AC zero-crossing and improve the stability during polarity switching. A digital control system with STM32F405RGT6 chip as the core is built. Through the multi-characteristic digital current sharing strategy, the reliable current sharing of dual main circuits and the stable output of various current waveforms are realized. The discrete incremental PID algorithm is used to improve the dynamic response performance. The process test results show that under the same welding conditions and AC parameters, compared with AC square wave submerged arc welding, AC- Pulse submerged arc welding can obtain larger weld depth and weld width and smaller weld grains.