CO2气体保护焊的新型全数字化波形控制技术

对于逆变弧焊电源,采用基于 DSP 的全数字控制策略.针对短路过渡 CO2 气体保护焊特点,提出了准恒压全数字化新型波形控制策略,不再根据输出电压区分短路和燃弧过程,使得短路和燃弧过程过渡自然,适应于所有的焊接工艺,提高了系统的适应性.同时在短路初期采用瞬态电流抑制技术减少了飞溅,建立了包含实时燃弧能量补充机制的全数字化电压电流瞬时反馈的全数字三闭环控制模型.结果表明,所提出的全数字化软开关控制策略灵活、可靠;所采用的数字波形控制技术适应性好、灵活、焊接过程稳定、焊缝成形优良.

Abstract：

According to the characteristics of short circuit transfer of CO2 gas metal arc welding, a novel full digital waveform control scheme called quasi-constant voltage control is presented for inverter type arc welding power based on DSP. Short circuit and arc ignition process are not judged according to the output voltage and transfer process between them is smooth. The strategy is also applied to all welding conditions. Initial current at the instant of short-circuit is suppressed to reduce spatter generation. A triple closed loop control model including real time energy compensation for the arc state based on instantaneous voltage and current feedback control is estabhshed. Flexibility and reliability of the proposed fully digitalized softswitching control strategy is validated by experimental results of 400 A welding machine. The experimental results show that proposed digital waveform control scheme is applicable for different wire feeding speed conditions, and the welding process is stable and the welding bead appearance is good.

A novel digital waveform control scheme for CO_2 gas metal arc welding

According to the characteristics of short circuit transfer of CO2 gas metal arc welding, a novel full digital waveform control scheme called quasi-constant voltage control is presented for inverter type arc welding power based on DSP. Short circuit and arc ignition process are not judged according to the output voltage and transfer process between them is smooth. The strategy is also applied to all welding conditions. Initial current at the instant of short-circuit is suppressed to reduce spatter generation. A triple closed loop control model including real time energy compensation for the arc state based on instantaneous voltage and current feedback control is estabhshed. Flexibility and reliability of the proposed fully digitalized softswitching control strategy is validated by experimental results of 400 A welding machine. The experimental results show that proposed digital waveform control scheme is applicable for different wire feeding speed conditions, and the welding process is stable and the welding bead appearance is good.