逆变交流弧焊电源输出变极性过程

Varible polarity process of inverter AC arc welding power source

设计的逆变交流弧焊电源输出变极性过程是极其快速变化的动态过程。测量这样的电流电压信号,用分流器变换电流信号,用无感电阻分压变换电压信号。设计了3个实验方案,相应地测量了变极性过程的电流电压波形。在比较分析的基础上,得出的结论是:逆变交流弧焊电源二次逆变正反极性控制驱动信号之间设置2μs死区时间最为合理。按照该方案控制,电源输出变极性过程时间为零,变极性之后输出电流电压值最大,有利于ACPMIG电弧变极性之后再引燃。

The varible polarity output process of the inverter AC arc welding power source we designed is a very quickly alternating dynamic one.The signals of current and voltage are obtained respectively by transfering them with ammeter shunt and non-inductor resistance.Three experiments are designed in which the waveforms of current and voltage in the alternate polarity output process are measured.Based on the experiments,the conclusion is drawn that it is reasonable to set a2μs dead time between driving signals of inverter AC arc welding during positive and negative polarity period.According to the above scheme ,the time of the polarity alternation is almost zero and the value of voltage after it is the largest,which is very helpful to the reignition of AC PMIG arc after polarity alternation.