一种单相弧焊逆变器的功率因数校正电路

为了进一步改善单相弧焊逆变器的电磁兼容性能力,在传统的弧焊逆变器基础上,增加功率因数校正电路。功率因数的主电路采用常规的升压电路,控制方式采用常规的电压负反馈和平均电流负反馈的双闭环控制策略;采用无损吸收电路,降低升压电路功率开关器件的应力,提高变换电路的效率,降低变换电路电磁干扰。文中讨论了工作原理,并制作5 kW弧焊逆变器。实验结果表明,变换器获得了高功率因数,大大地降低了器件的开关应力。

A power factor correct circuit for the single phase welding inverter

In order to improve the EMC(electromagnetic compatibility) of the single phase welding inverter,a single power factor corrector was developed based on the traditional welding inverter.By using a boost converter and employing the voltage feedback and average current feedback control strategy,the unity factor of the single phase welding inverter was implemented,and a passive lossless snubber circuit was used to lower the switching stress of the power switch.Hence,the efficiency of converter was increased,and electromagnetic interfering was improved.Finally,a 5 kW welding inverter was implemented,and the principle of operations was discussed.The experimental results shows that the highly power factor of the converter is achieved while the stress of switching devices is reduced significantly.