For the main system,the conventional arc welding power s ource is essentially a rectifier load with a large capacitor,which results in s piky line current containing many harmonic components.

• 传统的逆变焊接电源对电网来说,本质上是一个带大电容的整流负载,其输入电流是一种尖角波,含有丰富的谐波分量。