With the widely use of powerelectronicdevice the problem of harmonic distortion in power system becomes ever more important.
随着电力电子装置的广泛应用，电力系统的谐波问题日益突出。
2
By linking the DC relay contactor with powerelectronicdevice, the DC hybrid switch apparatus without switching arcing was designed and accomplished.
采用直流开关电器与电力电子器件相结合方式，设计并实现了能够实现无弧通断的直流混合开关电器。
3
Because advances electrical machinery's control to the ships is realized through the switching of electric powerelectronicdevice, massive harmonics is produced then.