This paper analyses the physical characteristic of MOV and gives out its mathematical model by making it equivalent to inductance, resistance and diode three parts.

Its key idea is that integration of GTO with improved structure, antiparallel freewheeling diode and gate drive circuit, then connects its gate drive by low inductance.

In addition, the influence of the equivalent inductance, the equivalent resistance and time-jitters of the diode on the residual waveform of a half sinewave with attenuation is discussed.