Multiple Restriking Voltage Effect in a Vacuum Circuit Breaker on Motor Insulation

It has been feared that steep front transient voltage, occurring when switching off a motor, would damage induction motor insulation. In order to investigate the switching surge effect for motor insulation, switching surge waveforms, in the order of several hundred ns at the restriking voltage time, were obtained from experiments and simulations as parameters of cable length, stray inductance and capacitance around the vacuum circuit breaker.