33 / 2022-03-03 10:41:32

Method for Judging Vacuum Breakdown Mechanism in Impulse Conditioning Process Based on breakdown waveforms

Impulse conditioning, Vacuum breakdown, Mechanism judgement

Impulse conditioning is a common and effective method to improve the dielectric strength of the vacuum gap. However, the lack of a method for judging the vacuum breakdown mechanisms during the impulse conditioning process hinders its further application in improving the voltage level of vacuum circuit breakers. For this reason, this paper proposes a method based on the breakdown waveforms to judge the vacuum breakdown mechanisms. In this paper, experiments are carried out with impulse voltage conditioning equipment. Voltage and current waveforms are measured by digital oscilloscope after passing through voltage divider and current divider respectively. Firstly, the vacuum breakdown mechanism is preliminarily judged by comparing the breakdown time with the peak time of the applied impulse voltage. For the case when the breakdown time is after the peak time of the applied impulse voltage, the vacuum breakdown mechanism is judged as pulse current induced breakdown or particle induced break-down by observing that whether there is a pulse current before breakdown. For the case when the breakdown time is before the peak time of the applied impulse voltage, the field emission current waveform is analyzed, and the vacuum breakdown mechanism is judged as field emission induced breakdown or particles induced breakdown. Finally, this paper verifies the effectiveness of the method through experiments.