Estimation of interruption performance in high-voltage circuit breakers with a modified method for arc parameter evaluation

Interruption performance of high-voltage circuit breakers has been quantitatively evaluated through current zero measurements during interruption tests. The interruption capabilities of the circuit breakers are able to be estimated by means of an arc model calculation. The parameters of the arc model are determined through the current zero measurements. In order to simulate more precisely the success or failure of current interruption, a modified extraction method of arc parameters is proposed in this paper. The arc parameters are calculated by combining an equivalent circuit calculation and a non-linear least square fitting for current zero measurement data. The arc model calculation with the modified extraction method of arc parameters is applied to the development and design of an actual high-voltage circuit breaker. The capacitance required for 80 kA interruption can be estimated based on the current zero data measured during 50 kA interruption tests. The test results of interruption and failure agree well with the predicted performance. The proposed method consisting of the arc parameter extraction from current zero data and characterization of the parameters as the function of arc time constant can evaluate short-line fault interruption performance in high-voltage circuit breakers.