Simulation of pressure relief valve movement in the compression volume of a self-blast interrupter

Recently, the self-blast principle of extinguishing the arc by the blast pressure which is generated by the arc itself has been widely applied to the high voltage circuit breaker. In the self-blast principle, the pressure relief valve fitted on the piston is opened to release excessive pressure in the compression volume during high current interruption. The design of the pressure relief valve operation is important for the performance of self-blast interrupter. Practically, the pressure relief valve is actuated by spring force and designed to open when the overpressure becomes greater than the designated operating pressure difference. In this paper, the actual pressure measurement result of the compression volume to understand the movement of the pressure relief valve are presented. The analytic model which describes the movement of the pressure relief valve are proposed, and the effects of different pressure relief valve models are analyzed by gas flow simulation tools.