Experiments on Capacitive Current Interruption with Air-Break High Voltage Disconnectors

Capacitive current interruption with air-break disconnectors in a high-voltage network is an interactive event between circuit and arc with a variety of interruptions and re- ignitions. In order to investigate this transient phenomenon, a series of interruption tests was performed at KEMA High Power Laboratory. In this paper, a brief analysis of the interruption process is presented and is compared with experimental data from the test. Typical wave shapes of voltages across the capacitances, disconnector and current through the disconnector are given. Re-ignition voltage and energy input to the arc on re- ignition are also investigated. Comparison shows that the test data are in good agreement with simulation. It is concluded that besides higher interruption current and higher power supply level, a lower ratio between source side and load side capacitance leads to more severe interruption and longer arc duration. In the end, the actual status of IEC recommendations on testing, that has taken into account this arc-circuit interaction, will be discussed.