Research on Arc Model of Disconnector for Conduction Interference of Electronic Transformer

When disconnector operate capacitive small currents, it will produce strong high frequency transient electromagnetic interference, which will cause damage to electronic transformer. In this paper, a dynamic arc model of disconnector is established. by using TACS element in ATP-EMTP. Referring to the standard GB/T 1985-2014, the test circuit of disconnector switch operation is established. Combining with the dynamic arc model, the maximum current amplitude of high frequency transient electromagnetic interference is 576A, the maximum voltage amplitude is 1.8p.u, and the transient current frequency is up to 210kHz. The corresponding experimental circuit is established, and the waveform of high frequency voltage and current generated by disconnector operation is obtained. By comparing the measured and simulated transient waveforms, it is found that the transient current and voltage changes are in accordance with each other, which verifies the correctness of the arc model.