Study on Electromagnetic Transient of the Resonant Oscillation Wave Field Test

XPLE power cable has widely used in urban power transmission network, and its insulation condition evaluation is usually carried out by power supply company after commissioning to ensure the safety and reliability of XPLE power cable transmission line. there are many off-line insulation condition test technology of XPLE power cable, but the resonant oscillation wave field test is prefered method due to its convenience and flexibility for field test. However, the resonant oscillation wave high voltage generator uses high-speed bidirectional solid-state switch to interrupt the primary current of the excitation transformer, which will produce large amplitude transient switching overvoltage and overcurrent on the excitation transformer. This paper illustrates the transient switching voltage and current overshoot phenomenon by electromagnetic transient simulaiton, and proposes a optimization method for the switching control method of the resonant oscillation wave high voltage generator. The results of the electromagnetic transient simulaiton has shown that the transient switching overvoltage on the excitation transformer windings can be effectively suppressed.