An Energy Storage Oscillating Wave Test System for Accurate Partial Discharge Detection in Power Cables

ABSTRACT To address the issues of low noise and lack of portability in on‐site partial discharge (PD) detection and testing of cables, the paper will present an AC excitation cable oscillation wave detection system using a capacitor bank power supply of energy. By adding two bidirectional high‐speed solid‐state switches at the output end of the inverter power supply in the traditional frequency modulation series resonant circuit, this paper uses capacitor banks to generate the required oscillation wave voltage, with the advantage of no switching noise interference. At the same time, to avoid pulse interference caused by the generator and reduce the sensitivity of PD detection, the following measures are taken in this article: using capacitor banks for power supply during the testing phase; the test interval utilizes mains power to charge the capacitor bank. This solves the problem of the system's dependence on the generator. After conducting high‐capacity capacitance tests and 10 kV distribution cable application tests, the results showed that under the condition of capacitor bank power supply, the system can achieve equivalent 1 μ. The load of the F cable has increased to a peak of 24 kV, and the noise level of PD detection is below 10 mV. This indicates that the system in this article meets the requirements of offline PD detection tests for 10 kV power cables.