Research on the Influence of Harmonics on Interruption Performance of High-Voltage Circuit Breaker

In the context of the new electric power system, the large-scale access of renewable energy source and power electronic devices has led to an increase of harmonic components in the main grid. High-voltage circuit breakers, as crucial switching devices in the power system, will be influenced during their breaking performance under harmonic conditions. Therefore, investigating the breaking performance of high-voltage circuit breakers under harmonic conditions is essential for preventing the serious consequences that could arise from breaking failures. In this study, a harmonic breaking experimental platform was constructed using a synthetic circuit to simulate actual operating conditions of the power system. Through conducting breaking experiments under both fundamental frequency conditions and harmonic conditions, the influence of harmonics on arc energy and the erosion condition of contacts in high-voltage circuit breakers was analyzed. The experimental results indicate that, in comparison to fundamental frequency currents, harmonic currents cause significant fluctuations in arc voltage during the breaker interruption process. When the arcing time is same, the arc energy of harmonic conditions is higher, leading to more severe erosion of the contacts.