Design and Simulation of Dielectric Recovery Testing Circuit

The DC power system has become a promising solution for future power systems due to its advantages in renewable energy and improving grid stability. However, in DC systems, short-circuit currents have a significant increase rate and amplitude; At the same time, the current lacks a natural zero crossing point. Therefore, DC disconnection has become a major issue that urgently needs to be addressed in the development of distribution systems. The DC circuit breaker based on vacuum arc extinguishing chamber is one of the most important equipment in the DC power system. Among them, the medium recovery process of the vacuum arc extinguishing chamber has a decisive impact on the reliability of the circuit breaker. In order to measure the dielectric recovery ability of vacuum arc extinguishing chambers under high current, this paper designs relevant experimental circuits, mainly including two parts: high current occurrence and forced zero crossing, as well as pulse voltage occurrence. The principle and working process are analyzed. In addition, the effects of various circuit parameters on the amplitude, rise rate, and dielectric recovery process of discharge current were compared horizontally, and the optimal circuit parameters were obtained for practical experiments. Research has found that through reasonable parameter selection, the experimental circuit can achieve the expected functions well, laying the foundation for further research on the vacuum medium recovery process in the future.