Short-term dielectric recovery property of breaking for artificial zero current-limiting vacuum circuit breaker

摘要

In order to research influences of di/dt on breaking capacity of vacuum switch in the process of direct-current interruption at the time of clearance between open contacts, arc time, and current zero, recovery strength of intrinsic dielectric after breaking of vacuum switch was measured, which is free recovery process of contact clearance dielectric without applying recovery voltage. A short-term dielectric recovery property of breaking for artificial zero current-limiting vacuum circuit breaker was proposed in this study. The breaker comprises superconducting current limiting module and direct-current zero passage breaking module. Breaking feasibility of the superconducting current-limiting direct-current breaker under different nominal voltage was researched. There is a critical separation in the breaking process of direct current under the test condition. Faster breaking speed and shorter arc time were selected in the scope of separation so as to improve the recovery strength of intrinsic dielectric for electrode gap after current zero passage. Lower inverse current zero passage frequency was selected under the same separation and the same arc time so as to improve the recovery strength of intrinsic dielectric after current zero passage.