Summary: | This study analyzes the recovery voltage changes when a low-voltage circuit breaker opens with load and short-circuit faults and explains the reignition types under different recovery voltages. Reignition probability models of a single-pole contact and three-pole contact under different reignition types are established. The variation law of the contact erosion amount with the arc starting phase angle is analyzed. The distribution characteristics of the electrical life under three reignition types are obtained by simulating the low-voltage circuit breaker electrical life with a random arc starting phase angle. The results show that the electrical life of contacts obviously decreases after reignition, and that the electrical life changes differently with different reignition types. Specifically, the electrical life of a single-pole contact and three-pole contact is reduced by different degrees for the same reignition type. Hence, the influence of reignition on the electrical life distribution characteristics of a low-voltage circuit breaker cannot be ignored.
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