Medium Voltage Vacuum Circuit Breakers Boucing Time Overall Study

Bouncing time is a complex phenomenon occurring during the closing operation phase of medium voltage vacuum circuit breakers. Bouncing, is generated by the impact between the two contacts of the vacuum interrupters. Its duration is correlated to the oscillatory frequencies of the moving and fixed stems of the vacuum interrupters and their respective contacts within each embedded pole of circuit breakers. The investigation was performed following those axes: mechanical analysis, mechanical finite element analysis, design of experiments, sensitivity study, and application on vacuum circuits breakers to check their respective models and readjust them accordingly. Main observations are reported, including factors impacting bouncing phenomenon that were identified during the design of experiment stage. Based on those findings, a new vacuum circuit breaker was developed and optimized confirming the validity and usefulness of these approaches.