Study on back to back capacitive current switching of 36kV vacuum circuit breaker

Back-to-back capacitive bank switching is the most severe duty among capacitive current switching duties because the amplitude of the inrush current with high frequency is very large. In this paper, 36kV back-to-back capacitive current switching tests of test duty 2(BC2) were carried out with vacuum circuit breaker. And the tests were performed with a series of separate making tests of 120 operations followed by a series of CO tests of 120 operations due to limitations of the test plant according to IEC standards 62271-100. The two types of VCB were tested with single phase and the test results were compared in terms of pre-arcing time, break down voltage distribution, contact surface after tests, contacting area, and field enhancement factor.