Mechanical defect detection of SF6 high voltage circuit breaker using wavelet based vibration signal analysis

High voltage circuit breaker is a device that requires frequent maintenance. This leads to high cost and time consuming. If the internal component of circuit breaker can be inspected without any disassembly. The period of the maintenance can be extended. This paper proposes the method of indirect internal component inspection. The experiment was applied with 110 kV SF₆ puffer-type circuit breaker with hydraulic operating mechanism. The defect circuit breakers were tested. Then the vibration signals were recorded. The analyzing of vibration signal in time domain is difficult for the detection of small defect. Using wavelet transform, the detection of small defect can be performed. This detection reduces the risk of the failure in operation of circuit breaker.