Research On Mechanical Fault Diagnosis Of High Voltage Circuit Breakers Based On Vibration And Acoustic

High voltage circuit breaker is the key equipment of control and protection in power system, the online monitoring and fault diagnosis for which has important practical significance. In all the faults of high voltage circuit breaker, mechanical failure accounts for a sizeable proportion. Based on the existing shortcomings of mechanical fault diagnosis of high voltage circuit breaker, this paper establishes a scheme of mechanical fault diagnosis for circuit breaker, and further research is done from vibration signal diagnosis, acoustic signal diagnosis, and vibration and acoustic joint diagnosis.First of all, based on the analysis of the basic structure and mechanical failure of high voltage circuit breaker, the mechanical fault diagnosis scheme based on the joint analyze of vibration signal and acoustic signal is put forward, and the suitable vibration sensor and acoustic sensor is chosen; second, according to the thorough analysis of the characteristics of high voltage circuit breaker vibration signal, the method of feature extraction based on empirical mode decomposition of multi-stage segmental energy entropy is put forward, and typical fault of circuit breaker is test by using support vector machine; then, the distribution characteristics of acoustic and environmental noise is analyzed by bi-spectrum and hilbert-huang transform method, to get the mechanical fault frequency range of acoustic signal. The energy entropy center value calculated by clustering analysis is used to determine mechanical failure types of circuit breaker; finally, through the contrast of synchronization of vibration signal and acoustic signal, the specific environmental noise interference is eliminated preliminarily, dimension reduction of joint vector of vibration and acoustic based on principal component analysis method is conducted. The experimental results show that the vibration and acoustic joint analysis effectively improved the accuracy and practicality of circuit breaker mechanical fault diagnosis.