To realize multi-signal joint diagnosis in circuit breaker's state evaluation methods,and to improve their evaluation accuracy,we proposed an intelligent evaluation model of circuit breaker mechanical properties based on multiagent system.Taking a circuit breaker which has mono-stable permanent magnetic operating mechanism as the example,its model involves four kinds of signals: auxiliary contact,operating mechanism current,travel of the contact,and mechanical vibration.Detailed analyses on the evaluation agent's architecture and the process of the system's multiagent evaluation and ratiocination were also proposed.Moreover,it is proved by three application cases that the proposed method could accurately evaluate circuit breaker status not only with normal signals,but also in certain signal failure situations;meanwhile the model has a strong self-learning ability.
Based on vibration signal of high voltage circuit breaker,a new method of intelligent fault diagnosis that wavelet packet extracts energy entropy which are used as characteristic vector of the support vector machine(SVM)to construct classifier for fault diagnosis is presented.The acceleration sensors are applied to collecting the vibration data of different states of high voltage circuit breakers based on self-made experimental platform in this method.The wavelet packet are fully applied to analyze the vibration signal and decompose vibration signal into three layers,and wavelet packet energy entropy of each frequency band are as the characteristic vector of circuit breaker failure mode.Then the intelligent diagnosis network is established on the basis of the support vector machine theory.It is verified that the method has a better capability of classification and a higher accuracy compared with the traditional neural network diagnosis method through distinguishing the three fault modes which are tripping device stuck,the vacuum arcing chamber fixed bolt looseness and too much friction force of the transmission mechanism of circuit breaker in this paper.
YANG ZhuangzhuangLIU YangZHOU GuomingLIN XinJI TianLI Bin
