Li Qiaoquan

Simulation and stability analysis of spring operating mechanism with clearance for high voltage circuit breakers

Spring Operating Mechanism (SOM) is a dynamic mechanical system to open and close high voltage circuit breaker in electric power controlling system. The dynamic characteristics of SOM are short operating time and high instantaneous speed in the process of working, which present strong nonlinear features. In order to save time and money for a new design and analysis of SOM, the dynamic model with clearance considering the contact and collision under ADAMS program is established. The result indicated that the existence of the clearance joints causes hysteresis and impact effects on velocity and acceleration of the mechanism compared to the mechanism without clearance.

Study of PSO-BP neural networks application in high-voltage circuit breakers mechanical fault diagnosis

High voltage circuit breakers is an important switchgear of the power system, and 80 percent of fault of high voltage circuit breakers is caused by mechanical failure. Considering a circuit breaker with VS1 type spring actuator as the subject, and the vibration signal under typical mechanical fault is collected. Then the wavelet packet and energy entropy are used to extract the characteristic value. A diagnosis method is proposed based on particle swarm optimization Hopfield neural network. This method to diagnosis fault mode for high voltage circuit breakers is established by analyzing vibration signals of the mechanism. The results show that the accuracy of the method to diagnosis fault mode based on PSO-BP neural network for high voltage circuit breakers is higher than the method of traditional BP neural network model, and the local minimum problem of traditional BP neural network model is prevented by using PSO-BP neural network model. The method of diagnosis fault based on PSO-BP neural network for high voltage circuit breakers is more accurate and feasible compared with traditional BP neural network.