In order to solve the problem of inspecting nonself-announcing fault of disconnector, a fault diagnosis method based on operating torque in the closing process is proposed. By building the multi-body dynamic model of the disconnector, the closing process is simulated and the operating torque is extracted. By simulating three kinds of faults, i.e. jamming defect, three-phase position asynchrony and uncompleted operation, the feature variations of operating torque curve under different states are analyzed, and six time-domain features, i.e. peak value, average value, variance, kurtosis, skewness and pulse factor, are extracted as the input of neural network model. The simulation results show that the method can reach a relatively high accuracy in identifying the occurrence of a fault and classifying the exact fault type, which provides a reference for the maintenance of the disconnector.

High-voltage disconnector,dynamic simulation,torque features,fault diagnosis