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In order to improve the efficiency of feature extraction of mechanical vibration signal of circuit breaker and the reliability of state recognition of circuit breakers, a mechanical fault diagnosis method of high voltage circuit breaker based on XGBoost is adopted. Firstly, 17 time-domain features are extracted from the measured vibration signals of circuit breakers, constructing feature vector and the separability of eigenvectors is analyzed. Then the feature vector is input into XGBoost, the depth and size of the tree are optimized to realize the high reliability discriminant analysis of the mechanical state of circuit breaker. Experiments on vibration data of circuit breakers prove that, this method has high efficiency in feature extraction and the overall recognition accuracy is high.

The historical data of peak load for electrical bus are limited and fluctuated violently. The fluctuation ability of peak load for electrical bus is nonlinear and randomly. So its prediction accuracy is low. In order to improve the accuracy of peak load forecasting for electrical bus, a peak load forecasting for electrical bus method based on limited historical data under complex weather conditions is proposed. Firstly, the influence of natural meteorology, society and other factors on peak load fluctuation for electrical bus is analysed; Secondly, based on the reduction of redundancy between features of potential feature set, the feature importance ranking is obtained by conditional mutual information (CMI). Then, according to the improved particle swarm optimization extreme learning machine suitable for small sample training, the forward feature selection is performed to determine the optimal feature subset. Finally, based on the optimal feature subset, the optimal peak load forecasting model is established.