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This paper introduces a new method based on wavelet packet analysis and neural network theory to solve the mechanical faults of high voltage circuit breakers. Firstly, the vibration signal is decomposed after removing noise at three levels, and the integral energy of each junction is calculated. Secondly, 8-dimension characteristic vectors are constituted with the ratios of 8 sub-band energy to total...
Based on the theory of wavelet packet for signal analysis, a new method to diagnose mechanical fault for circuit breakers is presented. Firstly, vibration signal after noise removing is wp-decomposed at the fourth level, and the signal of each junction at the fourth level are reconstructed; Secondly, the characteristic vector is extracted with the proportion of envelope energy of each two junctions...
In this paper, the basic principle of support vector machine is introduced firstly, Then a new method to diagnosis fault for high voltage circuit breakers is presented based on the introduction of wavelet packet and characteristic entropy. The new method decomposes vibration signals with wavelet packet, and extracts entropy parameters from the restructured signals at the third level. Finally, the...
This paper introduces a new method to design expert system reasoning with CPLD for fault diagnosis. Firstly, the reasoning process of normal expert system is analyzed; Secondly, the knowledge and experiences of experts are transformed to binary or multi-valued reasoning using fault tree, and the processes are realized with simple gate circuits; lastly, the new scheme is used in fault diagnosis for...
In this paper a new method to extract characteristic parameters from vibration signals of HV CB (circuit breakers) is introduced based on wavelet packet. For one normal signal, the method splits each reconstructed-signal envelope into 15 segments with the same energy, at the third layer of the wp-decomposition, and the testing signal is also split with the same breakpoint as the normal signal. The...
As an effective method for diagnosis reasoning, fuzzy reasoning is hard to meet the real-time challenge for its complex process and time-consuming. Traditionally, using software to implement fuzzy reasoning need to consume much more time, so a new method to design expert system fuzzy reasoning with FPGA for fault diagnosis is presented in this paper. In the new method, fuzzy operating is realized...
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