Research On Squirrel-cage Asynchronous Motor Fault Integrated Diagnosis System Based On DSP

Squirrel-cage asynchronous motors as driving equipment are used widely in industry. It is significant in practice to improve the motor fault diagnosis technique. The motor fault diagnosis should be divided into signal sampling, signal processing, and fault diagnosis three stages. This paper uses the stator current signal sampling method to sample fault signal, the wavelet packet analysis to fault signal processing, and neural network algorithm to fault diagnosis. This method is realized in the DSP program. The squirrel-cage asynchronous motor fault integrated diagnosis system based on DSP is built in this paper.The stator-winding short circuits fault, broken rotor bar fault, eccentricity fault and bearing fault are firstly analyzed in detail in the case of squirrel-cage asynchronous motor based on its operational principle. The characteristic frequencies and their relevant amplitude are extracted and the inherent relations between motor faults and characteristic frequencies are presented. The fault signals of various motor faults are simulated effectively with software.This paper uses wavelet packet decomposition algorithm to realize fault signal analysis and processing. The fault eigenvectors are extracted, using logarithm fault eigenvectors extraction algorithm. This paper realize the recognition and diagnosis of three kinds of motor fault, using BP neural network model based on task decomposition. The wavelet packet-neural network fault diagnosis algorithm is presented in this paper. The feasibility of this algorithm is proved by computer simulation experiment.The ADC conversion module in the DSP samples the stator current signal. The experimental data is stored in the extended memory. DSP program realizes the algorithm above mentioned. The squirrel-cage asynchronous motor fault integrated diagnosis is realized. To overcome the drawback of the result overflow in DSP Q format data multiplication, a new compute method is presented in this paper.This paper programs PCI-1710HG multifunction card control program with Visual C++. The squirrel-cage asynchronous motor fault signal flexible simulation system is built. This system connects with the squirrel-cage asynchronous motor fault integrated diagnosis system based on DSP through voltage amplitude limiting protection circuit. The experimental result LED display output is realized. The squirrel-cage asynchronous motor fault integrated diagnosis experiment platform is built. The motor fault diagnosis experiment result proves the algorithm in this paper is feasibility.