On-line detecting of rotor bar breaking based on wavelet digital filter and instantaneous power

A new approach based on spectrum analysis of feature instantaneous power is proposed to detect the rotor bar breaking faults in this paper. Similarly with the definition of instantaneous power, feature instantaneous power is still the product of a sampled line voltage and the corresponding line current. The difference is that the current used to define the feature instantaneous power has been filtered out the fundamental component which can produces the constant weight. Compared with the familiar way based on spectrum analysis of the instantaneous power, the proposed approach can get rid of the interference to the fault related characteristic components from the constant weight. The validity of this approach has been verified by theoretical analysis and simulation results.