For many deficiencies that exist in induction motor rotor bar broken
faults and stator winding faults diagnosis, a method based on instantaneous power
decomposition via wavelet packet was introduced. By analyzing the instantaneous
power decomposition and characteristic of the faults frequency, the double faults
model was built. The node characteristic of faults frequency was extracted using
wavelet packet, and the faults were diagnosed using the node rate. Simulations show
that the instantaneous power decomposition includes rich information about the
double faults, and the wavelet packet analysis can easily extract the characteristic of
the faults. The RMS rate can be used to diagnose the double faults. This method is
effective, and easily to be used in engineering.