19-09-2017, 03:45 PM
A new algorithm is introduced for the analysis of the motor current signature of induction machines operating during transients. The algorithm is capable of extracting the amplitude, phase and frequency of a single embedded sinusoid in a non-stationary waveform. The algorithm is applied to the detection of broken rotor rods on induction machines during startup transients. The fundamental component of the current, which varies in amplitude, phase and frequency, is extracted using the algorithm. The residual current is then analyzed by wavelets for the detection of broken rotor bars. This method of condition monitoring does not require parameters such as speed or number of rotor bars, is not load dependent and can be applied to motors operating continuously in the transient mode, eg wind generators or motorized valves.