Induction motor saliencies analysis using zero-sequence signal injection

This paper presents an analysis of the magnetic saliencies in induction machines based on the injection of a zero sequence carrier. This way of injection allows evaluating those components of the admittance matrix which are not usually considered in the literature. The injection of the zero sequence carrier can easily be implemented, does not perturb the current control and the evaluation of its response is simple. It requires, however, access to the neutral point of the machine. The use of the zero sequence carrier for induction machines is a new approach that is evaluated in this paper. Experimental tests showed that two saliencies can be clearly identified in the carrier response: one due to the rotor bars and other due to the saturation in the main flux path. This would allow to estimate both, the rotor position and flux angle.