Measuring the location of saliencies in AC machines

This paper reviews techniques used for the measurement of saliencies in AC machines. The ability to measure saliencies is important because of the effect of saliencies on machine behavior. Saliency information can be used to aid or improve machine design, modeling, and analysis, as well as for sensorless control. From a review of existing measurement techniques it is shown that there are two main drawbacks to most of the published techniques for saliency measurement. First, almost all of the techniques require either a modification to the machine design and construction, or they cannot be used under normal machine operating conditions. Second, the dynamic measurement of the physical location of saliencies has not been addressed although it is important for the development of accurate models. To overcome these shortcomings, a new method of dynamically measuring the location of saliencies is presented that does not require any modification to the machine's design or construction, and does not affect the normal operation of the machine. Experimental results are presented together with detailed analysis and discussion that show some of the potential applications of the proposed technique.