Department of Electrical Engineering, Sharif University of Technology, Tehran, Iran


Resolvers, as magnetic position sensors, are increasingly used in motion-control systems. Due to electro-magnetic structure, they preserve more accurate and reliable operation than optical encoders in stressful conditions. Usually, to evaluate the performance of a resolver, total harmonic distortion (THD) of output signals is calculated. In this study, by using analytical expressions, it is shown that THD of output signal is not a reliable indicator of the performance of a resolver.