Influence of the rotor angle precision in control of interior permanent magnet synchronous machine drives and improvement method using sensorless estimator with Hall sensors

Abstract

This document studies torque degradation of an internal permanent magnet motor due to an incorrect rotor angle measurement when low rotor angle resolution sensors are used. The performance of the control with different rotor angle resolution is also analysed to determine the torque error due to the use of an incorrect synchronous rotating reference system. To address torque degradation due to the low resolution of Hall sensors, a new method of estimating the rotor angle is proposed that incorporates the information from Hall sensors. In this way, good resolution is achieved, allowing the machine to be controlled over a wide speed range even with rated torque. This method is validated through simulations and real experiments.