Accurate and easy-to-implement rotor position estimation scheme for sensorless control of Interior Permanent Magnet Synchronous Motor drives at full speed range

A new sensorless control scheme for interior permanent magnet synchronous motor (IPMSM) drives is presented in this paper. In this method, high-frequency low-amplitude current is injected to the stationary alpha-axis and the corresponding high frequency voltage and the injected current are used to solve for rotor position based on the mathematical model of the motor in the stationary alpha-beta frame. This method does not neglect any term in the mathematical model of the motor and therefore can estimate the rotor position accurately from standstill to the rated speed. The method solves for the rotor position in the stationary alpha-beta frame and therefore is easy to implement. The method has been verified with simulation results, which show the position estimation error of the method is from 1deg(electrical) at standstill to 4deg at the rated speed.