Inductance Linearization Region-Based Initial Rotor Position Estimation Method for Doubly Salient Electromagnetic Motor

Based on the characteristic that inductances of doubly salient electromagnetic motor (DSEM) vary with rotor position, this paper proposes a method for estimating the initial rotor position during the excitation field building. Firstly, the estimation error caused by not considering the nonlinear effect of actual inductance is analyzed when using the ideal linear inductance model to estimate position. Then, an initial rotor position estimation method based on the linearized region of actual inductance is proposed to overcome the adverse effect of inductance nonlinearity. Finally, the experiments on a 12/8-pole DSEM validate that the proposed method has higher estimation accuracy compared to existing methods.