Initial Rotor Position Estimation for Wound-excited Doubly Salient Machine Based on Line-to-line Flux Linkage Method

Based on the finding that the line-to-line flux linkage of wound-excited doubly salient machine (WEDSM) varies with the rotor position, a new method to estimate the initial rotor position without any pulse injection is proposed. This method detects the line-to-line flux linkage to determine the sector where the rotor locates in the building-up procedure of the excitation field. The drawbacks, including cogging torque ripple and magnetic saturation and asymmetry have effect on the accuracy of the estimation. And the effects are analyzed in detail. Further simulations and experiments verify the feasibility of the proposed method.