For inductance calculations, it is important that the end effects in the PMs and the end-winding inductance, i.e., Le in (3), are taken into account. Le is calculated using the methods
presented in [21]. For accurate simulation, the d-q inductances are obtained from a 2-D or 3-D finite-element (FE) analysis. Although these inductances are shown to vary during different
load conditions caused by saturation and cross-coupling effects, they are taken as constant to simplify the dynamic modeling. The torque generated by the slip PMG and that by the PMSG
are given, respectively, by