Abstract
In this paper we present a method for calculating torque of a permanent magnet synchronous motor considering magnetic saturation. The proposed method uses two-dimensional numerical magnetic field analysis and dq-axes equations in which the effect of the cross-magnetizing phenomenon is included. First we calculate reactances of the permanent magnet synchronous motor at every step of changing rotor position using this method. And we consider the cause of variations of the reactances. Secondly we separate torque by factors using the results of the reactances. The findings are as follows.
(1) Numerical values of the mutual reactances between d-and q-axis Xdq are not negligible.
(2) The reactances vary according to the rotor position because the parts of magnetic saturation are different.
(3) Torque caused by magnetic coupling between d- and q-axis circuits can be calculated.
