Inductance calculation by relative permeance for the IPMSM design

When we design an IPMSM, we start with the output and the voltage equations of the machines. The output equation has two terms which are magnetic torque and reluctance torque. The magnetic torque is related to the electric-and magnetic-loading but reluctance torque is related to one more variable which is the difference of the d-and q-axis inductance. Therefore it is very important to calculate or estimate the d- and q-axis inductance in the design procedure. In this paper, we proposed the inductance calculation method by relative permeance. The result is reasonable to the initial design.