Design of V-Type Consequent-Pole IPM Machine for PM Cost Reduction with Analytical Method

Abstract

This study proposes an analytical method (AM) for V-type consequent-pole permanent magnet (V-CPM) machines to quickly determine the suitable permanent magnet (PM) volume while reducing the PM volume compared to that of the V-type interior PM (V-IPM) machine. Special air-gap magnetic flux density modeling is adopted in the AM, which consists of 4 asymmetric regions under one PM and the iron pole of the V-CPM. This specific modeling is utilized for the V-CPM topology, which has a different magnetic saturation trend from the conventional surface-mounted CPM (S-CPM). Hence, additional consideration of rotor saturation by novel method has been done compared to the previous works. To achieve average torque similar to that of the V-IPM machine, a V-CPM machine is designed by the proposed AM to have the same fundamental harmonic value of air-gap flux density. Furthermore, two conditions are considered for the V-CPM machine design to prevent unnecessary saturation and to minimize torque ripple. All the performance metrics of the designed V-CPM machine are compared with those of the other machines to demonstrate its superiority.