Independent Phase Belt Controlled Phase Pole Modulated Induction Machine for Integrated Starter Alternator Application
Integrated Starter Alternators for micro and mild hybrid vehicles require wide torque-speed characteristics. This paper reports a Phase Pole Modulated (PPM) Induction Machine (IM) to achieve wide torque-speed characteristics by implementing different pole pair combinations in a single machine. A novel concept of independent phase belt control technique has been reported in detail, which allows higher flexibility than the phase pole modulated machines reported in previous literature. In this design study a 12 leg inverter has been used to achieve 2/4/6/8/10 pole configurations of a single machine. This design reports the possibility of removing the constraint of the magnetic space phase angle difference between two consecutive phase belts of a machine to be a submultiple of or even 2 , which in turn allows fractional slots/pole for an induction machine. The proposed design has been validated using two-dimensional finite element analysis (2D FEA). Further, analytic expressions for equivalent circuit parameters of this proposed machine have been reported as well, which have been verified against FEA results.