Comprehensive Design and Analysis of an Interior Permanent Magnet Synchronous Machine for Light-Duty Passenger EVs

Abstract

This paper presents a detailed process for the design of interior permanent magnet synchronous machines (IPMSMs) for electric vehicle (EV) applications. First, a comprehensive design process featuring two objectives and three constraints is proposed to realize an optimal IPMSM design that can satisfy the key performance requirements for an EV application. The objectives and constraints were carefully selected and designed to obtain a balance between performance, efficiency, and cost. Because the inductances and magnet flux linkage of the machine are key design parameters for attaining optimal flux-weakening capability, the impact of the machine dimensions on these two parameters is thoroughly investigated and explained using both analytical and numerical techniques. Additional analyses including normalized key performance metrics and the impact of short-circuit faults in PM machines with three different characteristic current values (1, 1.3, and 2.6 pu) are also provided, highlighting the advantages and limitations of the three baseline designs.

Keywords

• Electric machine design
• electric vehicle (EV)
• finite element analysis (FEA)
• flux-weakening (FW)
• interior permanent magnet synchronous motor (IPMSM)
• traction motor