Cooling system design and thermal analysis of an electric vehicle's in-wheel PMSM

摘要

This paper proposes a simple though effective cooling system, which has been designed for a light permanent magnet synchronous motor (PMSM) with outer rotor topology, for an in-wheel electric vehicle (EV) application. Various thermal considerations, found in the recent literature and a large number of variables are taken into account in order to ensure that the cooling system meets the special features for this kind of motor. In this context, numerous simulations using Finite Elements Method (FEM) are conducted first, for the determination of temperature distribution at the various parts of the machine under different operating conditions. Next, an investigation of the proposed cooling system performance is done by examining some parameters, such as the coolant's inlet temperature and the corresponding flow rate. Based on these results the final specifications of the cooling system are determined. Finally, the cooling system's efficiency according to the motor's output power range is examined.