Fast thermal analysis of an ISG in hybrid electric vehicle drive system

Due to the space size of the vehicle itself and vehicle energy capacity constraints, hybrid electric vehicles (HEV) usually use high power density and high efficiency permanent magnet synchronous motor (PMSM) as the integrated starter/generator (ISG) motor of drive system, but the temperature rise caused by the losses in the process of running will lead to some problems. It is necessary to obtain the temperature distribution accurately of the motor. In this paper, a nine nodal point thermal resistance network is established by choosing the key parts of the motor according to the motor structure. The mathematical model is established. Finally, the transient characteristics of the temperature field are obtained. By comparing to the thermal analysis of the motor performed by finite element simulation, the reliability of the results is verified, results show that thermal resistance network method have great advantages on thermal analysis of motors.