Thermal analysis of outer rotor type IPMSM using thermal equivalent circuit

According to miniaturization, estimation of motor temperature is necessary, and many approaches are developed. In this paper, temperature estimation of interior magnet synchronous motor (IPMSM) is conducted. Heat source of the IPMSM considering core losses of rotor and eddy current loss of PM is applied the thermal equivalent circuit network. And thermal resistance and thermal capacitance is considered. For verifying the thermal equivalent circuit, heating test is conducted to obtain the reliability of thermal analysis. And transient and unusual state is analyzed due to changing of load and speed.