Thermal Analysis of Electro-Hydrostatic Actuator Driving Motors Considering Multiple Losses and Multi-Component Heat Transfer

The electro-hydrostatic actuator (EHA) is one of the important technologies in the concept of more electric aircraft. EHA driving motors have high power weight ratio and serious heat generation, while the temperature rise of the motor is closely related to its reliability. To estimate the thermal characteristics of EHA driving motors, a novel lumped parameter thermal network (LPTN) suitable for the permanent magnet synchronous motor (PMSM) is proposed in this paper. Firstly, combined with the actual configuration, the heat transfer path of multiple components in the motor is described by the network. Secondly, to reflect heat sources in the LPTN, power losses equations considering multiple heat-generating components of the motor are derived, which are described as functions of parameters such as speed and power supply frequency. In addition, temperature rise curves of the motor during operation is obtained through simulation analysis. The curves show that the temperature of each component slowly rises and eventually tends to be stable. Finally, the results obtained from the LPTN model are compared with those from the finite element analysis (FEA) to verify the accuracy of the thermal analysis.