Dynamic Heat Generation Modeling and Thermal Management of Electromechanical Actuators.

摘要

The heat loads in an electromechanical actuator (EMA) and an electronic unit (EU) are highly transient and localized in nature; therefore, thermal management systems (TMS) designed for time-averaged, uniform heat loads of an EMA and EU are inadequate. The heat loads of EMAs must be accurately determined and managed if EMAs are to be used as replacements to current hydraulic actuators. This report presents a dynamic heat generation model and a thermal model for a permanent magnet motor and power drive. The input to the model included a flight mission profile and an environmental temperature profile, along with the key parameters unique to the EMA. From the cases studied, it could be concluded that the heat generation profiles are indeed highly dynamic, and the major barrier to heat removal from the motor is external to the motor. Strong forced convection is needed. The model compared well with the detailed finite element analysis. The model was also used to compare its temperature predictions with temperature measurements of the motor and power drive provided by the Air Force Research Laboratory. Though the agreement was good, due to the low heat load associated with the test cases, the model could not be validated conclusively.