Thermal Investigation of Power Supply Module (QDR-PSM) for Space Application Using Numerical and Experimental Approach

摘要

Power supply module is designed to provide input power to digital system and radio frequency system for space application. High power and package density in electronics are continuously increasing, which create more heat in the system. Thermal management in space application is even more challenging since the cooling of these systems primarily relies on conduction and radiation by ignoring convection for space application. The effective heat removal from a component and PCB to mechanical housing is through conduction and partly with radiation. In fact, thermal design in electronics through thermal modelling and simulation is becoming an integral part of the electronics system design process because it is normally less time consuming and also low expensive compared to the experimental cut-and-try approach. In paper, thermal design, analysis and testing of DC-DC power supplies module have been explained in detailed. Thermal analysis has been carried out using computational fluid dynamics technique, by considering total heat dissipation of 40 W. Thermal model was created using Ansys Icepak, and all active and highly dissipating component are modelled. Conduction and radiation mode of heat transfer are considered during the analysis by maintaining the base plate temperature at 55°C. Based on the analysis results, the convertor has been manufactured, assembled and electrically tested. Thermal testing has been carried out at ambient air temperature of 25°C for identifying the hot spot in the convertor using thermal camera before it is tested at high temperature. Thermal cycle testing of space grade DC-DC convertor is performed in thermo vacuum chamber at extreme cold temperature of negative 15°C and extreme hot temperature of 55°C under 1 × 10~(-5) torr pressure condition, during which electrical functionality of the module is monitored and temperature of active component is measured and the results of the thermal analysis and testing are elaborated and compared.