Thermal Design and Optimization of Harsh Environment Power Electronics in Natural Convection Heat Transfer

A study of thermal management of a harsh environment power electronics system is presented. The thermal environments were found to be between 65 °C and 90 °C that is considerably higher than many traditional electronics applications. A modular, low cost, and passive air-cooling system was desired. An analytical model was developed to obtain the heat transfer characteristics. Further performance verification of the thermal management solution was completed using a commercially available CFD tool. A small footprint area for thermal design of the power electronics connected with an electrically isolating low-conductivity material to the heat sink increased the challenge. A further thermal performance enhancement was achieved with the addition of a heat spreader between power electronics and the heat sink, and optimization of the heat spreader was achieved by utilizing FEM technique.