Lightweight Heat Pipe Cooling Solution for High-Frequency Transformer in Power Electronics Building Block

Abstract The integrated Power Electronics Building Block (iPEBB) is under development for the electrification of United States Navy ships; a key challenge in this development is thermal management. This study explores the feasibility of using heat pipes in conjunction with a chilled cold plate to maintain iPEBB transformer core and coil temperatures below 100°C and 155°C respectively. First, a standalone thermal model of the transformer was built in StarCCM+ and used to test various cooling solutions. The proposed design uses 16 copper-water heat pipes configured to provide alternative paths of heat flow for the regions of the transformer furthest from the cold plate. Shapal HiM Soft Machinable AlN ceramic provides high voltage insulation. Electromagnetic simulations were used to estimate the induced losses in the heat pipes as a result of high frequency coil operations, with 18 W across all 16 heat pipes being predicted for the final design. The final configuration achieved a core maximum temperature of 99.7°C, coil maximum of 93.2°C, and MOSFET maximum of 144.6°C, all within their respective limits despite the induced losses in the copper-walled heat pipes. The usage of heat pipes adds only 0.29 kg to the weight-constrained iPEBB. The thermal results showcase the effectiveness of heat pipes in the iPEBB and invite further analysis and experimentation to validate the electromagnetic implications of the concept. These results also contribute to the general ongoing study of heat pipe usage near high-frequency electronics.