Weight-Minimizing Optimization of Microchannel Cold Plate in 200-kW SiC-based Traction Inverter
In this paper, a weight-minimizing optimization is adopted for microchannel liquid cold plate to cool the SiC MOSFET in 200 kW traction inverter. Firstly, the mathematical model of microchannel cold plate is derived in detail. Based on the derived mathematical model, by setting up desired geometry parameters of the microchannel cold plate, both thermal and pressure drop performance can be predicted in a short time without conducting time-consuming computational fluid dynamic (CFD) simulations. Moreover, the Pareto optimization can be con-ducted in the purpose for finding minimum weight points of microchannel cold plate without ex-ceeding systems thermal and pressure drop limitations.
Also, two different liquid flow path configurations, which are series flow path (V1 Series) and parallel flow path (V2 Parallel), are designed based on geometry parameters from optimizations. Considering the footprint area of 360 cm2, both versions of cold plate have weight less than 800 g with cost lower than $ 300/unit. Furthermore, the liquid cooling testing environment is setup in CPES to verify the accuracy of derived mathemati-cal, in other words, the thermal and pressure drop performances. Eventually, a trade-off analysis between two flow path configurations is compared and discussed. In conclusion, the V2 Parallel design is a more attractive candidate based on overall performances. The designed V2 Parallel has the thermal resistance around 0.008 °C/W and pressure drop lower than 0.4 bar at the systems maximum flow rate of 0.25 kg/s, while having for the footprint area of 360 cm2.