HighScape - Modelling tools to evaluate innovative cooling solutions (D3.4)

As electric vehicles (EVs) become more powerful and compact, keeping their electronic components cool is more important than ever. One of the main challenges is cooling down the SiC MOSFET, which heats up significantly during operation. If not properly managed, this heat can damage the electronics and reduce the vehicle’s lifespan.

To address this, a new cooling solution is studied: combining traditional heat sinks with Phase Change Materials (PCMs). These materials absorb a lot of heat as they melt, helping to prevent overheating during short bursts of high power, e.g. during accelerating. Once temperatures cool down, the PCM solidifies and gets ready to absorb heat again. This process is a form of thermal energy storage.

A surrogate model was developed to predict how a PCM-based cooling system behaves. This model uses a network of thermal nodes with thermal resistances and capacitances. It takes into account how heat flows through different parts of the system, including aluminium structures, PCMs, and coolant flow.

To make sure the model was accurate, a lab setup was built that mimics the conditions inside an EV. Heaters simulate the heat from the electronics, and thermocouples track how temperatures change in different parts of the system. The model’s predictions closely matched the experimental results, proving the model can reliably forecast how the system performs in real-world scenarios.

By improving the design further, for example by increasing the amount of PCM stored in the heat sink, the PCM heat sink showed even better cooling performance under more realistic power cycles. This approach allows for lighter and more efficient cooling systems, which are vital for the future of electric vehicles.

In short, this deliverable demonstrates that PCMs can provide a smart, compact, and reliable solution to managing heat in EV power electronics, and the modelling tool developed can guide the way to better and faster designs.