Designing high-performance, resilient power electronics involves challenges such as improving efficiency and device lifetime, meeting customer safety requirements, and minimizing cost. Due to their constituent materials, power electronics are more likely to fail in extreme environmentsósuch as high temperatures and pressures, producing devices for these conditions requires careful planning and design analysis.
Lead engineer Brice McPherson of Wolfspeed (formerly Arkansas Power Electronics International, Inc., or APEI) specializes in designing robust and high-efficiency power electronics products. He sought to create a new power package, one that would surpass industry standards for thermal management capabilities and make power modules more reliable in settings like extreme-depth drilling equipment or the surface of Venus.
Recent designs by the APEI team use wide-bandgap semiconductors to achieve stable operation at high temperatures and switching frequencies. McPherson collaborated with engineers at GaN Systems to design one power package with a gallium nitride (GaN) die that would be optimal for applications requiring medium current loads and extremely fast and efficient switching. Another of his designs, based on silicon carbide (SiC), met the need for a power package that could handle high currents and thermal loading in a very small area.
Before prototyping the new designs, McPherson used COMSOL Multiphysics® software to model the electrical and thermal performance of the power modules. He analyzed the influence of the device dimensions and properties of components, such as the base plate thickness and material properties on the current density, thermal resistance, and inductance of the package. Using numerical simulation, he was also able to analyze behavior such as temperature changes due to Joule heating.
From the analysis results he ultimately determined the best combination of materials and layout, optimizing the thermal resistance and current-carrying capacity. The final result was two options for power modules that exhibited significantly lower inductance and thermal resistance than the most common transistor on the market at the time, and a design flexible enough to be adapted for either a GaN or SiC die to allow for clean, rapid switching.
The power modules McPherson developed can be operated at temperatures over 225℃. His team is continuing to push the boundaries of current power electronics, paving the way for technology to function stably and last longer in more extreme environments. One day soon, it may be easier than ever to take electronics aboard planetary probes, or deeper into the earth.Learn More: https://comsol.com/c/3wuv