High Voltage and High Q: Capacitors in Resonant Circuits for High Power Applications

Resonant Circuits are a key building block of many interesting applications, ranging from DC/DC converters in power supplies, to Electrical Vehicle wireless charging and RF Matching circuits in high RF power applications.

We will start with a back to basics look at resonant circuits and what makes them tick and then build out from there, looking at some of these applications, and focusing on the selection of High Q capacitors to meet the dual need of increased power levels and increased efficiency, taking into account recent trends in power electronics design such as the increasing role of Wide Band Gap (WBG) semiconductors such as SiC and GaN.

Knowles Precision Devices offers a range of High Q MLCCs built with the goal of mitigating power loss. Thanks to their low ESR at high frequencies, these ceramic capacitors have low power loss and temperature rise. In addition, compared with alternative capacitor technologies MLCCs can provide a significant size reduction, leading to enhanced converter energy density.