Selecting DC-link capacitors in power converters

Power conversion schemes, incorporating an intermediate stage where energy is processed at DC, are used in applications from the simplest cell-phone charger to grid-tied inverters operating at hundreds of kW. A ‘DC-link’ capacitor, fitted at this point provides a low impedance path for high frequency switching currents, as well as energy storage.

In the latest post on Engineers' Insight, Adam Chidley explores the design considerations and trade-offs between cost, size and performance when selecting DC-link capacitors for inverters and drives.