Inductor design for high-power applications with broad-spectrum excitation

The design of high-power inductors for applications with broad current spectrum excitation is a challenging task. The resonant inductor of a resonant DC-link inverter (RDCLI) is one such example. The inductor current consists of a resonant current component, a DC component, which supplies the active power to the load and a modulation component, which depends on the modulation strategy. In addition, the frequency and amplitude of the dominant current components change with operating point. Conventional inductor designs for single-frequency excitation do not perform well in broad-spectrum applications. In order to improve these designs, the impact of broad current spectrums on winding design, core selection, power density, and thermal-handling capability must be investigated. In this paper, alternate inductor topologies, which better address the above issues, are proposed and investigated.