Impedance Characteristics Modeling of a Two-Terminal Active Capacitor

Conventional capacitors contribute to a considerable scale of system level size, cost and failure, and suffer from one or more issues on energy density, cost, and reliability. A two-terminal active capacitor, which has the same level of convenience as passive capacitors, is proposed recently to overcome the above issues. In this paper, the modeling of the active capacitor is investigated and a voltage feed-forward compensation scheme is proposed for overshoot reduction. Therefore, the impedance, equivalent capacitance, ESR, and ESL, of the active capacitor can be specified. A case study based on a single-phase full-bridge rectifier with an active capacitor demonstrates the theoretical analyses.