Abstract
It is well known that single-phase pulse width
modulation rectifiers have second-order harmonic currents and
corresponding ripple voltages on the dc bus. The low-frequency
harmonic current is normally filtered using a bulk capacitor in the
bus, which results in low power density. However, pursuing high
power density in converter design is a very important goal in the
aerospace applications. This paper studies methods for reducing
the energy storage capacitor for single-phase rectifiers. The minimum
ripple energy storage requirement is derived independently
of a specific topology. Based on theminimum ripple energy requirement,
the feasibility of the active capacitor’s reduction schemes is
verified. Then, we propose a bidirectional buck–boost converter as
the ripple energy storage circuit, which can effectively reduce the
energy storage capacitance. The analysis and design are validated
by simulation and experimental results.
