A power converter can include a DC-DC converter stage having an input coupled to an input of the power converter and an output coupled to an output of the converter and an active power buffer coupled to the output of the power converter. The active power buffer can further include an energy storage capacitor and one or more switching devices selectively coupling the energy storage capacitor to the output of the power converter so as to alternately store energy in and discharge energy from the energy storage capacitor. Control circuitry of the power converter can include a first control loop that operates the DC-DC converter stage to regulate an average voltage across the energy storage capacitor of the active power buffer and a second control loop that operates the one or more switching devices of the active power buffer to regulate an output voltage of the power converter.