Abstract: Control circuitry uses modified average current mode control to regulate average current through an inductor of a power converter. Control circuitry uses modified average current mode control to regulate average current through an inductor of an active power filter. Control circuitry uses average current mode control to regulate average current through an inductor of an active power filter. This average current mode control negates modulation of the average inductor current. In this way, output ripple current of the power converter does not have a significant effect on the input current drawn by the power converter.

Abstract: An active-power filter includes control circuitry to combine an integrated output-voltage feedback signal, an input-voltage sense signal and an output-load feedforward signal to generate a control signal. An output-load subsystem draws the output current from the active-power filter and the output-load feedforward signal indicates when current drawn by an output-load subsystem changes. In some embodiments, the output-load subsystem may draw output current from the power converter having an output current ripple at a nominal frequency, which may range, for example, between about 35 and 100 Hz. The control circuitry may include an integrator to integrate the output-voltage feedback signal. The integrator may have a control loop bandwidth significantly less than the nominal ripple frequency to loosely regulate the output voltage while the input current drawn by the active-power filter is tightly regulated.