Nonlinear, discrete time control of power factor correction power converter

A method for controlling a power converter operable to receive a cyclically varying input signal, the method comprising:

• comparing, by a controller and in synchronization with the cyclically varying input signal, an output voltage of the power converter against a target output voltage, wherein the output voltage is provided at an output of the power converter and is regulated by an on-time generator;
• implementing, by the controller, a discrete-time operation level in response to a result of the comparison, wherein the discrete-time operation level comprises:
• determining, by the controller, a power deficiency of a previous half-cycle of the cyclically varying the input signal;
• and
• adjusting, by the controller, a width of an on-time pulse of the on-time generator in response to the determined power deficiency.

An apparatus for controlling a power converter operable to receive a cyclically varying input signal, the apparatus comprising:

• a discrete-time, on-time generator coupled to the power converter and operable to regulate an output voltage provided at an output of the power converter, wherein the power converter comprises a bulk capacitor coupled to the output;
• and
• a controller operable to:
• compare, in synchronization with the cyclically varying input signal, the output voltage of the power converter against a target output voltage;
• determine an output power taken from the bulk capacitor based on the comparison;
• determine a power deficiency based on the determined output power taken;
• and
• adjust a width of an on-time pulse of the on-time generator in response to the determined power deficiency.