System and method for current balancing

A method for power factor correction (PFC), comprising:

• measuring N currents having different phases;
• generating (N−1) comparisons based on the N measured currents, wherein N is an integer greater than one;
• determining (N−1) time advance adjustments based on the (N−1) comparisons, respectively;
• generating N compensated versions of an input alternating current (AC) line signal based on the input AC line signal, a sinusoidal reference signal, and the (N−1) time advance adjustments, wherein the sinusoidal reference signal is synchronized to the input AC line signal in phase and frequency;
• and
• controlling PFC switching based on the N compensated versions of the input AC line signal.

A power factor correction (PFC) system comprising:

• a first pair switches;
• a second pair of switches;
• a switch controller that controls the first pair of switches using a first signal, and that controls the second pair of switches using a second signal;
• a reference module that generates a sinusoidal reference signal that is synchronized to an input AC line signal in phase and frequency;
• a compensation module that generates a first compensated AC signal based on the sinusoidal reference signal, the input AC line signal, and a first predetermined advance value, and that generates a second compensated AC signal based on the sinusoidal reference signal, the input AC line signal, and a second predetermined advance value;
• a duty cycle controller that determines a first duty cycle of the first signal based on a desired instantaneous voltage and the first compensated AC signal and that determines a second duty cycle of the second signal based on the desired instantaneous voltage and the second compensated AC signal;
• a current determination module that determines a first current corresponding to the first pair of switches and a second current corresponding to the second pair of switches;
• and
• an adjustment module that increases the second predetermined advance value when the second current is greater than the first current, and that decreases the second predetermined advance when the second current is less than the first current.