Methods and apparatus to compensate for power factor loss using a phasor cancellation based compensation scheme

A power factor correction method for a power converter, the method comprising:

• determining, with a phase locked loop phase angle determiner, a phase angle of an input voltage of the power converter;
• calculating, by executing an instruction with a processor, and, based on the phase angle, a compensating current to compensate for a capacitive current introduced by capacitors of an input filter of the power converter;
• and
• controlling, by executing an instruction with a processor, switches of a power stage of the power converter, the controlling of the switches to cause a controlled current drawn by the power stage to be adjusted based on the compensating current, the adjusting of the controlled current to bring a power factor of the power converter closer to unity.

A non-transitory computer readable medium including instructions that, when executed by at least one processor, cause the at least one processor to at least:

• determine a phase angle of an input voltage of a power converter;
• calculate, based on the phase angle, a compensating current to compensate for a capacitive current introduced by capacitors of the power converter;
• and
• control switches of a half-bridge switching circuit based on the compensating current, the control of the switches to cause a controlled current drawn by the half-bridge switching circuit to be adjusted based on the compensating current to improve a power factor of the power converter.