System and method for power factor correction frequency tracking and reference generation

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

• determining a period of an input alternating current (AC) line signal based on a time between rising edges of the input AC line signal;
• generating a frequency based on the period;
• generating an angle based on the frequency;
• generating a sinusoidal reference signal based on the frequency and an adjusted angle;
• and
• generating the adjusted angle based on the angle and based on a comparison of a falling edge of the sinusoidal reference signal, the period, and a rising edge of the input AC line signal.

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

• receiving an input alternating current (AC) line signal;
• determining a period of the input AC line signal based on a time between rising edges of the input AC line signal;
• generating a frequency based on the period;
• generating an angle based on the frequency;
• generating a sinusoidal reference signal based on a first trigonometric function having arguments of the frequency and an adjusted angle;
• generating a gradient of the sinusoidal reference signal based on a second trigonometric function of the frequency and the adjusted angle;
• scaling at least one of the sinusoidal reference signal and the gradient by multiplying the at least one of the sinusoidal reference signal and the gradient by a scaling factor;
• determining an error based on a difference between a time of a falling edge of the sinusoidal reference signal and a time half of the period after a rising edge of the input AC line signal;
• generating a first output by applying a gain to the error;
• generating a second output by selectively applying at least one of an upper limit and a lower limit to the first output;
• generating an angle adjustment based on an integration of the second output;
• preventing the integration of the second output when the second output is outside of a predetermined range of acceptable values;
• and
• generating the adjusted angle by adding the angle adjustment to the angle.