Stability issues of boost PFC converters under different feedback compensations

Average-current-mode control allow better input current waveform; the inductor current is sensed and filtered by a current error amplifier whose output drives a Pulse-Width-Modulation (PWM) modulator. In this way the inner current loop tends to force the inductor current to follow the created reference current which is composed from the feedback voltage and the Root-Mean-Square (RMS) value of the input voltage. Therefore, if this feedback voltage is distorted, the reference current and so the Power-Factor-Correction(PFC) converter current will be distorted. This clears the important of designing the feedback parameters. In this paper, the different kind of feedback compensation will be studied and their effect on the total system stability will be cleared. Stable and unstable region. swill be made clear for design procedure.