A dynamically robust current control technique for boost type power factor correction circuits

This paper presents a dynamically robust current control method to synthesize a sinusoidal input current for AC-to-DC power converters with boost type topology. Under this control strategy, the inductor current and the diode current of the boost converter are fedback and combined in a special way which makes the input current of the AC-to-DC power converter stable and robust. The input current is solely determined by the reference current. When the reference current signal is derived from the sinusoidal input voltage, the input current is sinusoidal and in phase with the input voltage. Theoretical analysis is first provided. Small signal analysis shows that the current loop is inherently stable and offers faster dynamic response than the currently popular average current mode control. Large signal analysis reveals that the control system is not affected by large disturbances in supply voltage or output load. Computer simulations have been carried out and experimental prototype models have been built to verify the analysis and demonstrate the feasibility of the control strategy. A power factor of 0.998 is measured.