Nonlinear Current Control of Single-Phase PFC Suitable for Mixed-Signal IC Implementation

New nonlinear current control methods are developed for single-phase power factor corrected (PFC) AC-DC converters. The control methods combine input current feedforward with partial feedback control based on the switch current to achieve sinusoidal input current and unity input power factor. The nonlinear control methods don´t suffer from the limitations of conventional linear (average) current control in terms of control bandwidth and sensitivity to noise. The resulting current control performance is superior to all existing single-phase PFC control methods, and can meet the requirements of various applications, including high-frequency (360-800 Hz) airborne power systems. The control methods are also ideally suited for integrated mixed-signal implementation, requiring an analog current controller that is very simple, insensitive to noise, and independent of converter and control design parameters, and a digital controller that operates with a sampling frequency much lower than the switching frequency. A prototype design is presented to validate the analysis and to demonstrate the performance of the control methods