A power control system includes a switching power converter and a power factor correction (PFC) and output voltage controller. The switching power converter utilizes a nonlinear energy transfer process to provide power to a load. The PFC and output voltage controller generates a control signal to control power factor correction and voltage regulation of the switching power converter. The PFC and output voltage controller includes a nonlinear delta-sigma modulator that models the nonlinear energy transfer process of the switching power converter. The nonlinear delta-sigma modulator generates an output signal used to determine the control signal. By using the nonlinear delta-sigma modulator in a control signal generation process, the PFC and output voltage controller generates a spectrally noise shaped control signal. In at least one embodiment, noise shaping of the control signal improves power factor correction and output voltage regulation relative to conventional systems.