Multi-loops control design for a new Sheppard-Taylor based Power Factor Corrector with model-nonlinearity compensation

In this paper, a new nonlinearity compensation control is developed and applied for a single-phase Power Factor Corrector (PFC) based on the combination of the Sheppard-Taylor and SEPIC topologies. Compared to conventional buck, boost or buck-boost PFCs, this topology allows a better current tracking at the AC side, with a relatively reduced voltage at the DC side. Based on the exact linearization of the converterpsilas averaged model, and on the use of a fixed-frequency carrier to generate the Pulse-Width-Modulated (PWM) gate signal, the control system is designed to ensure unity power factor at the rectifier AC-side and regulated voltage at the rectifier DC-side. The performance of the proposed control scheme is tested through simulations, and evaluated in terms of source current Total Harmonic Distortion (THD), input power factor and DC-voltage regulation.