Design and Simulation of a Two-Phase Interleaved Power Factor Corrector for an EV Charger

This work focuses on the design and simulation of a two-phase interleaved power factor controller for on-board chargers in electric vehicles. The power factor converter, which is the focus in this paper, is applied to improve power quality indexes and regulate the output voltage. A digital power factor controller is proposed for maintaining the output voltage, unity power factor, high power quality and achieving swift transient response under load changes. A double-loop control, which consists of a cascaded inner current loop and an outer voltage loop, is implemented digitally. The power factor controller performance is verified via detailed simulations carried-out in Matlab/Simulink using a powerful blend of a continuous-time plant model and a discrete-time controller. The controller design takes into account sampling effects and computation delay. Frequency domain analysis is applied to analyse the power stage model and tune the digital controller. Simulation results for a 6.6 kW two-phase interleaved power factor controller indicate that low total harmonic distortion, high power factor and good dynamic response and output regulation are achieved with the proposed digital control scheme. In fact, simulation results demonstrated a power factor up to 0.99 and THD of just 0.87% at 50 kHz switching frequency.