Third-harmonic modulated power electronics interface with 3-phase utility to provide a regulated DC output and to minimize line-current harmonics

A novel approach to achieving nearly sinusoidal line current rectification of three-phase utility voltages is presented. The scheme incorporates two step-up DC-DC power converters to modulate the DC link currents at the third harmonic frequency. The modulated currents are then reinjected on the AC side of the diode bridge rectifier. Simulation results for a three-phase, 208 V (line-to-line), 3 kW system are presented. The sensitivity of the interface to unbalances in various system parameters is included. Results from experimental investigations on a small-scale laboratory model are presented