Y-connected three-leg converters applied in three or four-wire shunt compensator

This paper investigates a power shunt filter composed by three standard three-leg converters, acting in three or four-wire system. Compared with the usual three-phase shunt filter, the proposed converter permits reducing the dc-link voltages, the harmonic distortion or/and the switching losses and being fault tolerant. Suitable control strategies to adjust the filter and circulating currents as well as the three dc-link voltages are presented. The PWM strategy is designed to command the converter according to the reference voltage solicited by the controllers. Simulation and experimental results are presented.