Unidirectional Asymmetric Hybrid Nine-Leg Rectifier With Floating H-Bridge Capacitors

This article proposes a unidirectional cascaded topology of a power rectifier. It is composed of a three-leg cell with half-controlled legs series connected with one H-bridge cell per phase. The dc links of the H-bridge cells operate with floating capacitors. The floating capacitor voltages regulation is solved by means of the common-mode voltage manipulation. Control and pulsewidth modulation strategies are presented to regulate the capacitor voltages and grid currents. The design of passive elements is also shown. The topology has its harmonic distortion content, semiconductor losses, and average switching frequency values compared to those of conventional solutions. Experimental results validate the proposed topology and strategy.