Enhanced voltage-boost inverter and rectifier

In this paper, an enhanced voltage-boost (EVB) converter is presented for use in both dc-ac power inversion and ac-dc power rectification. If desired, the converter can also perform buck power conversion, rendering it as a buck-boost converter with the unique ability of generating a much higher voltage transfer gain than other traditional converter topologies. Analyzing in details, it is shown that the converter uses three distinct switching states for waveform generation, effectively giving it two independent degrees of control freedom for fine-tuning its transfer gain. The durations and relative placements of these switching states can also be optimized for minimizing charge ripple variation within the dc EVB LC network, which in turn prolongs the lifespan of electrolytic capacitors and enhances the converter output waveform quality. When implemented physically, the converter can conveniently be controlled using a generic hardware configuration consisting of a low-cost digital signal processor with an on-chip pulse-width modulator and a digital programmable logic device. The resulting digitally controlled converter is lastly tested in simulation using PSIM with Matlab/Simulink coupler and experimentally using a laboratory prototype configured as either a dc-ac inverter or ac-dc rectifier.