PROJECT TITLE :

A Quasi-Resonant Switched-Capacitor Multilevel Inverter With Self-Voltage Balancing for Single-Phase High-Frequency AC Microgrids - 2017

ABSTRACT:

During this paper, a quasi-resonant switched-capacitor (QRSC) multilevel inverter (MLI) is proposed with self-voltage balancing for single-phase high-frequency ac (HFAC) microgrids. It is composed of a QRSC circuit (QRSCC) within the frontend and an H-bridge circuit within the backend. The input voltage is split averagely by the series-connected capacitors in QRSCC, and any voltage level will be obtained by increasing the capacitor variety. The various operational mechanism and therefore the ensuing completely different application create up for the deficiency of the prevailing switched-capacitor topologies. The capacitors are connected in parallel partially or wholly when discharging to the load, so the self-voltage balancing is realized without any high-frequency balancing algorithm. In different words, the proposed QRSC MLI is very custom-made for HFAC fields, where fundamental frequency modulation is most well-liked when considering the switching frequency and the resulting loss. The quasi-resonance technique is utilised to suppress this spikes that emerge from the instantaneous parallel association of the series-connected capacitors and therefore the input source, decreasing the capacitance, increasing their lifetimes, and reducing the electromagnetic interference, simultaneously. The circuit analysis, power loss analysis, and comparisons with typical switched-capacitor topologies are presented. To evaluate the superior performances, a nine-level prototype is intended and implemented in each simulation and experiment, whose results ensure the feasibility of the proposed QRSC MLI..