An Isolated Multi Input ZCS DC DC Front End Converter Based Multilevel Inverter for the Integration of Renewable Energy Sources
A new isolated current fed zero current switched (ZCS) front end dc/dc converter based multilevel inverter is proposed for multi input applications. The proposed front end converter with only two controllable switches integrates two different renewable energy sources, resulting in an advantageous compact structure and low conduction losses. The ZCS turn off is achieved in both the controllable switches with the proposed modulation scheme. The converter maintains ZCS turn off under a wide load, as well as input voltage variations by employing frequency modulation along with a variable duty ratio technique. Simple structure, soft switching, high gain, and automatic load regulation make the converter structure novel for simultaneous power management in multi input renewable energy applications. Converter operation and design guidelines have been outlined. A laboratory prototype of the proposed converter is developed and tested at 300 W power level. Simulations and experimental results demonstrate the robust performance of the converter under load, as well as input source voltage variations.
IEEE Transactions on Industry Applications