A MULTILEVEL CONVERTER WITH REDUCED NUMBER OF SWITCHES FOR FUEL CELL POWER CONDITIONING SYSTEM

This study investigates the potentials of cascaded five and seven level converters with reduced number of switches for fuel cell power conditioning system. Fuel cells is one of the most important sources of distributed energy because of its high efficiency, high energy density, plus high reliability and long life due to few moving parts. This study proposes a suitable multilevel converter with less number switches that fulfills the required performance specifications of a fuel cell power conditioning system. The dc-dc and dc-ac converters are required to produce constant magnitude and frequency voltage from fuel cells. However Switching losses in these converters reduce overall efficiency of the system. To improve the efficiency and to use in medium and high power applications, the multilevel converter with reduced number of switches is connected as dc-ac converter. To synthesize maximum levels at the output voltage, the proposed topology is optimized for various objectives, such as the minimization of the number of switches, gate driver circuits and capacitors and blocking voltage on switches. The operation and performance of the proposed multilevel converter have been evaluated by MATLAB/SIMULINK.