A novel non-isolated switched inductor floating output DC-DC multilevel boost converter for fuelcell applications

This paper presents a novel non-isolated switched inductor floating output DC-DC multilevel boost converter. Non-isolated high gain DC-DC converters are essential for fuelcell applications to boost the supply voltage with high conversion ratio. Conventional DC-DC boost converter is not suitable for high gain applications because of high voltage stress and high duty cycle. The proposed converter is non-isolated floating output DC-DC multilevel converter which combines the switched inductor and voltage multiplier functions to achieve high voltage gain. 2N−1 capacitors, 2N+2 diodes, two inductor and only one switch is required to design N-level DC-DC proposed converter. In the proposed converter topology blocking voltage across each device is less; hence proposed converter can be synthesized by using low voltage devices. The main advantage of proposed topology is high voltage gain is achieved without using transformer and extreme duty cycle. The gain of proposed converter is depends upon the number of levels at the output side. The proposed converter has been designed for three levels with rated power 450W, input voltage is 24V, output voltage is 480V and switching frequency is 50kHz. The proposed converter topology is simulated in MATLAB/SIMULINK.