A high step-up multiphase interleaved boost converter for fuel cells power system

The fuel cells need the high step-up DC/DC converter with low current ripples to interface to the high voltage DC grid. A novel zero voltage switching high step-up multiphase interleaved boost converter (ZVS HSMIBC) is proposed in this paper. This new converter employs advantages of low input current ripples, high voltage step-up ratio, soft-switching operation, and low switching harmonics and noise. In this paper, the two-phase interleaved structure of the proposed ZVS HSMIBC is analyzed and researched in detail as a representative topology. The relevant conclusions also can apply to multiphase (3 and above) interleaved structure of the HSMIBC. Finally, an experimental prototype is built and test, the experimental results show that the proposed converter can operated under ZVS conditions with low input current ripples and low switching noise and harmonics. In addition, this converter can obtain high voltage step-up ratio up to 45 (mn = 8, d = 0.8) with high efficiency, and proportion of the experimental ratios to theoretical ratios is also high (not less than 0.8).