Coupled-inductor Configurations for a High-gain, Interleaved, Hybrid Boost Converter

Interleaved boost converter has been widely used due to its current sharing characteristics and reduced input current ripple with reduced inductor size. To further improve the power density of the converter, coupled inductors are employed. This paper analyzes the operation of high gain switched capacitor interleaved boost converter with coupled inductor configuration. The coupled inductor configurations discussed are easy to implement with standard available cores. The converter is operated in Zone I, which corresponds to the highest gain and the converter possesses inherent current sharing among different phases. The coupled inductors are loosely coupled in order to keep the input as well as inductor current ripple low and to reduce the size keeping the efficiency same or more. The proposed integrated magnetics design is validated through a 2kW 4-phase hardware prototype. The net inductor volume, in case of coupled inductor with single core is reduced by 36% while the efficiency at rated power increases by 0.2% compared to non-coupled inductor configuration. Also, it is shown that the net inductor volume can be reduced upto 56% in case of coupled inductor with same results as compared to non-coupled inductors.