A high efficiency 1.8 kW battery equalizer

The design of an 1.8-kW battery equalizer is presented. The high efficiency of the design (97.4%) is attributed to the use of the noninverting, step-down extension of the coupled-inductor Cuk power converter. The standard buck converter with input filter utilized previously delivered only 900 W in the same package size and at a lower (91%) efficiency. A detailed theoretical and experimental comparison with the buck converter reveals the inherent efficiency and size advantages of the present design. The direct drive implementation is used in the Cuk converter, instead of the floating drive required in the buck converter.<
>