Light-load efficiency improving algorithm in cascaded buck-boost converter

The loss reduction algorithm for the light-load is needed to increase overall efficiency. The inductor current ripple is the fixed magnitude, and it generates almost loss of the total losses at the light-load. Therefore, the ripple current reduction algorithm is efficient method to increase the light-load efficiency. This letter proposes the control algorithm to increase light-load efficiency by controlling the inductor current ripple. To control the inductor current optimally, a detail analysis of the system and a maximum efficiency control scheme are progressed. From the proposed algorithm, the efficiency is increased about 2.93% at the 10% load condition compared with the conventional algorithm.