An Enhanced Control Algorithm for Improving the Light-Load Efficiency of Noninverting Synchronous Buck–Boost Converters

摘要

A loss reduction algorithm at light loads is needed to increase the overall efficiency of noninverting synchronous buck–boost dc–dc converters. Inductor current ripple generates most of the total loss at light loads. Thus, a ripple current reduction algorithm is an effective method of increasing light-load efficiency. This letter proposes a control algorithm for increasing the light-load efficiency by controlling the inductor current ripple. To achieve the optimal control of the inductor current, a maximum efficiency tracking scheme is implemented. Experimental results verify that the proposed algorithm significantly improves the light-load efficiency; at a 10% load condition, the efficiency is approximately 3.19% higher than that of the conventional algorithm.