Adaptive Variable Switching Frequency Digital Controller Algorithm to Optimize Efficiency

An adaptive digital controller with maximum efficiency point tracking to optimize DC-DC converter switching frequency is presented in this paper. The Adaptive-Frequency-Optimization (AFO) method changes the DC-DC converter switching frequency while tracking the converter minimum input power (maximum efficiency) point under variable conditions including variable load and variable input voltage. The AFO digital controller continuously finds the optimum switching frequency that will result in the minimum total loss while converter parameters and conditions vary. In this paper, the AFO method is discussed analyzed and its digital control algorithm and experimental implementation are presented.