DC-DC 컨버터의 효율 향상을 위한 연구

Abstract

This thesis presents a method of analyzing conduction losses of Single Ended Primary Inductance Converter (SEPIC). The proposed method introduces new formulae to determine the current on each circuit component by using duty factors, input voltage, and output load resistance of SEPIC which can be conventional or Direct-linked SEPIC (DLSEPIC) converter. DLSEPIC converter is a recently proposed high-efficiency SEPIC converter which has conduction loss as a one of the largest power losses. The proposed formulae were calculated on the same voltage conversion ratio in the conventional SEPIC or DLSEPIC while the duty factors of direct-linked period (DS2) were 0.25, 0.5, and 0.75. The fact that the main power loss reduction is on the inductor L2 was proved by the calculated conduction losses

these values in DLSEPIC were 36, 11, and 2% of those in conventional SEPIC converter when DS2 were 0.25, 0.5, and 0.75, respectively. The tendencies of power conversion efficiency versus output load variation were verified to be same by the results of proposed formulae and experiment.