Analysis on the Control-Loop Characteristics of Flyback Converter with Magnetic Amplifier

자기증폭기를 이용한 플라이백 컨버터의 제어루프 특성분석

The continuing need for more compact and reliable switching power supplies have aroused a renewed interest in a well founded control technique the Magnetic Amplifier(Magamp). Magamp have some advantages of higher power density simple control circuit, good regulation, high frequency and high performance. The control method with magamp become attractive solutions for high current post regulated output applications. In this study, it is proposed that the magamp technique in flyback converters with multiple output windings. Operation principle of the proposed approach is described and a description of magamp control loop behavior is given first from a circuit level point of view. Then the focus is shifted to look at the same issue from the block diagram point of view. Experimental verifications on 50W multiple output flyback converter are conducted. Simulations and experimental results show that the proposed approach is high efficiency and voltage regulation of the auxiliary output is excellent.