Magamp post regulation for LLC series resonant converter with multi-output

Strategy of time-sharing is adopted in LLC resonant converter with multi-output for increasing the adaptability of the very topology to such application as multi-output with requirement of high regulating ratio, meanwhile strategy of magamp post regulation is applied by adding two saturable inductors in secondary output ends as well. Principle of influence generated by dead time of magamp involved in LLC resonant converter on regulating ratio, is analyzed in detail. That influence of problem of dead time existing in magamp in flyback converter is much worse than in LLC resonant converter is verified both by principle analysis and experimental result. An experimental prototype of 310 V input, 24 V/3 A and 12 V/2 A outputs, whose full load efficiency reaches 88.5%, is built to verify achievement of ZVS at full range and the wonderful cross regulating ratio.