Equal Loss Distribution in Duty-Cycle Controlled H-Bridge LLC Resonant Converters

The duty-cycle control is a popular option for current limiting in LLC resonant converters. Such required to protect the converter either during start-up or an overload. Although this method proved be effective, switching and conduction losses of are increased because modified waveforms tank. Hence, safe operation, it vital distribute between switches symmetrically. However, conventional phase-shift modulation methods do not provide naturally. This letter elaborates on that was proposed different soft-switching topology more than decade ago solve problem, adaptable emerging dc transformers. Furthermore, simple implementation shown equal distribution validated experimentally. VHDL code with modulator attached available openly reuse.