Abstract:

 The three-level DC-DC converter is known to have too many power switches and complex operation modes‚and it is difficult to obtain a unified model by using conventional modeling approaches．In view of such disadvantages‚a novel unified modeling approach‚the pulse waveform integral approach‚ was used for the first time to analyze the converter．With the unified modeling of Buck three-level DCDC converter as an example‚the modeling principle was investigated in detail．Also the unified modelng of other three-level DC-DC converters can be deduced．The simulation analysis and experiment results indicate that the pulse waveform integral approach to the unified modeling of three-level DC-DC converters is both effective and efficient．

Key words: three-level converter, unified modeling, pulse waveform integral approach, periodic pulse function