Analysis of Luo converters with voltage-lift circuit

The voltage-lift technique using voltage-lift circuit has been successfully applied to several series of DC-DC Luo converters. However, the voltage-lift circuit definitely has an unavoidable influence on the overall converter performance. It is attempted to clarify such an effect. Four converters with voltage-lift circuit are analysed: positive output self-lift Luo converter, positive output super-lift converter, negative output self-lift Luo converter and positive output re-lift Luo converter. It is assumed that these converters operate in both continuous and discontinuous conduction modes. The converter performance in continuous conduction mode is first analysed. The boundary between continuous and discontinuous conduction modes and the modified voltage transfer gain are derived for each circuit. In addition, formulas for calculating the filling efficiency in DCM for the four converters are given. Both the simulation and experimental results verify the theoretical analysis.