A New Cuk Converter with High Step-Down Ratio and its Control

A new Cuk converter with high step-down ratio was proposed. The operating principle and operating mode of the new Cuk converter were analyzed in detail and the EL model of the new Cuk converter was established. Based on passivity-based control theory, a passivity-based controller of the new Cuk converter was designed by the method called damping injection. The controller can enable the new Cuk converter achieve good dynamic and static performance and robustness to the load. Compared with Buck converters, the new Cuk converter has a higher step-down capability and a smaller ripple of the input current. Simulation results show that the new Cuk converter is feasible.