Study On Quadratic Switching DC-DC Converters

With the development of new energy, the technology of using new energy requires switching DC-DC converters have wider input voltage range. A way to broaden rang of voltage transfer ratio is using the technology of cascading switching DC-DC converter. Quadratic switching DC-DC converter is a kind of cascading converter. Quadratic switching DC-DC converter realized the cascade of converter with one switch, which improve efficiency of the converter and reduce the drive circuit.The quadratic buck converter is researched as an example in this thesis. The working process of quadratic buck converter in continuous conduction mode (CCM) and discontinuous conduction mode (DCM) are analyzed. The state-space averaging (SSA) equivalent model of quadratic buck converter is established. The method of selecting quadratic buck converter’s parameters is analyzed. Finally, Simulation and experimental results are presented to verify the theoretical analysis and the state-space averaging equivalent model.The voltage control quadratic buck converter is researched as an example in this thesis. The steady-state and transient response of the quadratic buck converter in this control method is analyzed. Voltage control buck converter and voltage control quadratic buck converter are comparative analyzed.A nonlinear control technique, pulse train (PT) control technique of switching dc-dc converters in discontinuous conduction mode (DCM) is used to control quadratic buck converter in this thesis. The steady-state and transient response of the quadratic buck converter in PT control technique is analyzed.