Study On Wide Input Boost Converters

For the application of renewable energy systems, such as fuel cell and photovoltaic (PV) cell, step-up dc-dc converters with high voltage gain are required. Many research works have been reported on the switching converters with high voltage gain.Cascade converters can increase the voltage gain of the switching converters, however, it increases cost and affects the efficiency of the switching converters. The quadratic boost converters can increase the voltage gain by using only one switch to obtain quadratic dc gain, it simplifies the control circuit design, however, it may present voltage or current overstresses when voltage gain is high. The Luo converters and positive output super-lift converters can also obtain high voltage gain and reduced switch voltage stress by using voltage-lift-technique, so by applying the traditional voltage lift cell to quadratic boost converter, improve the steady state characteristics of quadratic boost converter, but when the voltage gain is high, the reduce of switch voltage stress is not obviously.Based on voltage-lift-technique, a modified voltage-lift cell is proposed and analyzed, which can further improve the voltage gain and reduce the switch voltage stress of boost converter. The operation principle of the proposed voltage-lift cell is analyzed. Compared with traditional voltage-lift cell, the voltage gain of converter with the modified voltage-lift cell is higher, and the switch voltage stress of converter with the modified voltage-lift cell is much lower.In order to get a converter with reduced switch voltage stress and high voltage gain, the modified voltage-lift cell is applied to quadratic boost converter. A single-switch high gain quadratic boost converter is obtained which further improves the voltage gain and reduces switch voltage stress over the quadratic boost converter and the other single-switch high gain converters. The small signal model of quadratic Boost converter based modified voltage-lift cell is build by using the state-space average method.Based on the traditional voltage-lift-technique, in order to reduce the inrush current of the switch, a resonant voltage-lift cell is proposed. A single-switch high gain boost converter is obtained by applying the resonant voltage-lift cell to quadratic boost converter. The operation principle of the proposed quadratic boost converter with resonant voltage-lift cell is analyzed. Experimental results are presented to verify the theoretical analysis results.