Research On Boost-Sepic Magnetic Integrated Converter With Switched Inductors

With the increasing demand for energy and the increasingly serious environmental pollution caused by traditional fossil fuels,all countries in the world have been focusing on the development and utilization of new energy,especially for the development and utilization of renewable energy,such as wind energy,solar energy,fuel cells,etc.However,because of the low output voltage of these new energy sources,the voltage input of the next level inverter can not be met,so the DC current of the output can not be directly connected to the generatrix.It needs to be connected after the boost device is boosted.Thus,the DC/DC converter with low ripple and high voltage gain is particularly important.In order to increase the voltage gain and reduce the inductor current ripple and the volume and weight of the converter of traditional Boost and Sepic converters,in this paper an input inductor and a switch tube are shared between the traditional Boost converter and the traditional Sepic converter at the input end,then the traditional Boost converter and the traditional Sepic converter are connected in series at the output terminals and replacing the energy storage inductor in the converter with switched inductor unit.So a Boost-Sepic magnetic integrated converter with switched inductors is proposed.By replacing the energy storage inductance in the converter with a switched inductor,the voltage gain of the Boost-Sepic converter is(1+D)~2times of that of the conventional Boost converter,and is(1+D)~2 D times of that of the traditional Sepic converter.The voltage stress of the power converter is analyzed,and the voltage stress of the switch tube and the two diodes isU_o(1+D).The inductor current ripple under different coupling modes between inductors was analyzed.The best coupling method and coupling coefficient that can reduce current ripple were obtained.Using magnetic integration technology to design the magnetic integration scheme effectively reduces the inductor current ripple and the converter volume.Finally,the PISM software simulation and experimental results verify that the Boost-Sepic magnetic integrated converter with switching inductance proposed in this paper has better comprehensive electrical performance.