Research On High Gain DC-DC Converter Of Coupled Inductance Voltage Doubling Unit

With the global promotion of new energy,especially the widespread application of photovoltaic power supply systems,many universities and research institutes have conducted a lot of research on improving the voltage gain and efficiency of DC converters,among which non-isolated high-gain DC/ DC converter has always been one of the research hotspots.In this study,the coupled inductor voltage doubling unit is used to improve the voltage gain of the DC converter.Based on the analysis of the transformer equivalent model of the coupled inductor,two types of coupled inductor doubling units,the peer and heterogeneous stages,are proposed.A series of high voltage gain DC converter topologies based on coupled inductance voltage doubling units are obtained by applying the peer-stage and heterogeneous-stage coupled inductance voltage-doubling units to Boost converter and double Boost converter respectively.For one of the heterogeneous-stage CLC coupled inductance voltage doubling unit Boost converter and double Boost converter,a detailed study is carried out respectively,the operating modes and performance of the two converters are analyzed,and the voltage gain and the main components are given.The voltage stress is verified by simulation.The results show that the boost converter and the double boost converter of the heterogeneous-stage CLC coupled inductance voltage doubling unit have good electrical performance,but the leakage inductance in the coupled inductance will resonate with the parasitic capacitance of the switch when the switch is turned off,which would cause large impact on the voltage of the switch.In order to solve the effect of leakage inductance on the switch tube,a kind of clamp capacitor circuits is proposed to absorb the energy of the leakage inductance in the coupled inductor,thereby reducing the voltage impact on the switch tube.Applying the proposed clamping capacitor circuit to Boost converter and double boost converter of heterogeneous-stage CLC coupled inductance voltage doubling unit,topologies of the Boost converter and the double Boost converter topology boost transformation of a kind of heterogeneous-stage CLC coupled inductance voltage doubling unit with clamping capacitor are obtained.One kind of boost converters and double boost converters of heterogeneous-stage CLC coupled inductance voltage doubling unit clamped to ground is studied in detail.The working modes and performance of the two converters clamped to ground are analyzed.The voltage gain and voltage stress of the main devices are simulated and verified by experiments.The test results of the experimental prototype show that the clamping capacitor can effectively absorb the energy of leakage inductance in the coupled inductor,and effectively improve the electrical performance of the boost converter andthe double boost converter of the heterogeneous-stage CLC coupled inductor voltage doubling unit.The correctness of the theoretical analysis and simulation is verified.There are 61 pictures and 91 references in this paper.