Research On High Step-up Converter Topology With Active Coupled Inudctor

As the industry is developing,the renewable sources have attracted widely attention.The part of the renewable sources,however,produce a lower output voltage,leading to a hard connection with subsequent stage,research of high step-up dc converter topology has becoming a significant project.On the basis of predecessor study,this paper proposes a kind of proportional type and inverse type active coupled inductor high step up dc converter.Then,by combining with three level idea,three level high step-up dc converters with proportional type and inverse type are decued.Last,the inherent connection between impedance source dc converter and high step up dc converter,a series of high step up dc converters are developed.This paper mainly studies active coupled inductor high step-up dc converter topology,includes following reasearch content.First,based on the research of Z source network and dual Boost converter,this paper proposes active coupled inductor network,constructing active coupled inductor network high step up dc converter.Then,this paper studies the connection ways of windings of coupled inductor and connection type between the winding connection point and external components,constructing quasi active coupled inductor network high step up dc converter topology.Last,the generalised coupled inductor network is proposed and a series of dc/dc converter topologies are deduced.Meanwhile,aiming at the problem of leakage inductance,the introduction of clamped circuit not only supresses the votlage spike across switch but also transfers energy existing in leakage inductance,promots the efficiency.Second,this paper studies the relation of voltage gain and turns ratio in coupled inductor high step-up converter,and proposes single switch inverse type coupled inductor Boost converter.Then,based on the former,a novel inverse high step-up dc converter with(50)type coupled inductor network is introduced.As the turns raio is smaller,the gain becomes larger.In addtion,design guidelines of the coupled inductor is optimized.In order to increase the flexibility of gain implementation,after combining the characteristic of proportional type and inverse type,a novel high step-up dc converter with ? type coupled inductor network is introduced.The proposed converter has both inverse and proportional characteristics.Third,on the basis of traditional coupled inductor network high step-up dc covnerter,this paper intrduces the three level idea,namely,by changing the connection type,constructing clamped voltage source of switch,reducing voltage stresses across switch and capacitor and doubling pulse frequency of current through inductor,optimizing the whole performance of converter.Based on the former sections,this paper proposes three level proportional high step-up dc converter with active coupled inductor network through shifting of switch and construction of clamped voltage source.Subsequently,this paper proposes three level inverse high step-up dc converter with(50)type coupled inductor network.The proposed converter has not only three level characteristic but also inverse characteristic.Lastly,this paper studies the existing drawback of impedance source network dc converter,deduces a series of dc converter with impedance source network for high step-up application,and reveals the connection between impedance source dc converter and high step-up dc converter.In addition,for the introduction of three level idea in the high step up dc converter,this paper also deduces a series of three level dc converter for high step-up application.