Research On High Step-up DC-DC Converters

In the modern industrial applications, always need to use boost converters. Fortraditional boost converters, as a result of the limitation duty ratio,it often onlysuitable for the applications which is not more than five times, so when people needhigher voltage gain, it requires to find another way to solve the problem. Research onhigh step-up ratio converters meet the requirement of the industries, such asautomobile headlights, solar system and storage battery applications. This topicreview of the industry demand for high step-up ratio DC-DC converter, proposed ahigh gain DC-DC converter for two-stage photovoltaic system.Comprehensive research of high step-up ratio DC-DC converters develop statusat home and abroad have been done in this paper,and paper have analyzed theadvantages and disadvantages of multiple work topologies in details. Quantitativecomparison has been done between high voltage gain boost converters which allbased on the technology of coupled inductor. Coupled inductor with doubledcapacitor cell boost converters topology is chosen as the final research emphasis ofthe article. After analyzed the influence of the leakage inductance of the transformer,determined the parameters of the basic topology, and then verified its open loopfeasibility based on Saber simulation tool, and obtained the bode diagram of theopen-Loop transfer function by the tdsa module, realized the close loop by thecompensation network with double zero points and double poles. Some extensionresearches have done based on the high gain DC-DC converter with coupled inductorand doubled capacitor at last and obtained a new interleaved boost converter,simulation was completed to verify its feasibility.In this paper, the simulation and experiment have verified the feasibility of highstep-up ratio DC-DC converter with coupled inductor and doubled capacitor. Theexperiment result shows that have well boost capacity. The converter has showed itsfast dynamic response ability when the load switching, and it can obtain outputvoltage quickly and smoothly. Output powers of the converter between100W to500W efficiency were both above92%and the efficiency can reach95%when itmore than300W, the efficiency up to96.8%at about300W.