Substituting And Inserting Method Of Construction And Application Of Power Electronic Converters

Wide gain DC/DC converters used in a grid-connected solar PV system or a fuel cellsystem and long-lifetime AC/DC converters used to drive LEDs have become an interestingresearch topic due to the rapid development of renewable energy, green energy and lightingenergy-saving technology. The existing ways of construction of power electronic convertershave a lot of randomness. And they are time-consuming, manpower-consuming andproperty-consuming since they are based on empirical method. Sometimes the empiricalmethod can not help construct a converter with practical values. Therefore, studying asystematic and repeatable method of construction of power electronics converter topologieshas theoretical and practical significance.Based on the structural characteristics of power electronic converter topology andpackaging and merging principles of TRIZ, the method of substitution and insertion, which issuitable for construction of power electronics converter topology, is proposed in thisdissertation. Then, a series of wide-gain DC/DC converters, bridgeless AC/DC converters andelectrolytic-capacitor-less LED driving circuit are derived by employing the proposedmethods.Firstly, the method of substitution is studied and used in the construction of wide gainDC/DC converters. Dual-inductor cell and switching-inductor-capacitor cell are introduced inthis dissertation. Two wide gain Buck-Boost converters and a high gain N-times Boostconverter are proposed by using the proposed two basic cells to substitute the inductor in theconventional Buck-Boost and Boost converter. This method can also be extended toconstructing wide gain Cuk, Sepic, Zeta converters.Then, the method of insertion is presented and employed in the construction of wide gainDC/DC converter. Three passive cells and some inserting methods are introduced. ASepic-Boost converter, a novel high gain converter with voltage-multiplier, a novel quadraticBuck-Boost converter, two other high gain converters based on coupled inductor andvoltage-lift are proposed by applying the inserting method.Furthermore, the methods of substitution and insertion are used in the construction ofnovel bridgeless AC/DC rectifiers. A bridgeless Boost-Buck-Boost rectifier, apseudo-continuous boost-Buck-boost rectifier and a bridgeless Buck-Buck-Boost rectifier areproposedFinally, a novel LED driving circuit without electrolytic capacitor is proposed byemploying the methods of substitution and insertion to prolong the lifetime of LED driving source.The aforementioned studies demonstrate that the proposed methods of substitution andinsertion are of good practical value and can be used to help deduce novel power electronicconverters.