| Summary: | 碩士 === 中原大學 === 電機工程研究所 === 99 === ABSTRACT
This thesis uses Single-Stage Flyback topology to build a multi-string light-emitting diode (LED) driver, with the advantages of isolation, high power factor (PF), high efficiency and low cost. The light-emitting diode lighting system is a multi-string LED driver with minimum components.
In this thesis, the novel cascade current sharing technology is implemented by using “protel 99” to design the prototype circuit and then using IC LD7591 controller to drive two strings of LED. With our cascade current sharing technology, we can achieve equitable distribution of current in each LED string. In addition, we verify the validity of our technology by “ISSPICE” simulation software and determine the parameters of all components and increase system performance. Therefore, it can save a lot of time and provide proper components. Experimental results show that “Novel Cascade Current share technology” can achieve the advantages of fewer parts and simpler circuit to complete multi-string LED driver design.
The contributions of this thesis include three parts:
1.Combine single stage with current sharing: In our proposal, we combine PFC single stage topology with multi-string LED current sharing technology. It simplifies the structure of LED driver. The LED drivers can driver multi-string LED just only “one stage”. This Technology can substantially reduce development cost and time.
2.Reduce power loss: Single-stage design can reduce a lot of components, so that it reduces the power losses. Because current transmission by components will cause conduction loss, more components will cause more losses.
3.Get a result of smaller size: Fewer components make lighting system lighter, thinner and cheaper. Our proposal reaches a goal that the system size is smaller than others. Small size can reduce the installation space and can make it more convenient to install, and can possibly make solid-state lighting (SSL) more popular in our daily life.
|
|---|
