The Research On Applications Of Passive Component Integration Technology In LED Driver

Since LED(Light Emitting Diode)has long lifetime,environmentally friendly and high illumination efficiency,it has been widely used in indoor and outdoor lighting.The LED driver is an indispensable part of the LED application.With the development of high frequency and miniaturization of power electronic equipment,high power density LED driver has attracted more attention and research.Firstly,this thesis analyzes the development trend of LED driver,summarizes the existing methods to improve the power density of LED driver,and points out that passive component integration technology is an effective way to improve the power density of LED driver.This thesis introduces the magnetic integration technology,PCB(Print circuit board)and FMLF(Flexible multi-layer foil)integration technology of electromagnetic integration technology.Several common FMLF architectures are listed,and the material selection of PCB and FMLF integration technology is analyzed in detail.Secondly,by using FMLF integration technology,a novel passive integrated structure I is proposed for a single-stage LED driver in this thesis.One transformer,two resonant inductors and two resonant capacitors in the single-stage LED driver are all integrated into an E-E-E core geometry,which reduces the volume and increases the power density of the single-stage LED driver.The magnetic flux analysis,parasitic parameter of FMLF and the design process of integrated structure I are introduced in detail,respectively,and a prototype of integrated structure I is built.Compared with discrete components,the volume of integrated structure I is reduced by 11.74%.The validity and feasibility of the proposed integrated structure I is proved by the simulation and experiment.Then,based on the integrated structure I,the integrated structure II is proposed by using the method of magnetic flux decoupling.The integrated structure II also integrates two resonant inductors,two resonant capacitors and a transformer in an E-E-E core geometry.It is found that compared with the integrated structure I,the volume of integrated structure ? can be further reduced.The magnetic flux analysis and the design process of integrated structure ? are introduced in detail,respectively,and a prototype of integrated structure ? is built.Compared with the integrated structure I,the volume of the integrated structure II is reduced by 20.07%.The validity and feasibility of the proposed integrated structure II is proved by the simulation and experiment.Finally,an integrated passive device is proposed for multi-channel LED driver with planar PCB integrated technique.One inductor,two transformers and four capacitors in the multi-channel LED driver are all integrate into a planar E-I core geometry,which reduce the volume and increase the power density of the multi-channel LED driver.The flux analysis and design process of the proposed integrated device are introduced in detail,respectively,and a prototype of integrated device is built.The feasibility of the proposed integrated device is proved by the simulation.