基于恒导通时间控制的负载自适应大功率LED驱动电源设计

发布时间：2018-02-09 02:46

本文关键词： 大功率LED 负载自适应 PFC LLC ZVS　出处：《武汉轻工大学》2015年硕士论文　论文类型：学位论文

【摘要】：本论文在分析大功率LED的工作原理与特性的基础上,对大功率LED驱动电路的基本组成和工作原理进行了探讨。在对不同类型驱动电路进行分析之后,提出了基于SSL4120T芯片的大功率LED驱动电路。该电路方案以SSL4120T为核心,其AC-DC级在升压拓扑结构的基础上,采用恒导通时间控制法、使电感电流工作在临界导通模式(Critical-conduction Mode,简称CRM)来实现功率因数校正(Power Factor Correction,简称PFC)。DC-DC级选用半桥谐振变换器(Half-bridge LLC Resonant Converter,简称HBC或LLC)与同步整流,通过LLC谐振变换器,原边功率管可以实现零电压开关(Zero Voltage Switch,简称ZVS),副边进行同步整流,以减小整流损耗提高系统的工作效率。该电路在课题研究期间开展的主要工作如下:(1)设计系统结构,选择控制芯片;(2)对PFC技术进行研究与分析,选择适合本项目的控制方法;(3)对LLC电路进行理论研究,建立FHA等效模型,设计谐振变压器;(4)设计同步整流器;(5)制作驱动电源样机,对其各项性能指标进行测试,验证理论分析的正确性。
[Abstract]:On the basis of analyzing the working principle and characteristics of high-power LED, this paper discusses the basic composition and working principle of high-power LED drive circuit. A high power LED drive circuit based on SSL4120T chip is proposed. The core of the circuit is SSL4120T, the AC-DC level is based on the boost topology, and the method of constant on-time control is adopted. The inductance current works in critical conduction mode (CRM) to realize power factor correction (PFC) Factor correction. The half-bridge resonant converter Half-bridge LLC Resonant converter (HBC or LLCconverter for short) and synchronous rectifier are used in the PFC).DC-DC stage, and the LLC resonant converter is used. The primary side power transistor can realize zero voltage switch zero Voltage switch, the secondary side carries on the synchronous rectification, in order to reduce the rectifier loss to improve the system working efficiency. The main work of this circuit during the research period is as follows: 1) Design the system structure. Select control chip to study and analyze PFC technology, select the control method suitable for this project, do theoretical research on LLC circuit, set up FHA equivalent model, design resonant transformer, design synchronous rectifier, design synchronous rectifier and make a prototype of driving power supply. The performance indexes are tested to verify the correctness of the theoretical analysis.
【学位授予单位】：武汉轻工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN312.8;TM46

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