一种原边控制的离线式小功率反激式LED照明驱动系统的设计

发布时间：2018-03-08 23:25

本文选题：反激式　切入点：LED驱动　出处：《复旦大学》2014年硕士论文　论文类型：学位论文

【摘要】：随着全球能源危机的迫近与环境污染的加剧,节能环保的观念已深入人心。由于LED照明技术具有节能、环保、寿命长、免维护、易控制等特点,LED照明正在逐步取代传统的照明成为继白炽灯、日光灯和节能灯之后的第四代照明光源。随着各国相继制定淘汰白炽灯的路线图,LED照明技术逐渐受到重视并推广。LED的伏安导电特性使得对LED适合采用恒流驱动。传统住宅照明的需求推动离线式小功率LED照明技术成为近年来国际研究的热点。本文由传统的电源变换器拓扑入手,介绍了功率级的拓扑结构和控制方法及调制技术。考虑到离线式LED照明应用广阔的特点,为了进一步减小照明系统的成本,本设计采用单级原边控制的反激式驱动拓扑。单级拓扑相对两级拓扑设计结构简单,元件成本低,但是也具有输出纹波较大和输出准确性较差的缺点。隔离式的离线式拓扑结构可以保护系统免受由线路电涌或接地回路引起的高电压和大电流的损害。原边反馈控制方式既节省了一个反馈光耦,减小了系统空间,同时磁性元件的反馈结构提高了设计的可靠性。本文提出了一种新型的可调消隐时间的前沿消隐电路。针对主要由功率管的关断延时引起的输出电流的线性调整率较差的缺点,设计了一种新型的片内自适应功率管关断延时检测电路来提高功率管的关断延时检测的准确度,进一步改善了设计灵活性,并提高了系统的线性调整率。论文完成的单级式原边控制的反激式LED恒流驱动系统,采用Chartered0.35--m工艺设计电路,变换器开关频率小于200 kHz。本文提出的新型的具有可调消隐时间的前沿消隐电路应用到驱动系统中。通过Cadence软件完成系统仿真,系统仿真的效率可达74.4%,输出功率5-13W；通过采用改进的峰值电流采样技术与内置自适应功率管关断延时检测技术,输出电流随输入电压的线性调整率由23.2%减小到小于1.2%。
[Abstract]:With the global energy crisis looming with the aggravation of environmental pollution, energy saving and environmental protection concept has been firmly established. Because LED lighting technology has the advantages of energy saving, environmental protection, long service life, maintenance free, easy to control, LED lighting is gradually replacing traditional lighting become incandescent lamps, the fourth generation lighting source after daylight lamp and energy-saving lamp as countries have developed a roadmap of incandescent lamp, LED lighting technology has been gradually extended.LED voltammetry conductive characteristics of attention and makes LED suitable for the constant current drive. The traditional residential lighting demand driven off-line small power LED lighting technology has become the focus of international research in recent years. This paper is composed of a power converter topology of traditional firstly, introduces the topology and control method of power level and modulation technology. Considering the characteristics of off-line LED lighting application, in order to further reduce the cost of lighting system, This design adopts flyback single-stage primary control drive topology. Single stage topology relative to the two level topology design has the advantages of simple structure, low cost components, but also has a larger output ripple and the output accuracy is poor. The off-line topology isolation type can protect the system from the line surge or ground loop caused by high the voltage and current of the damage. The primary feedback control mode not only saves a feedback optocoupler, reduces the system space, and feedback the structure of the magnetic element improves the reliability of the design. This paper presents a new type of adjustable front can be hidden between the blanking circuit. The output current is mainly composed of a power tube turn off delay caused by the linear adjustment rate is poor, the design of a new type of on-chip adaptive power switch off delay detection circuit to improve the power transistor turn off delay detection accuracy, a To further improve the design flexibility, and improves the linear regulation system. The single-stage flyback type LED primary control constant current drive system that uses Chartered0.35--m technology to design circuit, the switching frequency of the converter is less than 200 kHz. the proposed model with adjustable leading edge blanking blanking time circuit application to drive the system. Through the Cadence software to complete system simulation, system simulation efficiency up to 74.4%, the output power of 5-13W tube; turn off delay detection technology by using the improved sampling peak current with built-in adaptive power, output current with linear input voltage adjustment rate decreased from 23.2% to less than 1.2%.

【学位授予单位】：复旦大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TM46;TM923.34

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