中大功率LED电源方案设计及应用环境研究

发布时间：2018-08-20 08:02

【摘要】：近年随着开关电源的发展,软开关技术在各类电源应用中已经非常普遍,很多高效率的拓扑我们都可以选择,主要为谐振型的软开关拓扑和PWM型的软开关拓扑。随着半导体器件的飞速发展,开关管的各项参数越来越好,尤其是导通电阻、寄生电容和反向恢复时间越来越小的情况下,为LLC谐振拓扑发展提供了一个很好的平台,谐振变换器可以实现软开关变换,可以把整机效率提高一个层面。LLC型谐振电路具有许多优点。首先,可以在输入和负载大范围变化的情况下调节输出,开关频率变化很小。第二,整个工作中,实现零电压切换(ZVS)。·最后,所有寄生元件、半导体器件的结电容和变压器的漏磁电感和激磁电感都可以实现ZVS切换。本文首先对LED光源近年发展趋势进行了简单的分析,对LED路灯需求进行了阐述,分析了以LLC半桥谐振电路为核心的LED路灯电源的优缺点和电路拓扑选择。以144W路灯电源为设计目标,设计指标输出电压为48V,输出电流为3A的LED路灯电源,对整个电源系统进行了各环节的测试及整机优化,验证了电路方案的可行性。本文第一部分介绍了论文成立此课题的前景及论文构架。第二部分介绍了目前LED市场的发展,对LED发展趋势进行了展望,并阐述了LLC谐振电路在LED路灯中的关键地位。第三部分介绍了LLC半桥谐振电路的拓扑类型和基本原理,介绍了LLC电路各种拓扑的优缺点,并对各个时间周期的工作特性和原理进行逐一阐述和分析。第四部是分简化LLC电路,分析LLC谐振电路频域直流特性。第五部简单介绍了LLC拓扑各环节的优化方案和关键元件选择。第六部分是按照设计要求,设计一款144W路灯电源,包括PFC电路设计部分和LLC半桥谐振电路部分,并对设计各环节进行说明。第七部分对整个电源系统进行了系统的测试。第八部分电源整机系统各模块损耗分析。第九部分总结了测试中发现的问题并加以解决。可以看出,144W半桥谐振电路效率优势明显,并在待机功耗等其他方面表现优良。
[Abstract]:In recent years, with the development of switching power supply, soft switching technology has been widely used in all kinds of power supply applications. We can choose a lot of high efficiency topologies, mainly resonant soft switching topology and PWM soft switching topology. With the rapid development of semiconductor devices, the parameters of switch become better and better, especially the on-resistance, parasitic capacitance and reverse recovery time are getting smaller and smaller, which provides a good platform for the development of LLC resonant topology. The resonant converter can realize the soft switching transformation, and can improve the efficiency of the whole machine by one layer. LLC type resonant circuit has many advantages. First, the output can be adjusted in a wide range of inputs and loads, with little change in switching frequency. Secondly the zero-voltage switching (ZVS).) is realized in the whole work. Finally all parasitic elements semiconductor device junction capacitance and transformer leakage inductance and exciting inductance can realize ZVS switching. In this paper, the development trend of LED light source in recent years is simply analyzed, and the requirement of LED street lamp is expounded. The advantages and disadvantages of LED street lamp power supply with LLC half-bridge resonant circuit as the core and the circuit topology selection are analyzed. Taking 144W street lamp power supply as the design target, the design index output voltage is 48V, output current is 3A LED street lamp power supply. The whole power supply system is tested and optimized in every link, and the feasibility of the circuit scheme is verified. The first part of this paper introduces the future and framework of the thesis. In the second part, the development of LED market is introduced, the development trend of LED is prospected, and the key position of LLC resonant circuit in LED street lamp is expounded. The third part introduces the topology types and basic principles of LLC half-bridge resonant circuit, introduces the advantages and disadvantages of various topologies of LLC circuits, and expounds and analyzes the working characteristics and principles of each time cycle one by one. The fourth part is a simplified LLC circuit, the LLC resonant circuit frequency domain DC characteristics. In the fifth part, the optimization scheme and the selection of key components of LLC topology are introduced briefly. The sixth part is to design a 144W street lamp power supply according to the design requirements, including the PFC circuit design part and the LLC half-bridge resonant circuit part, and explain each link of the design. The seventh part has carried on the system test to the entire power supply system. The eighth part is the loss analysis of the whole power supply system. The ninth part summarizes the problems found in the test and solves them. It can be seen that the 144W half-bridge resonant circuit has obvious efficiency advantages and good performance in other aspects such as standby power consumption.
【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

【共引文献】