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《IEEJ Transactions on Electrical and Electronic Engineering》2017,12(6):925-935
In this paper, we report a novel single‐switch AC to DC step‐down converter suitable for light emitting diodes. The proposed topology has a buck and a buck–boost converter. The circuit is designed to operate in the discontinuous conduction mode in order to improve the power factor. In this topology, a part of the input power is connected to the load directly. This feature of the proposed topology increases the efficiency of power conversion, improves the input power factor, produces less voltage stress on intermediate stages, and reduces the output voltage in the absence of a step‐down transformer. The theoretical analysis, design procedure, and performance of the proposed converter are verified by simulation and experiment. A 36 V, 60 W prototype has been built to demonstrate the merits of this circuit. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
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基于反激变换器的无频闪LED驱动电源 总被引：1，自引：0，他引：1
为解决具有功率因数校正(PFC)功能的发光二极管(LED)AC/DC驱动电源存在的工频闪烁问题,提出了一种Flyback-Buck LED驱动电源。它由一个双输出绕组反激(Flyback)PFC变换器和一个Buck变换器构成,Flyback PFC变换器的辅助绕组作为Buck变换器的输入,Buck变换器的输出与Flyback PFC变换器的输出串联。通过Buck变换器有效补偿二次工频纹波,消除了LED频闪。Flyback-Buck大部分功率只经Flyback PFC单级变换,与两级变换拓扑相比,该拓扑具有较高的效率。最后,通过一台0.7 A/50W的实验样机,验证了理论分析的正确性。 相似文献
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单级功率因数校正变换器中的低频不稳定现象研究 总被引：1，自引：1，他引：0
研究了由Boost 变换器和Forward变换器级联构成的单级功率因数校正(power factor correction,PFC)变换器中的低频不稳定现象。通过数值仿真观察了系统随着输出功率增大时出现的低频振荡现象及其对输入电流总谐波畸变的影响。根据Forward变换器电感电流导电模式的临界条件得到了相应的稳定性边界,并对低频不稳定现象的边界碰撞分岔本质进行分析和讨论。通过实验研究,验证仿真结果。该文的研究有助于更好地理解单级PFC变换中的动力学行为,对该系统参数设计也具有一定的参考价值。 相似文献
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伴随着大功率发光二极管(LED)户外路灯照明的大量应用,迫切需要研究具有成本低廉、可靠性高、多通道输出实现容易等特点的LED驱动电源.根据路灯照明LED驱动的特点,对临界导通电流模式(BCM) Boost+电流型并联谐振半桥的两级拓扑结构驱动电源的输出级进行了改进,增加了整流、滤波、开路过压保护和负载自动检测等功能,设计了一款基于传统的电流型并联谐振拓扑结构的三通道准恒流输出型60W LED路灯驱动电源.实验结果表明该驱动电源适合LED路灯照明驱动. 相似文献
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用于太阳能LED路灯系统的新型双向变换器 总被引：1，自引：0，他引：1
在已有的太阳能路灯系统中,通常没有考虑发光二极管(Light Emitting Diode,简称LED)工作时蓄电池的工作状态,从而导致LED器件的使用寿命缩短,影响了整个系统的正常工作.现提出一种新型DC/DC电路,用于控制蓄电池的充放电,从而实现LED的恒流工作,保证了太阳能LED路灯系统的可靠工作.此外,它能用于光伏电池的最大功率点跟踪(Maximum Power Point Tracker,简称MPPT)控制,从而充分发挥光伏器件的效能.实验结果验证了所提方法的有效性. 相似文献
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研究了基于Zeta/Sepic双向变换器的光伏半导体发光二极管(LED)照明系统,提出一种充电控制算法,其既能实现太阳能电池的最大功率点跟踪(MPPT)又能满足蓄电池电压限制条件和浮充特性;设计一种基于HV9930控制芯片的LED恒流驱动电路.构建实验系统,测试表明,控制器可以根据蓄电池状态准确地在MPPT、恒压、浮充算法之间切换,MPPT充电效率较恒压充电显著提升,LED驱动电路恒流效果好. 相似文献
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Xiaoqun Wu Chi K. Tse Siu Chung Wong Junan Lu 《International Journal of Circuit Theory and Applications》2006,34(3):341-355
This paper describes the fast‐scale bifurcation phenomena of a single‐stage single‐switch power‐factor‐correction (PFC) regulator comprising a boost stage operating in discontinuous conduction mode (DCM) and a forward stage operating in continuous conduction mode (CCM). The two stages combine into a single stage by sharing one main switch and one control loop. Using ‘exact’ cycle‐by‐cycle computer simulations, the effects of various circuit parameters on fast‐scale instabilities are studied. The results are qualitatively verified by experimental measurements. This work provides a clear picture of how the variation of certain practical parameters can render such a circuit fast‐scale unstable. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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有源功率因数校正器(Active Power Factor Correction,APFC)是开关电源的发展趋势之一,而其中的单级功率因数校正器(Single-Phase Single-Stage PFC)由于控制简单、成本低,成为目前APFC研究的热点之一。文章针对单级功率因数校正器,介绍其优点和存在的一些缺点,并介绍几种较新的拓扑。 相似文献
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Tiesheng Yan;Hao Wen;Haogang Xia;Quanbao Tao;Guohua Zhou; 《International Journal of Circuit Theory and Applications》2024,52(3):1173-1191
Traditional multiple-output AC-DC power supply with power factor correction (PFC) function usually employs a two-stage cascaded topology that is composed of prestage PFC converter and N independent poststage DC-DC converters to achieve PFC and voltage or current regulation of N outputs. Hence, the conventional two-stage cascaded multiple-output AC-DC power supply needs N + 1 magnetic components as power inductors or transformers and N + 1 controllers, which increases the cost and size of the multioutput converters. The conventional multiple-string AC-DC LED driving circuits usually employ a two-stage topology to realize PFC and independent current regulation of each LED string. To address the issue of complexity, high cost, and large size of the two-stage multistring LED driving circuit, a single-stage triple-output Cuk PFC converter is proposed by cascading boost converter and single-inductor triple-output buck converter with sharing main power switch in this paper. The topology operation principle, control strategy, design consideration, and operation characteristics of the proposed circuit are investigated in detail. With the switch sharing and inductor multiplexing technologies at the same time, the proposed converter utilizes only single-stage converter to achieve PFC function, independent regulation of triple-channel output current, and flicker-free with low twice line frequency LED current ripple. The proposed converter is verified by a 50-W experimental prototype of LED driver for triple string LEDs. The proposed converter only uses two power inductors and a set of controller to achieve greater than 0.945 PF, up to 90.5% efficiency, low LED current ripple, and independent current regulation for triple LED strings with different forward voltage, which may significantly reduce the cost and size of the traditional AC-DC multistring LED driving circuit. 相似文献
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