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1.
Abstract—Electrolytic capacitor is a key factor that limits the life-time of the driver in a high-power light-emitting diode (LED) lighting. This article presents a high-power LED lighting driver on a digital signal processor without an electrolytic capacitor. The driver is composed of three stage circuits. The first stage is the boost power factor correction converter to achieve a high power factor. As it does not use an electrolytic capacitor, the output voltage ripple is larger, which directly affects the overall performance of the LED driver. Consequently, it must be optimized through the second and third stages. The second stage is the two-output LLC (Double inductance and capacitance) resonant converter, which is driven by a digital signal processor. This stage provides galvanic isolation and reduces voltage. The third stage is the two-input buck converter based on digital signal processor control that reduces the low-frequency ripple generated from the first two stages. Moreover, the regulation of each LED string current is achieved at this stage. The simulation and experimental results show that this LED lighting driver can achieve a high power factor and good constant current characteristics. 相似文献
2.
无电解电容的改进型SEPIC LED照明驱动 总被引:2,自引:0,他引:2
高功率白光LED因其高光效、长寿命、环保及小体积等优点,已经引起学术界和工业界的广泛关注,有望成为第四代照明光源。通常LED照明的供电电源除了要求高效率、高功率因数、低成本外,还必须具有高功率密度。然而作为储能的电解电容不但体积较大,而且寿命短,不但影响了电源功率密度的提高而且降低了LED驱动的使用寿命。因此本文在研究分析了现有LED照明驱动的基础上,提出了一种改进型SEPIC变换器,并以此为基础,提出了一种新的LED照明驱动。该LED照明驱动以Twin-Bus Buck变换器作为LED电流调节器,改进型SEPIC PFC作为预处理级。该驱动在满足输入功率因数不低于0.96时,消除了电解电容。一台50W的SEPIC PFC的实验样机的测试结果表明了设计的合理性和可行性。 相似文献
3.
Amir Bagheran 《电力部件与系统》2020,48(6-7):682-696
Abstract The high-brightness light-emitting diodes (LEDs) require an AC/DC converter with power factor correction (PFC). The large output electrolytic capacitor, which is used to minimize the low frequency LED current ripple, degrades the operating lifetime of the LED driver. In order to increase the lifetime of an AC–DC LED driver, the electrolytic capacitor should be eliminated without significantly increasing the output current ripple. In this article, an isolated single-stage single-switch AC/DC high power factor LED driver without electrolytic capacitor is proposed in which a zeta power factor (PF) corrector is integrated with a forward converter. The detailed theoretical analysis and design procedure of the proposed single-stage PFC converter is presented. The experimental results of a 110 Vrms, 21?W prototype verify the theoretical analysis. The input PF is 0.99 in the proposed converter that complies with lighting equipment standards such as IEC-1000-3-2 for class C equipment. 相似文献
4.
Huang‐Jen Chiu Yu‐Kang Lo Shih‐Jen Cheng Yeong‐Chang Yan Hung‐Chi Lee Kuan‐Hung Wu Chung‐Yi Lin Shao‐Shih Ho Ming‐Hsiang Tseng Fu‐Hsien Huang 《International Journal of Circuit Theory and Applications》2011,39(11):1161-1175
In this paper, we study the feasibility of a single‐stage lighting LED lamp driver with low DC bus voltage. The operating principles and design considerations for the LED lamp driver in this study are analyzed and discussed in detail. A laboratory prototype has been built and tested. Using the prototype, high efficiency, high‐power factor and LED current control were achieved using a wide AC input voltage range from 90 to 270 V. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
5.
Xiaohui Qu Siu‐Chung Wong Chi K. Tse 《International Journal of Circuit Theory and Applications》2012,40(8):759-775
To emit high‐quality LED light, one or a bin of LED lamp(s) is normally driven by a PWM‐controlled constant current source to minimize device variation and achieve accurate brightness control. Powered from offline AC mains, the front‐end power converters should provide a relatively low DC voltage bus for the inputs of post‐end LED current regulators. To match the long lifetime of LEDs, the whole LED driver (ballast) should work as durably as the LEDs. However, the lifetime of the driver is usually limited by the high‐voltage electrolytic charge storage capacitors used in conventional PFC pre‐regulators. In this paper, our previously proposed resonant current‐fed isolated PFC pre‐regulator is extended to operate in discontinuous conduction mode (DCM). It allows the use of the low‐voltage storage capacitors on the transformer secondary, and therefore extends the overall lifetime of the LED lighting system. A detailed procedure for finding the expected lifetime of the low‐voltage electrolytic capacitor is given. As before, the high‐voltage stress on the main switches, which is typical in current‐fed isolated converters, is reduced substantially by taking advantage of the transformer leakage inductance necessary for resonance. Additionally, high efficiency is ensured by the use of dual non‐cascading structures. Steady‐state state‐space averaging analysis is performed for designing the converter in DCM operation. A prototype converter is built to verify performance of the proposed PFC LED pre‐regulator. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
6.
Taizhi Zhang Qinsong Qian Shen Xu Shengli Lu Weifeng Sun 《International Journal of Circuit Theory and Applications》2015,43(12):2025-2038
Here, we propose a single‐stage alternating current/direct current electrolytic capacitor‐less light‐emitting diode (LED) driver, which applies interleaving flyback topology to reduce the peak‐to‐average ratio of LED driving current. With this approach, the peak current through LEDs is reduced, so the lifetime requirement of LEDs can be satisfied for an electrolytic capacitor‐less LED driver. A new transformer with two interleaving auxiliary windings is applied to this driver. Based on this approach, compared with other electrolytic capacitor‐less LED drivers, an important advantage of this driver is that it can be easily created, without additional control circuits. We will explain the operation principle and control strategy of the proposed driver in detail and will use experimental results taken from a 24‐V 350‐mA prototype to demonstrate its performance. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
7.
Mitsuhiro Kadota Hiroyuki Shoji Atsushi Hatakeyama Keiji Wada 《Electrical Engineering in Japan》2019,209(3-4):26-34
This article proposes an LED driver that consists of a ceramic‐capacitor‐input rectifier and a buck‐boost converter. The LED driver has an advantage of long life because it does not contain any electrolytic capacitors. However, the issue with electrolytic capacitor‐less LED driver is that the ripple of the smoothed voltage becomes large due to insufficient capacitance of the smoothing capacitor. The proposed method, which uses the discontinuous current mode of a buck‐boost converter, reduces the output current ripple under such conditions. Experimental results using a 5.7 W LED driver prototype demonstrate that the proposed method reduces the output current ripple and that the percent flicker becomes 4.4%, which is smaller than the recommended upper limit of 8%. 相似文献
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9.
Kuan‐Hung Wu Huang‐Jen Chiu Yu‐Kang Lo 《International Journal of Circuit Theory and Applications》2014,42(1):96-109
An alternating‐current light‐emitting diode (AC‐LED) driver is implemented between the grid and lamp to eliminate the disadvantages of a directly grid‐tied AC‐LED lamp. In order to highlight the benefits of AC‐LED technology, a single‐stage converter with few components is adopted. A high power‐factor single‐stage bridgeless AC/AC converter is proposed with higher efficiency, greater power factor, less harmonics to pass IEC 61000‐3‐2 class C, and better regulation of output current. The brightness and flicker frequency issues caused by a low‐frequency sinusoidal input are surpassed by the implementation of a high‐frequency square‐wave output current. In addition, the characteristics of the proposed circuit are discussed and analyzed in order to design the AC‐LED driver. Finally, some simulation and experimental results are shown to verify this proposed scheme. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
10.
LED作为第4代光源具有其他光源所无法比拟的优势:高效,节能,长寿命等,但传统的LED电源驱动中因普遍使用电解电容,大大缩短了整体LED照明的寿命。为提高LED电源的寿命,针对路灯等大功率照明应用提出了一种三相无电解电容的LED驱动电源的设计方案。三相交流电作为输入,利用三相电之间的相位差,通过驱动电路并行向LED供电,使LED获得恒定的电流从而得到恒定光通量。根据叠加定理,给出了详细的理论推导和证明,并使用Matlab/simulink软件对于所提出的方法进行了仿真,仿真结果验证了该设计方案在无电解电容的情况下能够有效地驱动LED输出恒定光通量。 相似文献
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Chun‐An Cheng Tsung‐Yuan Chung 《International Journal of Circuit Theory and Applications》2016,44(11):1942-1958
This paper proposes a single‐stage light‐emitting diode (LED) driver that offers power‐factor correction and digital pulse–width modulation (PWM) dimming capability for streetlight applications. The presented LED streetlight driver integrates an alternating current–direct current (AC–DC) converter with coupled inductors and a half‐bridge‐type LLC DC–DC resonant converter into a single‐stage circuit topology. The sub‐circuit of the AC–DC converter with coupled inductors is designed to be operated in discontinuous‐conduction mode for achieving input‐current shaping. Zero‐voltage switching of two active power switches and zero‐current switching of two output‐rectifier diodes in the presented LED driver decrease the switching losses; thus, the circuit efficiency is increased. A prototype driver for powering a 144‐W‐rated LED streetlight module with input utility‐line voltages ranging from 100 to 120 V is implemented and tested. The proposed streetlight driver features cost‐effectiveness, high circuit efficiency, high power factor, low levels of input‐current harmonics, and a digital PWM dimming capability ranging from 20% to 100% output rated LED power, which is fulfilled by a micro‐controller. Satisfying experimental results, including dimming tests, verify the feasibility of the proposed LED streetlight driver. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
13.
Po‐Yen Chen Ching‐Tsai Pan Yi‐Hua Liu 《International Journal of Circuit Theory and Applications》2016,44(12):2058-2071
In this paper, a novel single stage passive ac to dc converter is first proposed for LED drivers. No controlled active switch, electrolytic capacitors and auxiliary power supply are required in the proposed LED driver. The advantages of the proposed driver include long lifetime, high efficiency and recyclability. In addition, application of the proposed quasi‐resonant circuit enables one to use much smaller capacitance and inductance for the capacitors and inductor to achieve high power factor and compact size. Theoretical analysis of the proposed LED driver is made, and some design guidelines are provided. Finally, a prototype system of 50‐W rating is constructed. Experimental results confirm the validity of the proposed LED driver. It can be seen that the proposed driver is robust to variations of input voltage, frequency and output load. The features of low cost, long lifetime, robustness and without EMI problem render the proposed driver a very attractive alternative for outdoor applications. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
14.
Huang‐Jen Chiu Hsiu‐Ming Huang Hong‐Tzer Yang Shih‐Jen Cheng 《International Journal of Circuit Theory and Applications》2008,36(2):205-210
This paper presents a high‐performance LED lamp driver with an improved single‐stage Flyback configuration. A constant current control method is used to regulate the lamp current and brightness. A laboratory prototype has been built and tested. With the prototype, high efficiency, high power factor, and constant lamp current can be achieved under different pieces of LED series connection. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
15.
Dimmable integrated CMOS LED driver based on a resonant DC/DC hybrid‐switched capacitor converter 下载免费PDF全文
Juan C. Castellanos M. Turhan Marcel A.M. Hendrix Arthur van Roermund Eugenio Cantatore 《International Journal of Circuit Theory and Applications》2018,46(8):1485-1502
This paper presents a 7.7 ‐ mm2 on‐chip LED driver based on a DC/DC resonant hybrid‐switched capacitor converter operating in the MHz range with and without output capacitor. The converter operation allows continuously dimming the LED while keeping control on both peak and average current. Also, it features no flickering even in the absence of output capacitor and for light dimmed down to 10% of the nominal value. The capacitors and switches of the LED driver are integrated on a single IC die fabricated in a low‐cost 5 V 0.18‐μm bulk CMOS technology. This LED driver uses a small (0.7 mm2) inductor of 100 nH, which is 10 times smaller value than prior art integrated inductive LED drivers, still showing a competitive peak efficiency of 93% and achieving a power density of 0.26 W/mm2 (0.34 W/mm3). 相似文献
16.
一种高可靠无源恒流LED驱动电源 总被引:1,自引:0,他引:1
针对如何提高发光二极管(LED)驱动电源的使用寿命以及可靠性等问题,提出一种新型高可靠无源恒流LED驱动电源,并对其工作原理和性能特点进行了分析。由于该电源内部不含有电解电容,因此克服了由电解电容引起的LED驱动电源与LED理论使用寿命不匹配的问题。该电源内部不含有任何有源开关器件以及相关驱动、控制电路等,因此电路简单可靠。在工频交流电压输入时,其输出电流值近乎恒定,与所接负载LED串联颗数无关。最后,制作了一台220 V工频交流电压输入,输出电流平均值为350 mA,额定输出功率为42 W的试验样机,在负载LED颗数发生变化时,其输出电流识误差在10%以内,输入功率因数接近1,效率达到93.3%,实验结果验证了理论分析的正确性。 相似文献
17.
LED 智能照明系统逐渐应用到室内照明,具有智能控制、高效节能、绿色的特点。国内 LED 智能照明系统仍不完善,存在不易控制、能源浪费、功率因数低、谐波干扰大等问题,使得 LED 照明的优势没有很好的体现出来,并阻碍其推广。对智能调光控制技术进行研究,设计单级 PFC 反激式恒流驱动电路和蓝牙调光方案,Android 智能手机作为客户端以蓝牙无线技术传输调光控制信号,对 LED 恒流驱动电路进行开关、调光控制实现智能照明,具有便捷可靠、电源转换效率和功率因数高、电流总谐波低的性能。 相似文献
18.
LED是未来照明的发展趋势,现阶段与传统光源相比LED相对较高的成本是制约其大规模使用的一个很重要的因素。因此LED对驱动电源提出了高功率因数、高效率、长寿命、小体积、低成本的要求。文中使用NCL30001设计了100W单级PFC大功率LED驱动电源在满足高功率因数、高效率、长寿命、小体积的情况下极大的降低了LED驱动电源的成本。并设计了样机给出了实验参数和结果。 相似文献
19.
Huang‐Jen Chiu Yu‐Kang Lo Yu‐Liang Lin Gwan‐Chi Jane 《International Journal of Circuit Theory and Applications》2015,43(3):307-317
This paper presents a novel cost‐effective pulse‐width‐modulation (PWM) dimming method for light‐emitting diode (LED) lighting applications. High efficiency, high power factor, circuit simplicity, and low cost can be achieved by a Flyback power factor correction converter with the studied adaptive PWM dimming method. The operation principles and design considerations of the proposed LED dimming method are analyzed and discussed. A 45 W laboratory prototype has been built and tested to verify the feasibility of the proposed scheme. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
20.
A single‐stage integrated bridgeless AC/DC converter for electrolytic capacitor‐less LED lighting applications 下载免费PDF全文
Hongbo Ma Cong Zheng Wensong Yu Jih‐Sheng Lai 《International Journal of Circuit Theory and Applications》2015,43(6):742-755
In this paper, a single‐stage integrated bridgeless AC/DC converter is proposed. As compared to its counterpart that is composed of totem‐pole boost power factor correction (PFC) cascade fly‐back DC/DC converter, the studied circuit has less components number while overcoming the limits of the totem‐pole type. Thus, it is suitable to the low‐power LED lighting applications. Furthermore, when both PFC inductors Lb and magmatic inductance Lm of the transformer TR1 operate at discontinuous current mode, the bus voltage vCB can be used to decouple the ac input and constant dc output power. Thus, the approach of increasing bus voltage ripple is employed to eliminate electrolytic capacitors and obtain long operation lifetime. Additionally, it is able to be compatible with our studied twin‐bus configuration for increasing the overall efficiency. A 50‐W hardware prototype has been designed, fabricated, and tested in the laboratory to verify the proposed converter validity. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献