共查询到18条相似文献,搜索用时 515 毫秒
1.
2.
3.
4.
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
5.
6.
7.
《电工技术学报》2016,(23)
电解电容是影响AC-DC LED驱动电源寿命的主要元件,因此,消除电解电容技术是长寿命LED驱动电源的关键技术。将Flyback变换器与Buck变换器集成,提出一种无电解电容LED驱动电源拓扑结构,其具有较高的拓扑集成度,且控制方式易实现。通过将输入功率pin和输出功率po分为pinpo和pinpo两种情况,避免了整机能量的二次变换,通过第三端口的储能电容充电和放电平衡pin和po之间的低频脉动功率。分析了该拓扑结构的工作原理及开关模态,详述了主电路关键参数的设计思路和要点,并给出了简单易实现的控制电路。最后通过一台原理样机验证了该方案的正确性和可行性。 相似文献
8.
《中国电机工程学报》2017,(12)
为了消除LED驱动电源电解电容对其寿命的影响,研究无电解电容LED驱动电源技术具有重要意义。基于LED驱动电路输入功率pin、输出功率po和储能电容三个能量端口之间的功率流特性,讨论了三端口变换器(three-port converter,TPC)无电解电容LED驱动电路拓扑的构造原理。以此提出了基于反激(Flyback)变换器的组合型TPC拓扑族,通过集成组合型拓扑中并联子电路结构的方式得到集成TPC拓扑,并给出了适用所提TPC拓扑的主电路控制策略和简单易实现的控制电路方案。最后,搭建13.5W实验样机,验证了所提TPC无电解电容LED驱动电路的正确性和可行性。 相似文献
9.
10.
《中国电机工程学报》2017,(5)
电解电容是限制AC/DC LED驱动电源寿命的主要元件,因此,消除电解电容是长寿命LED驱动电源的关键。将两个反激(flyback)变换器集成(integrated dual flyback converter,IDFC),提出一种双反激集成无电解电容LED驱动电源结构。该结构具有较高的拓扑集成度,控制方式容易实现。通过将输入功率pin和输出功率po分为pin?po和pin?po两种情况,避免了整机能量的二次变换,通过储能电容的充电和放电,平衡pin和po之间的低频脉动功率。详细分析该拓扑结构的工作原理及开关模态,给出了主电路关键参数的设计思路,最后通过实验验证该方案的正确性和可行性。 相似文献
11.
Hongbo Ma Jih‐Sheng Lai Quanyuan Feng Wensong Yu Cong Zheng 《International Journal of Circuit Theory and Applications》2013,41(5):514-534
The AC–DC power supply for LED lighting application requires a long lifetime while maintaining high‐efficiency, high power factor and low cost. However, a typical design uses electrolytic capacitor as storage capacitor, which is not only bulky but also with short life span, thus hampering performance improvement of the entire LED lighting system. In this article, a SEPIC‐derived power factor correction topology is proposed as the first stage for driving multiple lighting LED lamps. Along with a relatively large voltage ripple allowable in a two‐stage design, the proposal of LED lamp driver is able to eliminate the electrolytic capacitor while maintaining high power factor and high efficiency. To further increase the efficiency of LED driver, we introduced and used the twin‐bus buck converter as the second‐stage current regulator with Pulse Width Modulation (PWM) dimming function. The basic operating principle and the deign consideration are discussed in detail. A 50‐W prototype has been built and tested to verify the proposal. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
12.
13.
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
14.
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
15.
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
16.
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
17.
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
18.
基于Flyback的单级LED驱动电路的隔离变压器漏电感严重影响了驱动电路的工作效率,同时由于电解电容的存在,缩短了LED驱动电路的寿命。研究了一种带漏电感能量回馈通路的Buck-Boost+Flyback单级PFC驱动电路,利用一个二极管作为变压器漏电感能量回馈通路,消除开关管上的电压尖峰。建立了一定输出功率条件下中间级电容两端上限电压与电容值之间的函数关系,根据关系曲线选取合理的瓷片电容取代电解电容。研制一台输入130~260 V,输出为33 V/150 mA的实验样机验证了理论的正确性。 相似文献