共查询到19条相似文献,搜索用时 62 毫秒
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单级隔式PFC变换器是目前在小功率开关电源领域的一个研究热点。本首先介绍了单级隔离式PFC变换器的基本原理,分类以及特点,并在此基础上进一步探讨了控制方案。 相似文献
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结合开关电源发展的现状,分析和研究了高频和大功率情况下的开关电源实现方案,并对20 kHz/3 kW开关电源的主电路和控制电路进行了理论设计和参数估算.PSPICE软件仿真分析,表明该系统设计可行,性能指标基本满足设计要求. 相似文献
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针对Buck电路输入电流不连续而限制了Buck型功率因数校正技术的应用和发展问题,并考虑多电平拓扑结构的优势,提出了一种新型的三电平Buck型功率因数校正器拓扑结构.该拓扑结构基于输入、输出共地的Buck三电平变换器,在此变换器基础上并联增加了由功率开关、补偿电感和电容构成的补偿环节.新拓扑结构有效地解决了Buck电路输入电流不连续问题.实现了单位功率因数.且开关器件承受电压应力降低一半.控制策略基于单周控制技术,控制电路简单可靠,响应速度快,精确度高.对所提出的新型拓扑结构及其工作模态和控制实现进行了详细的分析,并给出了仿真和实验结果.结果表明校正后功率因数在0.99~1.0之间,验证了所提出的拓扑结构的正确性和有效性. 相似文献
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新型单级隔离型软开关功率因数变换器 总被引:1,自引:1,他引:1
提出一种兼具软开关和箝位的新型单级隔离型功率因数校正(power factor correction, PFC)变换器拓扑。该变换器能满足电气隔离的应用要求,提升单级隔离型PFC的功率等级。与传统单级结构相比,新拓扑输入电流校正效果明显,功率因数接近1。比较理想地解决了限制单级PFC功率等级的变压器漏感和直流母线电容应力问题。箝位电容被充分利用简化了零电压过渡(zero voltage transition,ZVT)技术在隔离型变换器中的应用,既改善了半导体器件的开关环境、优化系统电磁兼容,又提高了变换效率。实验制作一台87 kHz,1 kW的样机。实验结果表明,这种变换器的效率基本能够达到93%(半载以上),功率密度提高,适合于中大功率应用场合。 相似文献
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高功率因数48 V/50 A通信开关电源 总被引:1,自引:0,他引:1
通信业的迅速发展,要求通信一次电源具有更高的效率、更高的可靠性、更小的体积和重量 ,以及对电网产生尽可能小的谐波污染。此外,为利于集中监控及无人值守,要求电源具有 遥测、遥控、遥信接口。文中给出了一种具有高功率因数的开关电源的设计与实现。该电源 输入级采用单相升压型功率因数校正器,DC/DC变换采用双管双正激变换器,并采用8031单 片机控制的RS 485串行口作为监控接口。 相似文献
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基于新型功率因数校正器UCC28019,设计一款功率为72W,输出为36V的高功率因数开关电源。对其电路的工作原理和各元件参数进行详细分析,并给出该开关电源重要指标的测试结果。试验结果证明,该开关电源功率因数高,纹波小,输出电压稳定,性能良好。 相似文献
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设计了一台高功率因数直流开关电源.采用有源箝位技术,实现主电路的软开关;基于专用复合控制芯片,简化控制系统的设计.实验结果表明,所设计的电源,其性能指标达到要求. 相似文献
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基于SEPIC变换器的高功率因数LED照明电源设计 总被引:1,自引:0,他引:1
针对LED驱动电源功率因数低的问题,依据LED照明电源的特点,选择SEPIC电路作为主电路拓扑实现功率因数校正(PFC)和LED电流控制。传统的SEPIC电路用于功率因数校正时都工作在断续模式下,通过对SEPIC电路的分析,证明了临界连续模式下SEPIC电路也可以实现PFC,并推导出输入输出电压比和功率因数关系的公式,得出当输入输出电压比很小时,功率因数值很高。该电源用单级电路同时实现功率因数校正和LED电流控制,相对两级功率因数校正电路,所用器件少,损耗低,尺寸小,尤其适合空间狭小的照明电源电路。通过实验证明理论分析的正确性。 相似文献
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C. K. Tse 《International Journal of Circuit Theory and Applications》2003,31(2):157-198
This paper discusses the circuit theory aspects of power factor correction in switching converter circuits. The discussion begins with an examination of the requirement of power factor correction in dc/dc converters. Using the concept of zero‐order converter circuits, sufficient conditions for a dc/dc converter circuit to provide power factor correction are derived. The duality principle is applied to generate new converter circuits that can achieve power factor correction. The practical application of power factor correction is considered in conjunction with the requirement of tight output voltage regulation. Detailed study of the circuit configuration that can simultaneously provide power factor correction and output regulation is given. Based on a general three‐port model, the voltage regulator with power factor correction capability is studied in terms of the power flow between the input port, output port and energy storage port. A detailed consideration of the power flow among the three ports leads to the derivation of all possible minimal configurations that can achieve power factor correction and voltage regulation. The efficiencies of these minimal configurations are studied theoretically, leading to the concept of ‘reduced redundant power processing’ which provides important clue to efficiency improvement. Another issue addressed in this paper is the synthesis of practical circuits that can provide power factor correction and output regulation. In particular, four practical minimal configurations that achieve reduced redundant power processing are considered. A systematic synthesis procedure is derived for creating converter circuits that achieve power factor correction and output voltage regulation. The control issue is also investigated in depth, pinpointing the basic requirement on the number of control parameters needed and its relationship with the operating mode. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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MATLAB下利用BUCK-BOOST变换器实现通信电源功率因数校正的仿真分析 总被引:1,自引:0,他引:1
详细分析了用BUCK-BOOST实现电路功率因数校正的原理和变换过程,并给出了BUCK-BOOST电路的Matlab仿真分析的模型。通过对变换器工作在DCM模式下的电路仿真,验证了此方法的良好效果。 相似文献
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Abdelhalim Kessal Rahmani LazharJean-Paul Gaubert Mostefai Mohammed 《Electric Power Systems Research》2011,81(9):1825-1831
This paper presents an analysis and a modeling approach to obtain a small-signal model design and the digital implementation of a linear control technique for single-phase boost power factor correctors (PFC). Such converters present nonlinear characteristics and approximations of them are used to drive the models. The proposed circuit significantly improves the dynamic response of the converter to load steps without the need of a high crossover frequency of the voltage loop by adding low-pass filter. So, a low distortion of the input current is easily achieved. This controller has been verified via simulation in Simulink using a continuous time plant model and a discrete time controller. Real-time implementation is performed on an experimental test bench utilizing a rapid prototyping tool. The controller is experimentally confirmed for steady-state performance and transient response. 相似文献