交错并联PFC的工作原理-世纪电源网.doc

常州工学院毕业设计论文 常州工学院毕业设计论文 PAGE 44 PAGE 43 常州工学院毕业设计论文 摘 要 功率因数校准技术作为改善电能质量的有效手段之一，在电力电子装置中得到了广泛的应用。怎样提高单相PFC电源的功率级和效率，减小PFC电源的体积成为了目前的研究热点.。单相PFC电路应用于大功率场合，需要应用大容量的开关管，而现有的MOSFET难以满足要求，采用交错并联技术就可以通过并联模块分流降低开关管的容量要求。同时由于并联的各变换器是交错运行，可以提升等效开关频率，减小输入电流纹波和输出电容纹波电流的有效值。本文选取了交错并联 Boost PFC电源作为研究目标。 本文针对大功率场合，研究了一种基于平均电流模式控制的交错并联Boost PFC变换器，选用UC3854作为控制IC。分析了在电感电流连续模式下交错并联Boost PFC电路的工作原理。利用状态空间法建立了平均电流模式交错并联Boost PFC小信号模型。在推导了平均电流闭环控制传递函数的基础上详细分析了闭环控制器的参数选取。最后通过Psim仿真软件对交错并联Boost PFC电路进行了仿真分析。试验结果表明, 验证了该控制电路能够准确控制主从开关的导通时刻，交错并联Boost PFC电路具有良好的功率因数校正效果。 关键词：功率因数校正；交错并联；平均电流模式；UC3854；Psim仿真 Abstract Power Factor Correction technology as an effective method to improve the quality of power has been extensive used in power electronic equipment. To enhance the power level of Single-phase PFC circuit and to minish the volume of the converter have been widely researched recently. While working in a high power level need a large -capacity switch tube. A new interleaved Boost PFC converter has been choosen to reduce the capacity of the switch tube requirements. Interleaved application realizes AC/DC convension through multiple converters, Which can increase switching frequency , reduce the ripple of input current and output capacitor. This paper selects interleaved Boost PFC as the research target. This paper mainly studies interleaved Boost PFC converters operating in average current mode for high power. And choose UC3854 as control IC. Analyzed the working principle of interleaved Boost PFC operating in continue current mode. Derived the small signal model of the interleaving Boost PFC circuit in average current mode by State-Space Average Method. On average current closed-loop control is derived based on the transfer function of detailed analysis of the closed-loop controller parameter selection. In the end, by Psim simulations on the whole circuit are performed to the theory analysis, and the results show that high power factor and low noise can be achieved by the new inter