【作者】 孙洪雷；

【导师】 邬伟扬； 金海龙；

【作者基本信息】 燕山大学 ， 电力电子与电力传动， 2006， 硕士

【摘要】 电子仪器及电力电子装置中大量的谐波电流极易对周围设备产生电磁干扰,同时也造成了对电网的谐波污染。对于数量多而且分散的中小功率电源系统,最有效的方法就是在电源内部采用功率因数校正(PFC)和谐波抑制措施,从根本上消除谐波源。近年来功率因数校正技术受到了国内外电源界的高度重视,其中功率因数校正技术研究的一个热点问题就是新拓扑的提出。论文首先阐述了功率因数校正技术的研究现状,对两级PFC变换器和单级PFC变换器的拓扑结构进行了比较,归纳了各自的优缺点。在此基础上,本文从高频谐振环节实现功率因数校正的工作原理分析入手,推导了功率因数的表达式,证明了高频谐振环节实现单位功率因数的可行性,并把高频谐振环节与单管反激式变换器相结合,提出了一种新型的单级隔离式PFC变换器拓扑,详细分析了主电路各开关状态的工作过程,进行了主要参数的计算和磁性元件的设计。该电路利用谐振电感代替Boost型PFC变换器的输入储能电感,谐振电感电流工作在断续导电模式(DCM),解决了Boost型PFC变换器中存在开关管关断损耗过大的问题,并且可以同时实现功率因数校正和输出电压调节。控制电路采用MSP430超低功耗单片机作为主控芯片,实现了该变换器的全数字化控制。最后,针对所提出的新型单级隔离式功率因数校正(PFC)变换器的拓扑方案进行了仿真和实验研究,设计了一台120 W开关电源的实验样机。该样机在实验中测得输入电流总谐波畸变率(THD)为4.26%,功率因数为0.998,达到了预期的设计效果。更多还原

【Abstract】 A large number of harmonic current from electronic machines and electricpower devices generate emission of noise interference to peripheral deviceseasily, at the same time, electric network suffers harmonic pollution. Fornumerous and decentralized power supplies, the most effective method tosuppress harmonic source ultimately is Power Factor Correction (PFC).Recently, internal and overseas power supply fields put highly premium onPower Factor Correction technique. Especially, a new topology proposed do isa hot spot of Power Factor Correction technique.Firstly, the paper summarizes the current research situation of correctiontechnology for active power factor. Topologies of two-stage PFC convertersand single-stage PFC converters are compared with. Furthermore, the virtuesand defects of them are generalized.In the second place, at the beginning of operating principle analysis byhigh frequency resonance link leading-in Correction, the expression wasdeduced, and feasibility of realizing unit Power Factor was justified. The paperproposed the topology of novel single-stage isolated PFC converter andanalyzed the work principle of the circuit. Consequently, primary parametersand magnetic elements were designed. Resonance inductor instead of theinductor in two-stage Boost PFC converter works in Discontinuous ConductionMode (DCM). The converter that the paper proposed solves the problem ofexcessive dissipation of the switch in two-stage Boost PFC converter. PowerFactor is corrected and output voltage is regulated at the same time. MSP430microcontroller that is super low power acts as a master controller in thecontrol system, and digital control of this converter is realized.At last, the research of simulation and experiment is implemented on theproposed topology and control methods. A 120 W prototype was designed. Themeasured input current THD is 4.26%. Power Factor attains 0.998. Theprototype realizes the expectation.更多还原