单相两级有源功率因数校正变换器的研究

文中对两级有源功率因数校正变换器进行研究,设计了一台510W两级式开关电源。该电源前级采用平均电流控制的Boost型PFC电路,实现功率因数校正;后级采用不对称半桥型DC／DC变换器,实现开关管的零电压开关。控制电路采用PFC／PWM复合控制芯片ML4824,缩小电源体积。通过实验证实该开关电源具有高功率因数与高效率的特点。     

一种等离子显示系统专用电源

设计了一个用于多屏拼接等离子显示系统的专用电源。该电源采用两级变换,前级AC/DC变换采用Boost型有源功率因数校正电路,后级变换器对于不同的回路根据功率的大小分别采用全桥变换器和单端反激变换器。对传统Boost型功率因数校正电路提出了一点改进,有效抑制了传统Boost型功率因数校正电路中大功率时开关管开通时二极管上瞬时大电流。后级变换器中主回路采用一种次级无源箝位ZVZCS全桥变换器,适宜大功率的输出且有效降低了开关损耗。     

新型雷达固态收发模块电源的设计

为了达到雷达固态收发模块对电源高效变换的要求,提出了一种基于谐振技术的新型电源变换器设计方案。电源采用两级功率变换,前级为隔离型变换器,完成输入功率因数校正(PFC),起到降压、隔离及初步稳压的作用。后级为多路非隔离降压型(BUCK)谐振变换器,实现输出电压的进一步的调节。后级的BUCK谐振变换器利用电感和电容谐振实现了功率管的零电流(ZCS)和零电压(ZVS) 开关。在高频化的同时降低了开关损耗,同时电路工作原理简单,易于实现和控制。设计方案对该电路工作原理和特性进行了详细分析,并给出固态收发模块电源主要参数设计及电源工作的部分波形。     

带有PFC功能的适配器设计

随着开关器件在各种电能变换器中的广泛应用,虽然提高了变换器的转换效率,但是带来了谐波污染和功率因数降低等问题。为了消除谐波污染并改善功率因数,设计一款隔离型电源适配器,以TI公司的电源芯片UCC28019为核心,具有功率因数校正(Power Factor Correction,PFC)、精密恒压/恒流输出功能。通过对适配器各分单元的原理介绍,对主电路中电感和变压器进行参数计算,对电路进行仿真验证,证明了该方法的可行性。     

基于RC滤波融合二次方运算的Boost-PFC变换器研究

为减少开关变换器电流谐波对电网的污染,降低变换器输出电压超调,提高变换器的稳定性,以单相Boost型拓扑结构功率因数校正（PFC）变换器为研究对象,对变换器原理及其工作模态等效电路进行分析。基于平均电流控制方式,提出一种RC滤波融合二次方运算的输入电压采样方案,在输入电压采样支路增加一个RC滤波电路和一个二次方运算电路,更精确地对输入电压进行采样,从而减少变换器电流谐波、提高变换器稳定性。在Matlab/Simulink软件中搭建仿真电路,同时设计了实验样机进行验证。结果表明,与传统功率因数校正电路相比,该方案有效减少了变换器电流谐波,抑制了变换器输出电压尖峰,同时提高了变换器的输出稳定性。     

电子元件、组件

TM42 2005020574 单级桥式P FC电路功率变压器偏磁的产生机理分析/贵洪奇,金祖 敏,王凤平(哈尔滨工业大学)刀哈尔滨工业大学学报,一2 004,36(9 )一1215一1219 提出一种单级全桥软开关功率因数校正电路,它采用移相控制方式,能 同时实现功率因数校正、软开关、输出电压调节和电气隔离.但由于电路 特殊的控制方式和所要实现的功率因数校正功能,该校正电路中的功率 变压器除存在普通全桥变换器产生偏磁的原因外,还存在产生偏磁的特 殊因素.该文在分析变换器的电路结构和工作原理之后,对偏磁的产生 机理进行了分析,指出了该变换器影响偏磁大小…     

一种基于三电平的单级PFC电路设计

通过在多电平变换技术和功率因数校正技术两者之间寻找一个应用的契合点,给出了一种零电压开关三电平单级功率因数校正电路拓扑的设计方法。该方法中的变换器由boost功率因数调节器和三电平谐振变换器组成。其中变换器控制方式由两个控制环路实现,输出电压通过控制直流变换器开关频率来进行调节;直流母线电压则通过控制boost调节器的占空比来调节。仿真分析表明,运用该拓扑的变换器的功率因数较高;并可在宽负载变化情况下提供可调节的输出电压以及一个稳定的直流母线电压。     

有源功率因数校正技术在开关电源中的应用研究

提高开关电源的功率因数已经成为国内电源厂商的当务之急。文中设计了一种采用功率因数校正专用芯片MC33262的宽电压输入范围、固定升压输出的150W的AC/DC变换器，详尽地分析和讨论了有源功率因数校正(APFC)控制技术原理、APFC硬件电路结构。实验结果表明文中所设计的带APFC的AC/DC变换器在宽广的输入电压范围(95～250V)下能够正常工作，各项性能指标均符合要求。     

高输入功率因数的三相无源AC-DC变换器

对于采用三相不控整流桥作为前级的变换器，自然条件下其输入电流波形系数不高，使得输入功率因数委低，降低了电源的利用率。为此需要采用功率因数提高技术，其中无源PFC是一类重要的功率因数校正技术，在某些场合非常具有应用价值。本文介绍了几种三相无源AC-DC变换器的高功率因数方案，如采用LC滤波器、移相电抗器，谐振电抗器，移相变压器，相间变压器，相间电抗器等，在进行简单的工作原理描述后，给出了部分方案的MATLAB/SIMULINK仿真结果。     

1100W开关电源前级功率因数校正技术的研究

功率因数校正技术作为雷达电源系统的一项关键技术应用到开关电源中 ,有利于电源技术指标的提高 ,对雷达供电系统的有效运行带来很大的益处 ,越来越成为电源行业研究的热点。介绍了功率因数校正技术的发展和特点 ,分析了平均电流型技术 ,给出了 110 0W开关电源前级的功率因数校正电路的设计方法和实验结果     

Magnetic-coupled high power factor converter with low line currentharmonic distortions for power factor correction and fast outputresponse

A new magnetic-coupled high power factor converter (MCHPFC) with a single switch/single stage is proposed. The proposed converter gives good power factor correction, low current harmonic distortions, and tight output voltage regulation. The prototype shows that the IEC555-2 requirements are met satisfactorily with nearly unity power factor. A proposed MCHPFC is particularly suited for low-power-level power supply applications     

Power factor correction converter using delay control

A low cost universal input voltage single-controller power factor correction converter for a 200 W power supply is proposed. It consists of the PFC part followed by a DC-DC converter as in a conventional two-stage scheme. However a single PWM controller is used as in a single-stage PFC scheme. The switch in the PFC part is synchronized with the switch in the DC-DC converter and has a fixed frequency. Employing an adaptive delay scheme, the PPC switch is controlled to limit the capacitor voltage within a desired range for optimum efficiency and to reduce input current harmonic distortion. The design procedures of the delay scheme, the feedback loop, and experimented results are presented to verify the performance     

智能高频开关电源系统中整流模块的功能设计

以智能高频开关电源系统中的整流模块为研究对象,采用无源PFC和DC/DC变换器的原理,对模块的整流原理进行设计和改善,经过对整流模块的硬件、电路的设计与调试表明：该整流模块可以有效地解决智能高频开关电源系统中整流问题,同时,还具有可靠性强、稳定性好且体积小、噪声低、节能高效、维护方便等优点,能够很好地满足现代智能高频开关电源系统的发展趋势要求。     

基于Sepic和Flyback混合拓扑的辅助电源设计

分析了Sepic和Flyback拓扑结构,根据DC/DC模块电源对辅助电源的需求,提出了Sepic和Flyback混合拓扑的辅助电源,能够输出多路不同幅值电压,并且可以实现各路输出电压之间的隔离。利用状态空间平均法建立了Sepic拓扑的小信号模型,设计了电压和电流双环控制的补偿器,并用Matlab仿真软件进行了分析。该辅助电源应用于一款非隔离的宽范围输入且输出可调的DC/DC模块电源,实现了三路互相隔离的12 V输出电压,一路非隔离的6 V输出电压,输出电压波形稳定,能够满足隔离悬浮供电,也能满足不同芯片对电压范围的要求。     

Buck–Boost-Type Unity Power Factor Rectifier With Extended Voltage Conversion Ratio

A buck-boost-type unity power factor rectifier is proposed in this paper. The main advantage of the proposed rectifier over the conventional buck-boost type is that it can perform input power factor correction (PFC) over a wider voltage conversion range. With a single switch, a fast well-regulated output voltage is achieved with a zero-current switch at turn-on. Moreover, the switch voltage stress is independent of converter load variation. The proposed converter is well suited for universal offline PFC applications for a low power range (<150 W ). The feasibility of the converter is confirmed with results obtained from a computer simulation and from an experimental prototype.     

基于LD7550B的反激变换器设计

单端反漱变换器是应用较广泛的一种拓扑形式,基于LD7550B的反激变换器具有许多优良的特点.变压器设计是开关电源设计的一个非常重要的组成部分,通过10W功率变换器的设计可以基本掌握LD7550B的用法,开关电源中PCB的设计对电源的性能至关重要,通过反激变换器的一些实测波形对于设计类似的开关电源有一定的指导作用.     

A digitally controlled switch mode power supply based on matrix converter

High power telecommunication power supply systems consist of a three-phase switch mode rectifier followed by a dc/dc converter to supply loads at -48 V dc. These rectifiers draw significant harmonic currents from the utility, resulting in poor input power factor with high total harmonic distortion (THD). In this paper, a digitally controlled three-phase switch mode power supply based on a matrix converter is proposed for telecommunication applications. In the proposed approach, the matrix converter directly converts the low frequency (50/60Hz, three-phase) input to a high frequency (10/20kHz, one-phase) ac output without a dc-link. The output of the matrix converter is then processed via a high frequency isolation transformer to produce -48V dc. Digital control of the system ensures that the output voltage is regulated and the input currents are of high quality under varying load conditions. Due to the absence of dc-link electrolytic capacitors, power density of the proposed rectifier is expected to be higher. Analysis, design example and experimental results are presented from a three-phase 208-V, 1.5-kW laboratory prototype converter.     

基于Sepic电路的工业照明设备节能电源设计

在照明领域,LED发光产品的应用正吸引着世人的目光,LED作为一种新型的绿色光源产品,必然是未来发展的趋势。 LED驱动电源作为LED照明的核心技术之一,功率因数及效率一直偏低,成为阻碍LED照明工程化应用推广的主要瓶颈。基于Sepic拓扑并带有功率因数校正的LED驱动电源不仅能有效地提高功率因数及效率,降低无功损耗,同时对于节能减耗、降低成本也有非常重要的意义。     

Integrated ZCS quasi-resonant power factor correction converterbased on flyback topology

An integrated zero current switching (ZCS) quasiresonant converter (QRC) for the power factor correction with a single switch is presented in this paper. The power factor correction can be achieved by the discontinuous conduction mode (DCM) operation of an input current. The proposed converter offers good power factor, low level line current harmonics, and tight output regulation. The design equations are suggested and a prototype converter has been designed based on these equations and experimentally investigated. The input current waveform of the prototype shows less than 15% of total harmonic distortion. Also, the efficiency and power factor of about 84% and 0.977, respectively, can be obtained under the rated condition     

A Single-Stage High-Power-Factor Electronic Ballast Based on Integrated Buck Flyback Converter to Supply Metal Halide Lamps

In this paper, a novel single-stage electronic ballast with a high power factor is presented. The ballast circuit is based on the integration of a buck converter to provide the power factor correction, and a flyback converter to control the lamp power and to supply the lamp with a low-frequency square-waveform current. Both converters work in discontinuous conduction mode, which simplifies the control. In spite of being an integrated topology, the circuit does not present additional stress of voltage or current in the main switch, which handles only the flyback or buck current, depending on the operation mode. To supply the lamp with a low-frequency square-wave current to avoid acoustic resonances, the flyback has two secondary windings that operate complementarily at a low frequency. The design procedure of the converters is also detailed. Experimental results from a 35-W metal halide lamp are presented, where the proposed ballast reached a power factor of 0.95, a total harmonic distortion of 30% (complying with IEC 61000-3-2), and an efficiency of 90%.