DualBoostPFC电路拓扑的研究

传统的BoostPFC电路的整流桥损耗是通信开关电源的主要损耗之一。无整流桥的拓扑更具有效率优势。由于无桥BoostPFC省略了整流桥模块,效率显著的提高。文中分析了一种高效率的DualBoostPFC的大功率应用,通过实验证明了DualBoostPFC电路效率比传统的BoostPFC提高1个百分点,还介绍了电阻采样控制电路的使用和如何降低EMI干扰。     

无直流电压传感器的单相APFC变换器

文章对一种只检测交流输入电压而不需要检测输出直流电压的简化单相PFC变换器进行了理论分析和研究。在构建控制电路时,不需要常规PFC变换器中的输出电压传感器和输入电流传感器。PFC变换器的主电路为整流电路的直流侧接一级Boost电路。在控制电路中,使用电感L、等效负载电阻Rd等电路参数产生正弦电流波形基准,输出电压直接由控制量Kd(=Ed/Ea)来调节。通过控制,可以得到恒定的直流输出电压和与交流输入电压同相位的正弦电流波形。仿真结果证明了该变换器的可行性。     

基于BOOSt结构下不连续导电模式的PFC电路

采用现代高频功率变换技术的有源功率因数校正（Power Factor Corrector,PFC)技术是解决高频开关变换器谐波污染的有效手段。与传统的PFC电路相比，有源PFC电路的输入电流接近正弦波且与输与电压同相位，能有效抑制电流波形畸变和谐波，因此避免了对同一电网设施的干扰。在PFC电路中，Boost变换器是研究和应用得最多的一种变换器。本文着重分析了Boost电路在不连续导电模式状态下，PFC电路的临界条件，对实际电路结构的设计有很好的指导意义。     

通信电源发展综述

本简要介绍通信用整流器发展过程、器件发展对电路的影响、当前电路方案、移相桥的改进、三电平变换器、三相单管及三管功率因数校正、单级整流器等。     

Design and analysis of a novel zero-voltage-transition interleaved boost converter for renewable power applications

High-efficiency stepping up operation is an important feature of the converters used in renewable power applications due to the low voltage level of photo-voltaic arrays and fuel cells. Decreasing the switching losses of the converters is an effective solution for increasing the converter efficiency, especially in high-power applications. This article presents a novel zero-voltage-transition (ZVT) interleaved dc–dc boost converter that can be used in renewable power sources to reduce switching losses. The auxiliary circuit used in the proposed converter is composed of only one auxiliary switch and a minimum number of passive components without an important increase in the cost and complexity. The main advantage of the proposed converter is that it not only provides ZVT in the boost switches but also provides soft switching in the auxiliary switch. Another advantage of the proposed topology is that the semiconductor devices used in the converter do not have any additional voltage or current stresses. Also, it has a simple structure, low cost and ease of control. In this article, a detailed steady-state analysis of the proposed converter is presented. The theoretical analysis is verified via simulation and experimental studies which are in very good agreement.     

Efficiency investigation of dc–dc converter with passively damped input filter circuit

Passive damping of input filters in dc–dc converter applications has suffered enormous criticism presumably due to high conduction losses in the damping resistors. However, an accurate quantitative assessment of their adverse impact on efficiency is lacking. Similarly, not enough attention has been paid to the severity and extent to which they can effectively deteriorate a converter-efficiency under varying operating conditions. In order to quantify these losses we have performed a generalised power-loss analysis that helps in predicting this harmful effect of damping resistors on overall filter-converter system efficiency. A practical damping approach using a shunt R–C network, which is most commonly suggested in dc–dc converter applications, is investigated theoretically as well as experimentally. Results show that converter efficiency is susceptible to severe degradation, especially at high loads as well as at smaller damping resistor values. Furthermore, it is shown that these losses are considerably higher in buck-type converters than in boost-type converters. Authors emphasise that considering this negative impact on power economy is of crucial importance while optimising such a damping network.     

Boost converter with adaptive reference tracking control for dimmable white LED drivers

An LED driver consisting of dimmable current regulators and a boost converter with adaptive reference tracking control (ARTC) is proposed. The ARTC is realized with only one integrator and one subtractor to detect the voltage variation among the current regulators and then to generate an adaptive reference tracking voltage. Based on the reference tracking voltage, the driving voltage of the boost converter is dynamically adjusted, so as to not only maintain a minimum voltage on the current regulator but also keep the required LED-string current. A prototype control circuit including ARTC and PWM control fabricated with TSMC 0.35-μm 2P4M CMOS process validates the proposed technique. The measurement results show that the driving voltage of the boost converter is automatically regulated to compensate for the voltage alteration on the current regulators. Furthermore, the overall efficiency of the LED driver with ARTC is 6.1% better than that of the LED driver without ARTC.     

一种适用于生物医学信号采集的高线性度VGA

传统VGA线性度较低,不适用于生物医学应用.文章分析了基于可编程跨导器的传统结构,得出环路增益和失真的关系,并基于此采用增益提升技术提高环路增益,设计了一种新型的基于可编程跨导器的VGA,提高了 VGA的线性度.仿真结果表明,在1.2 V电源电压下,电路消耗电流为10 μA,在0～30 mV的输入信号幅度范围内,VGA...     

逆变电源的功率因数校正

分析了常用的无源和有源功率因数校正原理和方法，提出了用逆变电源负载端并联单相全桥整流器来实现功率因数校正的方法。功率因数校正器采用频率固定的PI控制，实现了在各种非线性负载下降低电流谐波含量，提高功率因数的目的。     

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。     

一种新的应用于开关电容DC/DC转换器的补偿电路

采用Chartered 0.35μm CMOS工艺,设计实现了输入电压范围2.7～5.5 V,负载电流高达200mA的降压式开关电容型DC/DC转换器.为了在整个输入电压和负载电流范围内稳定输出电压,并且提高输出电压精确度,在对开关电容转换器环路建模分析后,提出了一个新的应用于开关电容DC/DC转换器的频率补偿电路.该...     

Single-stage three-phase boost power factor correction circuit for AC–DC converter

This article presents a single-stage three-phase power factor correction (PFC) circuit for AC-to-DC converter using a single-switch boost regulator, leading to improve the input power factor (PF), reducing the input current harmonics and decreasing the number of required active switches. A novel PFC control strategy which is characterised as a simple and low-cost control circuit was adopted, for achieving a good dynamic performance, unity input PF, and minimising the harmonic contents of the input current, at which it can be applied to low/medium power converters. A detailed analytical, simulation and experimental studies were therefore conducted. The effectiveness of the proposed controller algorithm is validated by the simulation results, which were carried out using MATLAB/SIMULINK environment. The proposed system is built and tested in the laboratory using DSP-DS1104 digital control board for an inductive load. The results revealed that the total harmonic distortion in the supply current was very low. Finally, a good agreement between simulation and experimental results was achieved.     

嵌入式开关电容DC-DC变换器的新颖控制技术

提出了一种针对单片集成开关电容DC-DC变换器进行优化的设计方案.阐述了开关电容DC-DC变换器电路的拓扑结构及其基本工作原理,给出了单片集成开关电容DC-DC变换器的等效电阻控制方法.考虑到集成工艺的兼容性问题,在电路设计时,用n沟MOSFET替代二极管;为了改善变换器的输出特性,在标准2μm p阱双层多晶硅单层金属CMOS工艺中增加了一次MOSFET阈值电压的调整步骤,实现了升压开关电容DC-DC变换器的单片集成.芯片面积为0.4mm2,测试结果显示,在变换器输入电压为3V,输出电压为5V,电路开关频率为9.8MHz时,输出功率为0.63mW,效率达到68%.     

High-accuracy current sensing circuit with current compensation technique for buck–boost converter

A novel on-chip current sensing circuit with current compensation technique suitable for buck–boost converter is presented in this article. The proposed technique can sense the full-range inductor current with high accuracy and high speed. It is mainly based on matched current mirror and does not require a large proportion of aspect ratio between the powerFET and the senseFET, thus it reduces the complexity of circuit design and the layout mismatch issue without decreasing the power efficiency. The circuit is fabricated with TSMC 0.25 µm 2P5M mixed-signal process. Simulation results show that the buck-boost converter can be operated at 200 kHz to 4 MHz switching frequency with an input voltage from 2.8 to 4.7 V. The output voltage is 3.6 V, and the maximum accuracy for both high and low side sensing current reaches 99% within the load current ranging from 200 to 600 mA.     

Multiple output zero-current switching switched-capacitor bidirectional dc–dc converter

The proposed circuit is a multiple output quasi-resonant (QR) zero-current switching (ZCS) switched-capacitor (SC) converter with a bidirectional power flow control conversion scheme. The principles of the proposed multiple output QR ZCS SC bidirectional dc–dc converter are described using a detailed circuit model for analysis. Simulation and experimental results are carried out to verify the validity and the soft switching performance of the proposed converter. The maximum efficiency achievable is about 94 and 92% for the forward and reverse power flow control schemes, respectively. The output voltage can be regulated by changing the switching frequency for the designed compensated closed-loop controller.     

一种星载高效率电源的样机研制

针对星载合成孔径雷达电源高效率抗辐射的需求,对适用于星载领域的各种电源拓朴结构进行了对比分析,提出一种同步整流正激变换器拓扑方案。该方案采用单管栅极电荷保持驱动拓扑,解决了变压器死区时间续流管驱动问题,并对电路原理以及抗辐射加固方法进行详细说明,给出电路组成、关键器件和参数计算方法。根据所提方案制作了一台输入50 V～70 V、输出5 V/6 A的样机。实验结果表明：该电源具有高效率和抗辐射的特点,验证了技术方案的准确性,可以满足星载电源的需求。     

H桥级联型PWM整流器的原理与控制算法的研究

级联型H桥整流器随着级联H桥的增多,总电压被开关管分压,降低了每个开关管上的耐压要求,同时该拓扑可以实现能量双向流动,对功率因数进行校正,因此适用于无输入变压器的高压大容量场合。研究了级联型H桥的工作原理,针对直流母线电压不平衡问题,研究了一种基于比例-积分（PI）调节器的控制算法,保证空载和满载条件下都能够实现电压平衡控制。搭建三模块级联型H桥整流器的实验样机,实验结果表明了控制算法的有效性。     

嵌入式开关电容DC-DC变换器的新颖控制技术

提出了一种针对单片集成开关电容DC-DC变换器进行优化的设计方案.阐述了开关电容DC-DC变换器电路的拓扑结构及其基本工作原理,给出了单片集成开关电容DC-DC变换器的等效电阻控制方法.考虑到集成工艺的兼容性问题,在电路设计时,用n沟MOSFET替代二极管;为了改善变换器的输出特性,在标准2μm p阱双层多晶硅单层金属CMOS工艺中增加了一次MOSFET阈值电压的调整步骤,实现了升压开关电容DC-DC变换器的单片集成.芯片面积为0.4mm2,测试结果显示,在变换器输入电压为3V,输出电压为5V,电路开关频率为9.8MHz时,输出功率为0.63mW,效率达到68%.     

高功率密度LED驱动电源的设计

我国目前的照明主要以低效率的照明为主,LED由于其具有高效、节能、环保、可靠、长寿命等优点,正逐渐进入照明领域,对缓解目前环境恶化和能源短缺有重要意义.LED的性能与驱动电源性能和使用环境密切相关,需要开发出高效可靠的LED专用驱动电源与之配套.当前LED驱动电源存在功率密度、功率因数和效率较低等问题,因此开展高功率密度LED驱动电源的研究意义深远.