光伏电池最大功率跟踪算法的优化设计

光伏电池输出功率受到光照强度、温度和负载等因素的影响而变化,有必要对光伏电池进行最大功率跟踪。文中提出了新的扰动观察MPPT方法,该方法通过控制Boost变换器的占空比来实现最大功率的控制。该方法具有跟踪效率高、跟踪速度快、跟踪控制简单的优点,仿真验证了该方法的有效性。     

一种适用于Boost电路的自适应斜坡补偿电路

设计了一种适用于峰值电流模式Boost电路的自适应斜坡补偿电路。电路通过动态检测Boost电路的输入输出电压,产生随Boost电路开关控制信号占空比变化的斜坡电压,实现补偿斜坡斜率的最优化。由于本设计采用了高精度减法器,斜坡补偿精度得到提高,在消除次谐波振荡、提升Boost电路稳定性的同时,将补偿对Boost电路的负面影响最小化,保证了Boost电路的带载能力和动态响应速度。采用SMIC 0.18μm CMOS工艺完成电路设计和版图绘制,并进行了后仿验证,结果显示,工作电压为3.3 V时,在不同工作条件下,随着开关占空比的变化,补偿斜率可以实现自适应调整,与理论最佳补偿斜率的误差范围仅为1.39%～2.33%。     

宽负载应用的自适应关断时间Boost电路

设计了一种新型自适应关断时间(AFT)模式Boost电路。不同于传统的采样输入/输出电压的自适应电路,该AFT模式Boost电路直接采用真实的占空比信息,设置了自适应比较点,解决了开关频率受负载电流影响的问题。基于0.5 μm CMOS工艺对电路进行仿真验证。结果表明,当输入电压在2.4~4.2 V、负载电流在0.3~1.2 A范围内变化时,该AFT模式Boost电路的工作频率稳定在967~972 kHz之间,频率变化范围仅为传统自适应电路的14.3%。     

单周期控制无桥Boost PFC电路分析和仿真

传统有源功率因数校正电路中导通器件多，通态损耗大，不适于中大功率场合应用。新颖的单相功率因数校正电路——无桥Boost拓扑，其结构简单，效率高。文中基于无桥Boost电路，提出一种单周期控制方法，它不需要检测输入电压信号且不需使用乘法器就能实现功率因数校正。单周期控制电路简单可靠，又降低了成本。文中分析了无桥Boost电路及单周期控制的工作原理，并导出了控制系统的稳定性条件。     

基于模糊理论的光伏发电最大功率点跟踪控制策略研究

介绍了光伏电池的特性,最大功率点跟踪原理和Boost变换电路,提出了一种基于模糊逻辑控制的最大功率点控制策略,即将光伏电池和Boost电路作为一个整体,通过检测负载功率的变化,来调整控制开关占空比,简化了系统。仿真结果表明,当外部环境发生变化的时候,系统能够迅速跟踪此变化,使系统始终工作在最大功率点附近,并具有较好的稳定性。     

基于MSP430的LED驱动搭建

本设计采用TI公司超低功耗单片机MSP430F5529A作为系统主控芯片,以TI公司Boost型升压电源芯片TPS61040为主要电源芯片。本设计利用MSP430内部的PWM发生器产生PWM信号,将其接入的电源芯片的使能端,通过控制该PWM信号的占空比来控制一定周期内电源电路工作的时间,使LED负载两端的平均电压按预定规律变化,进而转化为负载电流的变化。通过大量测试得到各工作电流下对应的PWM信号占空比信息,存储到单片机中供程序调用以实现对电流的稳定控制。大量实验数据证明,本设计工作稳定,设计简单,达到了预期效果。     

无桥Boost PFC技术的研究

与传统Boost PFC电路相比,无桥Boost PFC电路能提高整机效率,特别适用于中大功率电路中.实验基于无桥Boost PFC拓扑,控制电路分别采用“平均电流控制“技术的芯片L4981和“单周期控制“技术的芯片IR1150,研制出一台1500W的实验样机,并对两种控制电路进行了详细的对比分析.实验结果证明两种控制方法均能达到较好的功率因数校正效果,功率因数大于0.97,THD值小于10%.     

应用于UPS的3 kW Boost电路研究

提出了基于UC3842的Boost(升压)电路控制策略,运用开关函数法建立了Boost功率电路的高频数学模型,进而给出了状态空间平均模型,基于这一模型,从控制理论的角度分析了Boost电路的能控、能观测性。文中给出了占空比的输入到输出的小信号传递函数,为设计校正补偿网络提供了理论依据。这一电路可应用于中小型UPS(不间断电源)中,给蓄电池升压,为UPS中的逆变器提供输入电压,可以满足掉电时UPS的动态性能。最后给出的仿真和实验结果,证明了文中分析的正确性和UC3842控制的实用性。     

高升压比交错并联Boost电路的分析

文章分析了传统Boost电路在实际应用中存在的问题,提出了一种改进型的交错并联Boost电路。在电感电流连续模式下,根据占空比大于或小于0.5的情况,详细分析电路的工作过程,推导了稳态情况下输出输入电压关系式,最后通过仿真验证了理论分析的正确性。     

基于滑模变结构的交错并联Boost电路均流控制研究

Boost电路常常被用于新能源行业中的升压电路,如光伏发电系统、功率因数校正电路等。交错并联的Boost电路更是因为其散热均匀、器件的电流应力小、体积更小等优势而替代一路Boost被广泛应用。在三路交错并联Boost电路的基础上,采用一个开关周期内三路IGBT的开关信号相差120°的模式实现均流控制。同时,为了对输出电压以及电感电流进行良好控制,提出采用电压外环以及滑模变结构的电流内环控制方法。仿真和实验波形验证了所提方法的有效性。     

CMOS single-stage input-powered bridge rectifier with boost switch and duty cycle control

This paper presents a single-stage input-powered bridge rectifier with boost switch for wireless-powered devices such as biomedical implants and wireless sensor nodes. Realised using CMOS process technology, it employs a duty cycle switch control to achieve high output voltage using boost technique, leading to a high output power conversion. It has only six external connections with the boost inductance. The input frequency of the bridge rectifier is set at 50 Hz, while the switching frequency is 100 kHz. The proposed circuit is fabricated on a single 0.18-micron CMOS die with a space area of 0.024 mm². The simulated and measured results show good agreement.     

Single-stage single-switch isolated PFC regulator with unity powerfactor, fast transient response, and low-voltage stress

In this paper, a simple control method is presented for a single-stage single-switch isolated power-factor-correction (PFC) regulator that can simultaneously achieve unity power factor and fast output voltage regulation while keeping the voltage stress of the storage capacitor low. The converter topology comprises essentially a cascade combination of a discontinuous-mode boost converter and a continuous-mode forward converter. The proposed control utilizes variation of both duty cycle and frequency. The role of varying the duty cycle is mainly to regulate the output voltage. Changing the frequency, moreover, can achieve unity power factor as well as low-voltage stress. Basically, the switching frequency is controlled such that it has a time periodic component superposed on top of a static value. While the time periodic component removes the harmonic contents of the input current, the static value is adjusted according to the load condition so as to maintain a sufficiently low-voltage stress across the storage capacitor. The theory is first presented which shows the possibility of meeting all three requirements using a combined duty cycle and frequency control. An experimental prototype circuit is presented to verify the controller's functions     

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。     

用于LCD测试系统的程控驱动器设计

为了制作一款用于LCD测试系统的程控驱动器,采用基于嵌入式系统ARM7实现程序控制,内建DC/DC升压电路和DC/AC转换电路,以提供直流电源和产生驱动脉冲信号,电源内建/外接可选,其信号输出端按一定时序产生特定的连续脉冲, 供给LCD 屏的行列电极作驱动源, 从而使被选行与被选列交叉位置上的液晶像素或笔段在电场作用下呈现显示状态（遮光或透光） 。该系统输出的工作电压峰值、频率、占空比均可调,是一款低功耗、低输出阻抗的LCD程控驱动器。     

基于FPGA的光弹调制器用高压驱动电路设计

为满足光弹调制器对高电压、高稳定和精确易控制的驱动电压需求,设计了一种基于FPGA控制、全桥结构LC谐振升压的高压驱动电路。该电路与传统的光弹调制器驱动控制电路相比,大幅降低了直流电源的电压输入要求,通过DDS调节方波频率来控制光弹调制器工作频率,调节方波占空比来控制输出电压。该电路应用于光弹调制器实验,结果表明在光弹调制器的谐振频率下,外部直流电压为5 V时,方波占空比范围为0~50%,对应电压峰-峰值可调节范围为0~840 V。电路具有稳定可靠、操控方便、带负载能力较强等优点,能够实现光弹调制器驱动电压实时精确的控制。     

Switching-Frequency Control for Regulated Discontinuous-Conduction-Mode Boost Rectifiers

A novel switching-frequency control method for regulated one-switch boost rectifiers operating at the boundary of discontinuous and continuous conduction modes is presented in this paper. To obtain a source current with the least amount of low-order harmonics, the duty cycle within a switching period is proportional to the ratio of the instantaneous value of the source voltage to the output voltage. According to the voltage gain analysis, the output voltage can be regulated by adjusting the switching frequency. Small-signal modeling is performed to facilitate the design process. The proposed control scheme features advantages such as higher input power factor and higher regulated output voltage compared to the traditional discontinuous conduction control with a fixed switching frequency and a constant duty cycle. Any well-developed commercial pulsewidth-modulation control integrated circuit can be adopted with only a minor modification. Experimental results show good conformation with the theoretical analysis     

一种恒压输出的DC-DC升压电路设计

针对DC-DC升压器存在效率低,纹波电压较大,输出电压不稳定等问题,文中开发和设计了一种具有恒定输出电压的DC-DC升压转换器的方法。通过升压电路和电压反馈技术,将波动的输入电压变成恒定的直流电压输出。该设计通过将转换器的输出电压与参考电压相比较,两者的差值会产生一个PWM信号控制升压器的通断时间,从而达到恒定电压输出。仿真结果显示,该实验电路能在频率为20 kHz的连续导通模式中工作,产生24 V的恒定输出电压,输出功率为100 W。     

Interleaved soft switching resonant converter with a small input ripple current

ABSTRACT

An interleaved frequency control soft switching converter is studied for solar power or fuel cell power applications. The proposed circuit topology contains two parallel current-fed circuit cells with interleaved pulse-width modulation operation. Thus, the ripple currents at input and output terminals are decreased. In each circuit cell, the proposed current-fed dc-dc converter includes boost circuit and resonant circuit to achieve current ripple-free on low voltage side and less switching losses on active devices. The boost circuit and the resonant circuit have same active devices to decrease power switches. Due to the resonant behaviour, the reverse recovery current loss on secondary diodes is removed. The voltage doubler circuit topology is accomplished on secondary-side to reduce diode counts and conduction loss. The performance and effectiveness of the developed interleaved PWM current-fed converter are verified and confirmed by experiments.     

Limits in boost power factor corrector operating in border-line mode

The single-phase boost power factor correctors may operate in the so called border-line mode, which is distinguished by variable switching frequency. If some constraints are imposed on variability of this frequency some limits to output voltage and power of the circuit appear at once. The paper shows the origin of them and presents formulas and graphs helpful in a proper choice of circuit parameters in order to keep the switching frequency within a predefined range, also under the changes of input line voltage and of the load resistance.     

CMOS反相器高功率微波扰乱效应分析

通过对CMOS数字电路器件及RF脉冲扰乱效应的模拟分析,比较了注入不同频率与功率的RF扰乱脉冲时对CMOS反相器输出逻辑电平扰乱甚至翻转的效应过程。