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buck电路对通信电路的影响

汽车电器 2024年第2期 75-76,79页

作者：佟刚深圳市瑞车品科技有限公司广东深圳518000

为解决buck电路对通信设备灵敏度的影响,文章先对buck电路原理进行分析,然后总结出buck电路产生干扰的原因并进行系统分析,最后得出解决该问题的方法为:拉长buck电路上升沿或下降沿时长;buck电路降低振铃频率。通过验证分析,文章给出的... 详细信息

为解决buck电路对通信设备灵敏度的影响,文章先对buck电路原理进行分析,然后总结出buck电路产生干扰的原因并进行系统分析,最后得出解决该问题的方法为:拉长buck电路上升沿或下降沿时长;buck电路降低振铃频率。通过验证分析,文章给出的实际电路5种解决方法,在应用设计中能明显改善通信电路的灵敏度问题。

关键词： buck EMI 寄生谐波

Antioxidant potential of pentoxifylline on spermatozoa of small ruminants

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Asian pacific Journal of Reproduction 2022年第3期11卷 138-145页

作者： Mazen Alomar Division of Animal Production Department of AgricultureAtomic Energy CommissionP.O.Box 6091DamascusSyria

Objective:To investigate antioxidant potential of pentoxifylline on spermatozoa of small ruminants including rams and bucks.Methods:The levels of hydrogen peroxide(H2O2)production in ram and buck spermatozoa incubated with 0(control),4 and 8 mM of pentoxifylline were measured after 45-min incubation.Then,the motility parameters of ram and buck spermatozoa incubated with 0(control),1 mM of H2O2,1 mM of H2O2 plus 4 mM of pentoxifylline,and 1 mM of H2O2 plus 8 mM of pentoxifylline were analysed.H2O2 was estimated using a fluorometric assay and spermatozoa motility characteristics were analyzed using computer aided sperm analyzer.Results:Pentoxifylline significantly decreased the levels of H2O2 produced from both ram and buck spermatozoa(Pbuck sperm samples,the rapid and static subpopulation motility parameters were the most affected categories by pentoxifylline addition compared to the medium and slow categories.Conclusions:Pentoxifylline possesses an antioxidant capacity proved by its ability of reducing H2O2 levels as well as by increasing motility values of stressed spermatozoa.Therefore,pentoxifylline could be recommended as antioxidant additive for spermatozoa of small ruminants under stress conditions.

关键词： Pentoxifylline Spermatozoa Ram buck Motiltiy Hydrogen peroxide H2O2 Antioxidants

采用开关电感的buck变换器CCM和DCM特性分析

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电工技术学报 2022年第16期37卷 4155-4168页

作者：祁静静吴学智王久和续文政刘京斗北京交通大学国家能源主动配电网技术研发中心北京100044 北京信息科技大学自动化学院北京100192

buck型DC-DC变换器采用开关电感单元后能拓宽电压变换范围且减小器件电流应力,但该文经推导发现,因电感的串并联切换会使等效电流分别为单电感电流的一倍和两倍,导致与负载电流的关系不确定,并使变换器变为非最小相位系统。该文以开关电... 详细信息

buck型DC-DC变换器采用开关电感单元后能拓宽电压变换范围且减小器件电流应力,但该文经推导发现,因电感的串并联切换会使等效电流分别为单电感电流的一倍和两倍,导致与负载电流的关系不确定,并使变换器变为非最小相位系统。该文以开关电感buck变换器(SLBC)为例,在分析工作原理的基础上,指出该变换器在连续导通模式(CCM)下开关电感单元电流与负载电流间存在六种与电感和占空比密切相关的匹配关系,同时存在负调现象。在断续导通模式(DCM)下开关电感单元电流与负载电流间仅存在一种对应关系,且不存在负调现象。该文分别在CCM和DCM下使用状态空间平均法和全阶模型面积法建立SLBC的小信号模型,表明该变换器存在右半平面零点(RHPZ),系统特性类似于升压型DC-DC变换器。依据六种电流关系和RHPZ相对位置,给出电感、电容值的最佳选择区域,综合满足稳态纹波和动态响应需求。最后通过实验验证了该文理论分析的正确性。

关键词：开关电感 buck 小信号建模右半平面零点参数设计

A digitally controlled PWM/PSM dual-mode DC/DC converter

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Journal of Semiconductors 2011年第11期32卷 103-109页

作者：甄少伟张波罗萍侯思剑叶璟欣马骁 State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China

A digitally controlled pulse width modulation/pulse skip modulation （PWM/PSM） dual-mode buck DC/DC converter is proposed. Its operation mode can be automatically chosen as continuous conduction mode （CCM） or discontinuous conduction mode （DCM）. The converter works in PSM at DCM and in 2 MHz PWM at CCM. Switching loss is reduced at a light load by skipping cycles. Thus high conversion efficiency is realized in a wide load current. The implementations of PWM control blocks, such as the ADC, the digital pulse width modulator （DPWM） and the loop compensator, and PSM control blocks are described in detail. The parameters of the loop compensator can be programmed for different external component values and switching frequencies, which is much more flexible than its analog rivals. The chip is manufactured in 0.13 μm CMOS technology and the chip area is 1.21 mm^2. Experimental results show that the conversion efficiency is high, being 90% at 200 mA and 67% at 20 mA. Meanwhile, the measured load step response shows that the proposed dual-mode converter has good stability.

关键词： digital power PSM ADC digital proportion integration differentiation DPWM buck

Effects of electron radiation on commercial power MOSFET with buck converter application

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Nuclear Science and Techniques 2017年第3期28卷 30-34页

作者： Sheik Fareed Ookar Abubakkar Nor Farahidah Zabah Yusof Abdullah Dhiyauddin Ahmad Fauzi Norasmahan Muridan Nurul Fadzlin Hasbullah Department of Electrical and Computer Engineering International Islamic University Kuala Lumpur 53100Malaysia Industrial Technology Division Agency Nuclear MalaysiaKuala Lumpur 43000 Malaysia

Microelectronic power converters such as buck and boost converter are required to be tolerant to radiations including electron radiation. This paper examines electron radiation effects on the Ⅰ-Ⅴ characteristics of VDMOSFET and its corresponding effects in buck converter. Analysis of the electrical characteristics shows that after irradiation the threshold voltage and drain current for all VDMOSFETs degraded more than two orders of magnitude. The impact of this electrical degradation has been investigated in an application of typical buck converter circuit. The buck converter with n-channel switching transistor shows that after irradiation its output voltage increased with the drain current in the n-channel ZVN4424 A VDMOSFET, while the buck converter with p-channel switching transistor shows its output voltage decreased with the drain current in the p-channel ZVP4424 A VDMOSFET after irradiation.

关键词： VDMOSFET I–V characteristics Drain current buck converter Electron radiation

A fixed-frequency fast transient response DC–DC controller for VRMs

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Journal of Semiconductors 2013年第12期34卷 66-71页

作者：陈明阳赵梦恋吴晓波 Institute of VLSI Design Zhejiang University

A 2V-10A fast transient response DC-DC buck controller based on fixed frequency hysteresis control is presented. A carefully designed output voltage filter detects the output capacitor current change which helps the controller to respond immediately after load changes. Adaptive hysteresis control guarantees the switching frequency to be the same as the reference frequency by using a CCII-composed circuit and current mirrors. The controller is designed and fabricated in a TSMC 0.35 μm process. Simulation and test results show that this con- troller achieves a 20 μs settling time in one single switching cycle when load current changes from 1 A to the full load condition at 10 A.

关键词： fast response hysteretic control buck

串入并出LLC-buck变换器的控制策略研究

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陕西科技大学学报 2022年第3期40卷 157-163页

作者：杨奕罗巍鑫重庆理工大学电气与电子工程学院重庆400054 重庆市能源互联网工程技术研究中心重庆400054

串入并出结构LLC-buck变换器能够实现大幅降压与大电流输出.但该结构变换器具有功率分配比例不同、瞬态响应速度慢及控制器设计复杂的问题,为解决上述问题,提出了以模块buck变换器输出电压与电感电流纹波叠加的固定导通时间控制策略.电... 详细信息

串入并出结构LLC-buck变换器能够实现大幅降压与大电流输出.但该结构变换器具有功率分配比例不同、瞬态响应速度慢及控制器设计复杂的问题,为解决上述问题,提出了以模块buck变换器输出电压与电感电流纹波叠加的固定导通时间控制策略.电感电流纹波不受输出电容等效电阻的影响,能够更快反应变换器负载的变化状态.首先介绍了变换器拓扑结构及特点,分析了各部分变换器的特性及控制策略的工作原理,并对控制器进行了稳定性分析.最后进行了仿真以及实验验证.结果表明,该控制策略应用于此相较传统PI控制具有更好的负载瞬态响应调节性能.

关键词：串联输入并联输出 LLC buck 瞬态响应控制策略

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低压大电流多相buck电路的研究与设计

低压大电流多相buck电路的研究与设计

作者：吴振滔华中科技大学

学位级别：硕士

随着片上系统的发展以及各种智能电子设备的快速普及,用于给各种电子设备提供可靠电压的电源管理芯片在过去几十年得到了较快的发展。如人们日常使用的电脑、手机和电子手表等电子设备的电源管理芯片尺寸越来越小,续航时间以及电源的安... 详细信息

随着片上系统的发展以及各种智能电子设备的快速普及,用于给各种电子设备提供可靠电压的电源管理芯片在过去几十年得到了较快的发展。如人们日常使用的电脑、手机和电子手表等电子设备的电源管理芯片尺寸越来越小,续航时间以及电源的安全可靠性都大幅提升。但是电源管理芯片也有着进步的空间,比如随着计算机运算性能越来越好,高速CPU的电流需求越来越大而且为了适应CPU更快的速度其输入电压也要越来越小。但是目前传统的电源管理芯片不能同时满足低压大电流的需求,对于低压大电流电源管理芯片的研究迫在眉睫。本文受到多相交错并联技术的启发,重点研究了电流峰值模式控制和多相并联技术结合的控制技术,提出了一种基于电流内环电压外环的电流峰值控制模式以及通过延时锁相环实现主从路均流方案的新型电路结构。输出端的分压网络和误差放大器实现输出电压的锁定。功率管的压降经过电流检测放大电路进入电流环和误差放大器输出作比较来控制功率级。这种电流模式的控制结构简化了补偿网络,只需要在误差放大器输出端放置二型补偿就可以保证系统的稳定性。本文重点对延时锁相环、PWM比较器以及误差放大器进行了分析和设计,其中锁相环中使用了校正模块解决了锁相环锁定周期错误的问题,PWM比较器不仅有高增益还有很快的响应速度避免了延时对环路的影响,高增益大带宽的误差放大器保证了输出电压的精度和和稳定。上述模块的电路设计基于华虹0.35μm BCD工艺,通过Cadence软件对电路进行了设计和仿真。整体的buck电路输入电压范围是3～5.5 V,输出电压范围是1.1～2 V,其输出电流最大为18 A且只有50 m A的电感电流纹波,稳定时buck开关频率是300k Hz,最高可达到92%的效率,对负载跳变有很快的响应,各相电流误差不超过0.5 A,多相并联技术让输出电流纹波变为了单相的10%左右,总的输出电流是单相的6倍,为低压大电流buck电路提供了可能。

关键词：低压大电流多相并联电流模式 buck

Modeling and Dynamic Analysis of Fractional-Order buck Converter in Continuous Conduction Mode

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Journal of Harbin Institute of Technology(New Series) 2019年第4期26卷 58-68页

作者： Dawei Ding Zongzhi Li Nian Wang School of Electronics and Information Engineering Anhui University

According to the fact that the actual inductor and actual capacitor are fractional, the mathematical and state-space averaging models of fractional order buck converters in continuous conduction mode(CCM) are constructed by using fractional calculus theory. Firstly, the parameter conditions that ensure that the converter working in CCM is given and transfer functions are derived. Also, the inductor current and the output voltage are analyzed. Then the difference between the mathematical model and the circuit model are analyzed, and the effect of fractional order is studied by comparing the integer order with fractional order model. Finally, the dynamic behavior of the current-controlled buck converter is investigated. Simulation experiments are achieved via the use of Matlab/Simulink. The experimental results verify the correctness of theoretical analysis, the order should be taken as a significant parameter. When the order is taken as a bifurcation parameter, the dynamic behavior of the converter will be affected and bifurcation points will be changed as order varies.

关键词： buck converter fractional order continuous conduction mode(CCM) modeling dynamic analysis bifurcation