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Search Results: 1 - 10 of 56455 matches for " 胡雪峰 "
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电容钳位型单相不对称三电平逆变器及其空间矢量脉宽调制方法
Study of SVPWM Method for Single-Phase Asymmetric Three-Level Capacitance- Clamped Inverter
 [PDF]

王琳, 雪峰
Electromagnetic Analysis and Applications (EAA) , 2014, DOI: 10.12677/EAA.2014.33004
Abstract:
本文提出一种适用于电容钳位型单相不对称三电平逆变器空间矢量脉宽调制(space vector pulse width modulation, SVPWM)方法。该方法将单相空间矢量图分为4个区间,根据伏秒平衡原理,利用区间内的两个电压矢量实现对输出参考电压矢量的合成。为了滤除输出电压中所含有的谐波,获得更接近正弦波的波形,采用的LC滤波器去滤除输出电压中含有的谐波,并给出了LC参数的设计方法。仿真结果证明,所提逆变器及其SVPWM控制方法具有良好的性能。
In this paper, the space vector pulse width modulation (SVPWM) method was proposed for the topology of single-phase asymmetric three-level inverter. Based on the proposed method, the sin-gle-phase space vector diagram is divided into four regions, and the output reference voltage vector is synthesized by the two voltage vectors of the region according to the volt-second balance principle. In order to filter harmonic which is contained in the output voltage and create better sine wave, LC filter is widely used in the design to filter harmonic of the output voltage, and a parameter design method is developed for the inductor and capacitor designs. The good performance of the proposed inverter and SVPWM control method is demonstrated by the simulation results.
南方网纹红土多元成因的粒度证据
雪峰
科学通报 , 2005,
Abstract: 对宣城、九江、泰和和赣州网纹红土粒度特征的研究表明:(1)宣城和九江两地的网纹红土,粒度均匀而细小,不含>2mm的砾石;>63μm细砂粒的平均含量分别为0.30%和1.14%;而10~50μm粒组明显富集,平均分别为34.65%和37.20%.剖面上部黄棕色土的粒度频率分布曲线与北方黄土和下蜀黄土很相近;其余各层的频率分布曲线与前者也有明显的继承性.剖面各层石英颗粒粒度频率分布曲线十分一致,与北方黄土和下蜀黄土有很好的可比性.这些特征均反映了两地网纹红土明显的风成特性.(2)泰和、赣州网纹红土粗颗粒含量较高;各粒级组分在层次间变化明显;10~50μm粒组富集不明显.红土原样和红土石英颗粒粒度频率分布曲线与北方黄土和下蜀黄土缺乏可比性,表现出明显的冲、洪积相特征.(3)网纹红土成因的多元性反映了南方第四纪环境的多样性和复杂性.风成特性网纹红土的存在为南方第四纪冰期风尘堆积提供了实物证据.对这类红土分布区域的进一步调查和研究,有助于揭示南方第四纪冰期大规模风尘堆积的南界.
一种用于LED照明中的组合式Boost-Cuk变换器
A Combined-Type Boost-Cuk Converter for LED Lighting System
 [PDF]

王琳, 章家岩, 雪峰
Instrumentation and Equipments (IaE) , 2014, DOI: 10.12677/IaE.2014.22002
Abstract:
本文提出了一种基于Boost拓扑与Cuk拓扑有机组合思路的适用于LED照明系统中的组合式Boost-Cuk变换器,Boost环节与Cuk环节共用输入支路,使该变换器通过一个开关管同时实现两路输出,一路输出为Boost型,另一路输出为Cuk型。Boost环节与Cuk环节的输出串联,提高了该变换器的输出电压增益。为了灵活控制输出,只需一个控制器便可以实现多种方式的输出。仿真结果证明该拓扑结构性能与理论分析一致。
A Combined-type Boost-Cuk converter for LED lighting system was proposed based on the combi-nation of Boost and Cuk topologies. The converter using a switch can simultaneously achieve two kinds of output by sharing the branch of the input side of the two topologies mentioned. One of the outputs for the converter is Boost-type, and the other one is the Cuk-type. The voltage gain of the converter is improved with the output of Boost and Cuk topologies proposed in series connected. In order to control the output, only one controller can achieve the output in various ways. The si-mulation results are given to verify the consistence between the performance and theoretical analysis of the topology.
普通克里金法在海水温度剖面插值中的应用
Application of Ordinary Kriging method in the interpolation for seawater temperature profile

雪峰,长青
- , 2015, DOI: 10.16300/j.cnki.1000-3630.2015.05.001
Abstract: 海水温度剖面在水声学领域扮演着重要的角色,而目前大面积实时温度剖面测量能力尚存不足,因此对于海水温度剖面的网格插值研究就有一定的意义。基于普通克里金法对某海域获得的剖面样本进行插值,通过逐点逐面的拟合最终得到该海域三维温度场。通过拟合温度剖面和部分样本剖面的对比,证实普通克里金法对于海水温度剖面拟合具有很好的效果,具有应用的可行性。
Seawater temperature profile plays an important role in underwater acoustics, while the ability of acquiring instant temperature profile in a large area is far from sufficient. Based on MATLAB, the Ordinary Kriging method is used to interpolate profiles acquired from a certain sea area point-to-point and surface-to-surface into a three-dimensional temperature field. Contrasting the interpolated profiles with the acquired ones, the OK method is tested to be effective for fitting the temperature profile with highly feasibility.
光伏并网逆变器的直接预测控制策略及其DSP实现
雪峰,龚春英
电工技术学报 , 2011,
Abstract: 逆变器是光伏并网发电系统的核心设备之一,本文提出了一种用于单相光伏并网逆变器的并网电流所需占空比预测控制策略。该方法是在逆变器状态方程的基础上,推导出实现单位功率因数并网运行的占空比控制函数,从而直接对光伏并网逆变器的输出电流进行控制。该方法的特点是把光伏电池输出的直流电压,电网电压引入占空比的计算中,能有效地防止光伏电池输出电压容易波动的影响,同时实现了电网电压的前馈。另外整个系统中不需设计常规并网逆变器控制策略中的PI控制器,使得控制结构简单,系统的动态响应快。仿真和实验结果证明了该方法的有效性和实用性。
适用于光伏/燃料电池发电的组合式直流升压变换器
雪峰,龚春英
中国电机工程学报 , 2012,
Abstract: 光伏/燃料电池并网发电系统是目前可再生能源应用领域的重要研究方向,然而上述2类电源的直接输出电压较低,通常需要一高升压变比的直流变换器将其提升到较高电压来供给并网逆变器,但直流变换器的高频纹波电流又会影响上述2类电源的使用寿命和工作效率,针对上述问题提出一种组合式直流升压变换器,给出了该变换器的2种控制方法——互补控制和交叉移相控制,分析了该变换器在每种控制策略时的工作原理和基本特性。通过一台1kW的原理样机,验证了该变换器具有以下特点:较高的升压变比,可以有效降低主开关管的电压应力和输入电流纹波,同时具有较小的输出电压纹波。
应用神经网络和重复控制的逆变器综合控制策略
雪峰,谭国俊
中国电机工程学报 , 2009,
Abstract: 针对脉宽调制(pulsewidthmodulation,PWM)逆变电源控制系统,提出一种基于(diagonalrecurrentneuralnetwork,DRNN)在线自整定PID控制和改进重复控制相结合的新型综合控制策略,给出PID参数在线自整定的控制算法和改进重复控制器的设计参数。利用改进重复控制改善系统的稳态性能,利用对角递归神经网络在线自整定PID控制提高系统的动态性能,既能克服常规控制逆变器波形跟踪性能差的不足,又能极大改善重复控制逆变器动态响应滞后的问题。实验结果表明,该综合控制策略能实现逆变器的快速动态响应和高精度稳态输出波形。
云南智能电网建设浅析
Analysis of Yunnan Smart Grid Construction
 [PDF]

赵盛萍, 王达达, 谭向宇, 张少泉, 雪峰, 田雷
Smart Grid (SG) , 2013, DOI: 10.12677/SG.2013.32008
Abstract:
云南电网肩负着云南电力供应和电力外送双重任务,自身结构复杂。本文通过分析云南电网现状,对比云南电网与智能电网要求的差距,提出在云南智能电网的建设中要注意:设备是系统的基础,要加强实时、自动化、电器和用户的交互式技术的开发,建设与智能电网相适应的电力市场。
Yunnan power grid has a complex structure and shoulders the dual task of local power supply and power ex-port. In this paper, by analyzing the Yunnan power grid status quo and comparing Yunnan power grid with the smart grid, Yunnan smart grid construction should be advised: as the device is the basis of the system, it is necessary to strengthen the development of real-time automation, the interactive technologies between the electrical appliance and the users, and construct the electricity market which is suitable for the smart grid.
云南新能源发电分析研究
Analytical Investigation of New Energy Power Generation in Yunnan Province
 [PDF]

雪峰, 于靖微, 谭向宇, 高亚静, 赵盛萍, 田雷
Smart Grid (SG) , 2013, DOI: 10.12677/SG.2013.34017
Abstract:
面对日趋严重的环境污染和资源枯竭问题,经济环保的新能源发电越来越多地受到人们的重视。云南风能、太阳能、生物质能及页岩气等新能源储量巨大,开发潜力可观。本文从云南开发新能源的优势和挑战两方面分析了云南新能源发展遇到的问题,分析介绍了一种适合云南电网特点的风光储互补发电系统。
Facing the increasingly serious problems of environmental pollution and resource depletion, new energy power generation which is economic and environmental attracts more and more attention of us. Yunnan Province has huge reserves of new energy, such as wind, solar, biomass, and shale gas, and its potential development is considerable. This paper analyzes the problems of new energy development in Yunnan Province from two aspects: advantages and challenges in the development of new energy, and introduces a kind of wind-light-storage complementary system which is suitable for the characteristics of Yunnan power grid.
几何精确的非协调等几何NURBS有限元
雪峰,马正东,
固体力学学报 , 2012,
Abstract: 本文尝试将传统的非协调有限元技术推广到等几何有限元领域,建立了基于精确几何的非协调等几何分析方法,旨在拓展等几何分析应用范围,以便于等几何分析技术能真正实现CAD和FEA的融合,从而真正实现了无需划分网格的目的。我们定义了非协调的NURBS几何(类似非协调元),给出了NURBS曲面之间几何弱连续的充分条件,进而定义了非协调的等几何分析,将之归纳为带约束驻值问题,并用拉格朗日方法进行求解。两个算例证明这种方法的有效性。未来的工作主要是证明这种方法在不同几何连续性条件下的收敛性以及将之应用到更广的领域。
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