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原子教你玩STM32视频配套PPT
原子教你玩STM32视频配套PPT 共30讲
- 2021-05-06下载
- 积分：1
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自适应对消滤波MATLAB实现
自适应对消滤波MATLAB实现，可以对消噪声提取有用信号
- 2020-12-03下载
- 积分：1
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平面变压器3D仿真资料
采用COMSOL软件，对平面变压器的仿真过程进行叙述，让大家了解平面变压器的仿真流程，是个很好的指导教材Solved with COMSOL Multiphysics 5.0Results and discussionThe magnetostatic analysis yields an inductance of 0. 1l mH and a dc resistance of0. 29 mQ2. Figure 2 shows the magnetic flux density norm and the electric potentialdistributionvolume: Coil potentiaL()Volume: Magnetic flux density norm (t▲0.07▲2.88×10-42.51.50.03050.01V656×107v0igure 2: Magnetic flux density norm and electric potential distribution for themagnetostatic analysisIn the static (DC) limit, the potential drop along the winding is purely resistive andcould in principle be computed separately and before the magnetic flux density iscomputed. When increasing the frequency, inductive effects start to limit the currentand skin effect makes it increasingly difficult to resolve the current distribution in thewinding. At sufficiently high frequency, the current is mainly flowing in a thin layernear the conductor surface. When increasing the frequency further. capacitive effectscome into play and current is flowing across the winding as displacement currentdensity. When going through the resonance frequency, the device goes from behavingas an inductor to become predominantly capacitive. At the self resonance, the resistivelosses peak due to the large internal currents Figure 4 shows the surface current3 MODELING OF A 3D INDUCTORSolved with COMSOL Multiphysics 5.0distribution atl MHz. Typical for high frequency the currents are displaced towardsthe edges of the conductor.freq(1)=1.0000E6_Surfaee: Surface-current density norm (A/)▲18618Q16010￥1.02Figure 3: Surface current density at I MHz (below the resonance frequency)Figure 4 shows how the resistive part of the coil impedance peaks at the resonancefrequency near 6MHz whereas Figure 5 shows how the reactive part of the coiimpedance changes sign and goes from inductive to capacitive when passing throughthe resonance4 MODELING OFA3DINDUCTORSolved with COMSOL Multiphysics 5.0Global: Lumped port impedance(Q2)d port impedance7.5G6.583275655545352510.10.20.30.40.509igure 4: Real part of the electric potential distribution5 MODELING OF A INDUCTORSolved with COMSOL Multiphysics 5.0Global: Lumped port impedance(Q2)35000Lumped port impedance200001000050000500010000-1500020000250000.10.20.30.40.50.60.70.809Figure 5: The reactive part of the coil impedance changes sign hen passing through theresonance frequency, going from inductive to capacitiveModel library path: ACDC_Module/Inductive_ Devices_and_coils/inductor 3dFrom the file menu. choose newNEWI In the new window click model wizardMODEL WIZARDI In the model wizard window click 3D2 In the Select physics tree, select AC/DC> Magnetic Fields(mf)3 Click Add4 Click StudyMODELING OF A3D NDUCTORSolved with COMSOL Multiphysics 5.05 In the Select study tree, select Preset Studies>StationaryGEOMETRYThe main geometry is imported from file. Air domains are typically not part of a CaDgeometry so they usually have to be added later. For convenience three additionaldomains have been defined in the CAd file. These are used to define a narrow feed gapwhere an excitation can be appliedport l(impl)I On the model toolbar, click Import2 In the Settings window for Import, locate the Import section3 Click Browse4 Browse to the models model library folder and double-click the filenductor 3d. mphbinSphere /(sphl)I On the Geometry toolbar, click Sphere2 In the Settings window for Sphere, locate the Size section3 In the Radius text field, type 0.2ick to expand the Layers section. In the table, enter the following settingsLayer nameThickness(m)ayer0.055 Click the Build All Objects buttonForm Union(fin)i On the Geometry toolbar, click Build AllClick the Zoom Extents button on the Graphics toolbar7 MODELING OF A 3D INDUCTORSolved with COMSOL Multiphysics 5.03 Click the Wireframe Rendering button on the Graphics toolbarThe geometry should now look as in the figure below0.1-0.10.20.0.0.1y0.0.2Next, define selections to be used when setting up materials and physics Start bdefining the domain group for the inductor winding and continue by adding otheruseful selectionsDEFINITIONSExplicitI On the Definitions toolbar, click Explicit2 In the Settings window for Explicit, in the Label text field, type Winding3 Select Domains 7,8 and 14 onlyI On the Definitions toolbar, click Explicit2 In the Settings window for Explicit, in the Label text field, type Gap3 Select domain 9 onlI On the Definitions toolbar, click Explicit8 MODELING OF A3DINDUCTORSolved with COMSOL Multiphysics 5.02 In the Settings window for Explicit, in the Label text field, type core3 Select Domain 6 onlyExplicit 4I On the Definitions toolbar, click Explicit2 In the Settings window for Explicit, in the Label text field, type InfiniteElements3 Select Domains 1-4 and 10-13 onlyExplicit 5I On the Definitions toolbar, click Explicit2 In the Settings window for Explicit, in the Label text field, type Non-conducting3 Select Domains 1-6 and 9-13 onlyI On the Definitions toolbar, click Explicit2 In the Settings window for Explicit, in the Label text field, type Non-conductingwithout Ie3 Select Domains 5, 6, and 9 only.Infinite Element Domain /(iel)Use infinite elements to emulate an infinite open space surrounding the inductorI On the definitions toolbar click Infinite element domain2 In the Settings window for Infinite Element Domain, locate the Domain Selectionsection3 From the Selection list. choose Infinite Elements4 Locate the Geometry section From the Type list, choose SphericalNext define the material settingsADD MATERIALI On the Model toolbar, click Add Material to open the add Material window2 Go to the Add material window3 In the tree, select AC/DC>Copper.4 Click Add to Component in the window toolbar9 MODELING OF A 3D INDUCTORSolved with COMSOL Multiphysics 5.0MATERIALSCopper(mat/)I In the Model Builder window, under Component I(comp l)>Materials click Copper(matD)2 In the Settings window for Material, locate the Geometric Entity Selection section3 From the Selection list, choose windingADD MATERIALI Go to the Add Material window2 In the tree. select built-In>Air3 Click Add to Component in the window toolbarMATERIALSAir(mat2I In the Model Builder window, under Component I(comp l)>Materials click Air(mat2)2 In the Settings window for Material, locate the Geometric Entity Selection section3 From the Selection list, choose Non-conductingThe core material is not part of the material library so it is entered as a user-definedmateriaMaterial 3(mat3)I In the Model Builder window, right-click Materials and choose Blank Material2 In the Settings window for Material, in the Label text field, type Core3 Locate the geometric Entity Selection section4 From the selection list choose Core5 Locate the Material Contents section. In the table, enter the following settingsPropertName Value Unit Property groupElectrical conductivity sigma0S/IBasicRelative permittivity epsilonrBasicRelative permeability mur1e3Basic6 On the model toolbar. click Add Material to close the Add Material windowMAGNETIC FIELDS (MF)Select Domains 1-8 and 10-14 only0MODELING OF A 3D INDUCTOR
- 2020-12-10下载
- 积分：1
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matlab在时间序列建模预测及程序代码
详细介绍了时间序列建模及预测过程，包括算法，也包括一些matlab工具箱中的代码计算结果表明,时,预测的标准误差较小,所以选取=。预测第月份的销售收入为计算的程序如卜为移动平均的项数由于的取值不同,的长度不一致,下面使用了细胞数组简单移动平均法只這合做近期预测,而且是预测目标的发展趋势变化不人的情况如果目标的发展趋势存在其它的变化,米用简单移动屮均法就会产生较大的预测偏差和滞后。加权移动平均法在简单栘动平均公式中,每期数据在求平均时的作用是等同的。但是,每期数据所包含的信息量不样,近期数据包含着更多关于未来情况的信息。因此,把各期数据等同看待是不尽合理的,应考虑各期数据的重要性,对近期数据给予较大的权重,这就是加权移动平均法的基本思想。设时间序列为加权移动平均公式为十·十∴+式中为期加权移动平均数;为的权数,它体现了相应的在加权平均数中的重要性。利用加权移动平均数来做预测,其预测公式为即以第期加权移动平均数作为第+期的预测值。例我国年原煤广量如表所示,试用加权移动平均法预测年的产量。表我国原煤产量统计数据及加权移动平均预测值表原煤产量三年加权移动平均预测值相对差(%)解取,按预测公式计算三年加权移动平均预测值,其结果列于表中。年我国原煤产量的预测值为(亿吨这个预测值偏低,可以修正。其方法是:先计算各年预测值与实际值的相对误差,例如年为将相对误差列于表中,再计算总的平均相对误差。由于总预测值的平均值比实际值低,所以可将年的预测值修正为计算的程序如下:在加权移动平均法中,的选择,同样具有一定的经验性。一般的原则是:近期数据的权效人,远期数据的权数小。至于人到什么稈度和小到什么程度,则需要按照预测者对序饥的了解和分析来确定。趋势移动平均法简单移动平均法和加权移动平均法,在时间序列没有明显的趋势变动时,能够准确反映实际情况。但当时间序列出现直线増加或减少的变动趋势时,用简单移动平均法和加权移动平均法来预测就会岀现滞后偏差。因此,需要进行修正,修正的方法是作二次移动平均,利用移动平均滞后偏差的规律米建立直线趋势的预测模型。这就是趋势移动平均法。次移动的平均数为+∴在一次移动平均的基础上再进行一次移动平均就是二次移动平均,其计算公式为D下面讨论如何利用移动平均的潛后偏差建立直线趋势预测模型。设时间序列从某时期开始具有直线趋势,且认为末来时期也按此直线趋势变化,则可设此直线趋势预测模型为其中为当前时期数;为由至预测期的时期数;为截距;为斜率。两者又称为平滑系数现在,我们根据移动平均值来确定平滑系数。由模型()可知所以+…十因此由式(),类似式()的推导,可得所以类似式()的推导,可得于是,由式()和式()可得平滑系数的计算公式为例我国年的发电总量如表所示,试预测和年的发电总量。表我国发电量及一、二次移动平均值计算表年份发电总量次移动平均二次移动平均,=解由散点图可以看出,发电总量基本呈直线上升趋势,可用趋势移动半均法来预测。图原始数据散点图取三,分别计算次和二次移动平均值并列于衣中。再由公式(),得于是,得时直线趋势预测模型为预测年和年的发电总量为计算的程序如下:把原始数据保存在纯文本文件中为移动平均的项数趋势移动平均法对于冋时存在直线趋势与厝期波动的序列,是种既能反映趋势变化,又可以有效地分离出来周期变动的方法。§指数半滑法次移动平均实际上认为最近期数据对未来值影响相同,都力权一;而期以前的数据对未来值没有影响,加权为。但是,二次及更高次移动平均数的权数却不是—,且次数越高,权数的结构越复杂,但永远保持对称的权数,即两端项权数小,中间项权薮大,不符合一般系统的动态性。一般说来历史数据对未来值的影响是随时间间隔的增长而递减的。所以,更切合实际的方法应是对各期观测值依时间顺序进行加权平均作为预测值。指数平滑法可满足这一要求,而且具有简单的递推形式指数平滑法根据平滑次数的不同,又分为一次指数平滑法、二次指数平滑法和三次指数平滑法等,分别介绍如下次指数平滑法.预测模型设时间序列为,a为加权系数,
- 2020-12-06下载
- 积分：1
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分布式电源接入对配电网的影响
MATLAB仿真的分布式电源接入对于配电网的影响，有疑问可以私信我。
- 2020-11-04下载
- 积分：1
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动态规划算法经典例题
一些动态规划，最新最典型的算法！如，背包问题，钢管切割问题，最长子序列问题等等。
- 2020-12-11下载
- 积分：1
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ad6 altium designer封装库大全封装集合常用元件电阻电容继电器等封装库protel
用于ad altium designer 6以上的 ad6.9 ad 6.9 的封装库大全，封装集合，下载，包含常用的电阻电容电感，可调电阻电容，等封装，继电器，插件直插封装大全，以及一些常用元件三极管等的原理图符号图，类似protel dxp封装库。各个封装 footprint
- 2020-12-04下载
- 积分：1
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预测控制（席裕庚）
MPC领域经典书籍，上海交通大学席裕庚老师主编预测控制
- 2021-05-06下载
- 积分：1
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开关磁阻电机调速系统的仿真模型
在MATLAB/Simulink环境下，建立了SRD系统仿真仿真模型，包括SRD模型、变流器的模型和位置传感器的模型等。
- 2020-07-02下载
- 积分：1
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Delphi之TClientSocket和TServerSocket进行TCP长连接通讯使用KeepAlive自动发送心跳包检测...
【实例简介】Delphi之TClientSocket和TServerSocket进行TCP长连接通讯，使用KeepALive自动发送心跳包检测断网，并实现断线重连，经测试可以及时检测到拔掉网线断网情况，具有较高的参考价值
- 2021-11-18 00:47:15下载
- 积分：1
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