ansoft Maxwell 3d教程.pdf
ansoft Maxwell 3d 向导式的用户界面、精度驱动的自适应剖分技术和强大的后处理器时的Maxwell 3D成为业界最佳的高性能三维电磁设计软件。可以分析涡流、位移电流、集肤效应和邻近效应具有不可忽视作用的系统,得到电机、母线、变压器、线圈等电磁部件的整体特性。功率损耗、线圈损耗、某一频率下的阻抗(R和L)、力、转矩、电感、储能等参数可以自动计算。同时也可以给出整个相位的磁力线、B和H分布图、能量密度、温度分布等图形结果。本文件是软件使用教程.希望能帮助大家·Printing HistorNew editions of this manual include material up dated since theprevious edition. The manual printing date, indicating the manualscurrent edition, changes w hen a ncw edition is printed. Minorcorrections and updates incorporated al reprint do not cause the daleto changeUpdate packages may be issued betw een editions and containadditional and/ or rep lacement pages to be merged into the manualby the user Pages which are rearranged because of changes on aprevious page are not considered to be revised.EditionDateSoftwareRevisionFebruary 1991April 199212December 1993October 19964.1September 19995.06December 20006.0WWW⊥nmTypeface ConventionsComputerCter type is used fon promptsand messages, for field names, and for keyboard entries that must be ty ped in theirentirety exactly as shown. For example, thenstruction"copy filel"means to type the w ordcopy, to type a space. and then to type filelMenu/Command Computer type is also used to display the commands that are needed to perform a specifictask Menu levels are separated by forwardslashes (/) For example, the instructionhoose File/Open"means to choose the Opencommand under the file menuItalicsItalic type is used for emphasis and for thetitles of manuals and other publications. Italictype is also used for key board entries when aname or a variable must be typed in place ofthe words in italics. For example, the instruc-rion“ copy filename” means to type the wordcopy, to type a space, and then to type then amc of a filc. such as filelKeysHelvetica type is used for labeled keys on thecomputer keyboard. For example, the instruc-tion"Press Return?"means to press the key onthe com puter that is lahcled Returnwww.docin.coInstallationBefore you use Maxwell 3D, you must1. Set up your systems graphical windowing systerm2. Install the Maxwell softw are, using the directions in theAnsell PC or UNIX Installation guideIf you have not yet done these steps, refer to the ansoft installetionguides and the documentation that came w ith your computer systemor ask your system administrator for helpsing a Graphical User InterfaceIf you are familiar with the concepts of using a mouse, menus, andother graphical user interface(GUn)tools, skip to Chapter 1“ IntroductionIf you have not used GuI systems before, this section will help youunderstand some of the terminology used in this guide. Since GUIare basically visual, the best way to learn to use them is by practicingon your systemMost gui systcms usc a mouseas a poinTing device, with whichyou can select areas on the screenfor command execution andmoving from one program toanother. Your mouse may have 2www.door 3 buttons; Maxwell 3D ignoresthe middle button on 3-buttondelsAnsoft products donot usc this button. You canprogram mouse buttons to work in non-standard ways, as you mightwant to if you are left-handed. For simplicity, the left-hand hutton(under your forefinger if you are right-handed) is called the leftbutton, and the one on far right is the right mouse button. You willprobably find the terms intuitive once you use these buttons a fewtimesPoint and click; Right clickTo choose an item with the mouse, first move it on your desk until thearrow cursor is on that item; you are now pointing" at the item. Next,ress and release the left bu tton thlled"clicking " Point-andclick is the most common action you will make with your mouseally, click" refers to a lefise button clickYou can sometimes use your right mouse button to access or entercommands. In the 3d Modeler for instance, a right mouse buttonclick causes a short menu of commands to appear at the moustcursor. Generally, right click "refers to a right mouse button clickDouble-ClickOccasionally you may want to sclect all of thc text in a box,orperform a special lask(such as indicating the end of drawing a linewhile you are using Maxwell 3D. You can do this efficiently byquickly clicking twice with your left mouse button -a doubleDragging objects; Click and HoldWhen you are drawing in the 3D Modeler, you can often use yourmouse to enter objects and move around the screen. Frequently, youwill click the mouse button and hold it down until the next part of thecommand is reached (the object is oved, the next point is enteredand so forth). If you click and hold on the edge of a w indow, you canposition, or drag, the window on your screen. You can often dragobjects in Maxwell; experiment to see w hat will moveTool BarsTool bars are shortcut methods for entering commands. There is atool bar in the 3d Modeler and most of the setup modules for severalcommand s. To use a tool bar. click the mouse cursor on the buttonyou want to use. Here is an example of a tool bar囗。圖哦良风≌固函MenusWithin each screen of maxwell 3d are areas w hich list subsets ormenus,of commands. You can access a menu by clicking your mouseon the word or button that indicates the menu. The menu is pulleddown, listing the commands available on that menu. (For examplethc New command is availablc on the File mcnu. Usually, thc mcnuwill remain displayed until you choose a command, or click on thedesktop to exit. If the menu does not remain displayed, click and holdthe mouse button, then release the button to make your choiceFile Edit viewNewopenCloseSavectrl+SSave AsImportExportExitctrl+QAn arrow on the right side of a command indicates that there is asubmenu for that command. An ellipsis (. )indicates that a pop-upwindow appears aftcr choosing this commandWhen you are asked to use a menu command, each level is separatedby a"/". Thus, to zoom in on a drawing, you would choose the viewLoom In menu command To open a new file, you would choose File/There are also pop-up menus, which appear when you righL-click ona maxwell modeler window. choose commands from thcsc menus inthe same way as from menu barsFor more information on using GUIs, refer to"User Interface"in theMaxwell Control Panel,s online help systemOther ReferencesFor detailed information on Maxwell 3d commands refer to theonline documentation for the maxwell 3d field simulatorTo start maxwell 3d, you must first access the maxwell controlPanel. for more detailed inform ation on the maxwell control panelcommands, refer to the Maxwell Control Panels online help systemwww.docin.comTable of Contents1. Introduction1-1General Procedure.1-2The Sample Problem1-4Meshes.....,,,,,,,,面2. Create aAccess the maxwell Control Panel·:.·:·甲,,,,,,,,,,2-2Start the Project managerCreate a Project directoryCreate a New project··,···············,·,,,,,,,,,,2-6Enter notes2-73. Draw the model3-1Open the project3-2Start. the 3D Modeler3-3Side window........................snaps3-6Define the problem region: Coordinates and Units ..,...... 3-7Absolute and relative coordinates3-7Grids3-7Zooming in and out of the view window3-9Create the electromagnet3-10Draw the Coil...,,.,..,3-10Draw thc Circlc........,..,...,,,......,..........3-10Create the Cylinder,,3-11Create the hole for the Core3-12Draw the Core·中··············3-13SavingP3-14Create the magnel翻...3-15Draw the magnet3-15Move the magnet3-15Toggle Off the Background..................3-16Create a termini..........,,,,,..,,,,......,,,..3-17Create the Coil terminal..........,,......,,,.,..3-18Define the Problem Region;..,;;“;##.3-20Define the Problem Region .................. 3-21Shading and rendering . ......................................3-22Exit the 3d modeler3-234 Define The problemAccess the Material Manager4-2Exclude the background·····+···,,,,,,,,,,,,,,.4-2Assign Steel to the CoreAssign Copper to the Coil4-3Assign vacuum to the problem Region.......4.......4-3Assign NdFe35 to the Magnet4-3Access the 3D Boundary/Source Manager45assign a current to the coil.....4-6Define the sourceAssigning the Source lo the Termina.........,..,,,,∴4-64-7Check the Direction of the CurrentExit the 3D Boundary/Source Manager4-85. Generate a Solution5-1Setup executive Parameters······5-2Create a Force Setup for the Magnet.5-3Create a Force Setup for the Coil and Core5-3Create a Force Setup for the entire model·········Exiting the Executive Parameters moduleSpecifying Solution Criteria·非5-5Solver type11翻自。■非非首·····:.··.·Magnetic Field SolveResidualSolve for Field and Parameters+++++++++++++++++++++;,+“++Adaptive analysisContents-2
- 2020-11-27下载
- 积分:1
ARMA模型的详细介绍与举例
详细介绍ARMA模型 里面不仅介绍了该模型的实际用法也进行了举例分析计算结果表明,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,
- 2020-12-05下载
- 积分:1