主题：关于FEMM 4.0

感觉FM里面的音圈卷宽不能做细微的调节，SPEAD里面又是计算值一般都比实际值小（导致BL一般偏大）。改数据库的话重装软件的时候又要重做一遍，太麻烦了，其他还是可以的。

另外，个人实践认为FEMM里面的模拟B值要比SPEAD里面的小好多（但有做实验SPEAD里面的和实际样品很接近），不知道各位是否遇到过这种情况

请教下lingyi，FineMotor里面的磁路好象都是比较规矩的，是否可以直接将FEMM里面的磁路数据导入，而不需要再在FineMotor里面设置磁路规格等参数？

受用了.......謝過.

FINEMotorMagnetMaterialFile
Version=1.0
** All lines starting with ** are seen as comments
** The 2 first lines above are required and must NOT be erased or changed.
Parameters
**The next 3 lines must be the name and 2 magnet material parameters:
Name=Y30 Ferrite/Ceramic 5
Br=3900
Hl=3714
**Note: Br (G) is the Remanence in Gauss (1G=0.0001T)
**Note: Hl (Oe) is the Coercivity in oersted for B=0 (Extrapolated load line).
**Note: Hl=Br/urec - urec is recoil permeability
** 1[kA/m]=4*pi[Oe]
EndParameters
** Use these lines to add your own comments.
** More lines starting with ** can be added
** Then the list of magnet sizes should follow with no blanks or comment lines.
Sizes : (OD; ID; Length;Name)
 36.0; 18.0;  6.0;  36 x  18 x  6
 45.0; 22.0;  8.0;  45 x  22 x  8
 55.0; 24.0;  8.0;  55 x  24 x  8
 55.0; 24.0; 12.0;  55 x  24 x 12 
 60.0; 24.0;  9.0;  60 x  24 x  9 
 60.0; 24.0; 12.0;  60 x  24 x 12 
 60.0; 30.0; 10.0;  60 x  30 x 10 
 72.0; 32.0; 10.0;  72 x  32 x 10 
 72.0; 32.0; 12.0;  72 x  32 x 12 
 72.0; 32.0; 15.0;  72 x  32 x 15 
 84.0; 32.8; 15.0;  84 x  33 x 15 
 90.0; 36.0; 17.0;  90 x  36 x 17 
 90.0; 42.0; 17.0;  90 x  42 x 17 
100.0; 45.0; 18.0; 100 x  45 x 18 
102.0; 42.0; 17.0; 102 x  42 x 17 
102.0; 51.0; 18.0; 102 x  51 x 18 
102.0; 51.0; 20.0; 102 x  51 x 20 
102.0; 57.0; 17.0; 102 x  57 x 17 
110.0; 45.0; 18.0; 110 x  45 x 18 
110.0; 57.0; 20.0; 110 x  57 x 20 
121.0; 42.0; 20.0; 121 x  42 x 20 
121.0; 57.0; 17.5; 121 x  57 x 17.5
121.0; 57.0; 20.0; 121 x  57 x 20 
134.0; 57.0; 20.0; 134 x  57 x 20 
224.0;122.0; 23.0; 224 x 122 x 23 
EndSizes

FINEMotorMagnetMaterialFile
Version=1.0
** All lines starting with ** are seen as comments
** The 2 first lines above are required and must NOT be erased or changed.
Parameters
**The next 3 lines must be the name and 2 magnet material parameters:
Name=N38SH Neodymium
Br=12300
Hl=11400
**Note: Br (G) is the Remanence in Gauss (1G=0.0001T)
**Note: Hl (Oe) is the Coercivity in oersted for B=0 (Extrapolated load line).
**Note: Hl=Br/urec - urec is recoil permeability
** 1[kA/m]=4*pi[Oe]
EndParameters
** Use these lines to add your own comments.
** More lines starting with ** can be added
** Then the list of magnet sizes should follow with no blanks or comment lines.
Sizes : (OD; ID; Length;Name)
18;0;3; 18x3
25;0;3; 25x3
31;0;4; 31x4
37;0;5; 37x5
EndSizes

SPEAD里面有没有内磁的材料库?

好象SPEAD是不能算内磁的哦

可以直接将FEMM里面的磁路数据导入,不需要再在FineMotor里面设置磁路规格等参数.

还有。FineMotor的磁铁参数库可以自己建立的。

请问在哪里可以设置，谢谢！

设置什么？

别设置了，自定义还来得快

此主题相关图片如下：

搞定！已经可以使用！D版的也可以哦！！！

FEMM感觉挺好的,主要的还是免费!

出了新版本，比老版本易操作性要强些了，还没有仔细看

 
The inductance of an air core solenoid coil can be calculated with Wheeler's formula:

L (microhenries) =	0.8 * N^2 * R^2          6*R + 9*L + 10*B
N = total number of turns R = average radius = (inner radius + outer radius)/2 L = coil length (along the axis) B = thickness of the winding = outer radius - inner radius Refer to Figure 1 below. (all dimensions in inches)
Alternatively, for dimensions in millimeters:
L (microhenries) =	0.0315 * N^2 * R^2         6*R + 9*L + 10*B

---

Figure 1

For the analysis of magnetic fields, I highly recommend a finite element analysis program called "FEMM" (Finite Element Methods Magnetics). This very useful program was written by Dr. David Meeker and version 3.1 is available free at his web site. Be sure to get the tutorial by Ian Stokes-Rees. This tutorial has very detailed step-by-step examples using FEMM. If you have been using version 2, version 3 has some new features that you'll fine useful and the data files are formated to make them easier to read, in case you want to change a parameter with a text editor. The .fem files are plain text, so you can view and edit them with any text editor, such as Notepad. It also includes a very powerful scripting capability.

The project editor incorporated in FEMM is good, however, if you make changes to an existing project file, you may want to save it with a different name before running the analysis in case you decide to revert back to the original design. FEMM as the peculiarity of writing the source file to disk with the original file name before it does an analysis.

The FEMM message board is an excellent source of additional information about magnetic problems.

Here is another example using FEMM, with graphical and numerical results.

此帖要顶，

争取打造成FEMM 普及的学习讨论第一贴

偶也来顶一个，正学

还是　买吧