| T O P I C R E V I E W |
| MarcL |
Posted - Jul 06 2012 : 14:08:07
Hi all,
I've been trying FastCap & FastHenry for a little moment, now, but both separately. I have understood pretty much how each simulator work, but I still have a few question, about the use of FastCap simulation.
First I would like to know if it is possible to use self and mutual capacitance obtained, and put them in spice format. For example to couple an air capacitor to other passive components.
Thank you for your help |
| 5 L A T E S T R E P L I E S (Newest First) |
| Enrico |
Posted - Jul 30 2012 : 23:25:27
quote:
If I process the file with convertHenry, and build an appropriated lst file, I notice some apertures in the meshing.
So I am not sure the calculated capacitance would be correct.
convertHenry is somewhat a simple tool, so yes you may have apertures, depending on the original source FastHenry2 file. If this is an issue or not depends on the resulting model and on your application. If the geometric perturbation is small, the overall accuracy should not be impacted, but this cannot be a general rule.
quote:
Basically, I would like to have a closed volume, surrounding the wire, like in the _1x1Bus example.
Do I need to refine the discretization of the coating? Enhance the number of segments? Use another mesher ?
To get accurate capacitance results, you should always refine the discretizations until your results converge. Using FastCap2 you must do it by hand. FasterCap on the other hand performs the task for you.
Best Regards,
Enrico
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| MarcL |
Posted - Jul 16 2012 : 10:02:14
Thanks again, Enrico !
Another question about a bended wire.
The wire is described as a segmented line, and coated with a dielectric.
Here's a portion of the FH code
quote:
.Units mm
.Default sigma=5.8e+4 nwinc=5 nhinc=5
NA01 x=46.7784 y=8.2483 z=0
NA02 x=44.6354 y=16.246 z=0
NA03 x=41.1362 y=23.75 z=0
NA04 x=36.3871 y=30.5324 z=0
NA05 x=30.5324 y=36.3871 z=0
NA06 x=23.75 y=41.1362 z=0
NA07 x=16.246 y=44.6354 z=0
NA08 x=8.2483 y=46.7784 z=0
NA09 x=0 y=47.5 z=0
NA10 x=-8.2483 y=46.7784 z=0
NA11 x=-16.246 y=44.6354 z=0
NA12 x=-23.75 y=41.1362 z=0
EA01 NA01 NA02 w=2 h=1
EA02 NA02 NA03 w=2 h=1
EA03 NA03 NA04 w=2 h=1
EA04 NA04 NA05 w=2 h=1
EA05 NA05 NA06 w=2 h=1
EA06 NA06 NA07 w=2 h=1
EA07 NA07 NA08 w=2 h=1
EA08 NA08 NA09 w=2 h=1
EA09 NA09 NA10 w=2 h=1
EA10 NA10 NA11 w=2 h=1
EA11 NA11 NA12 w=2 h=1
NB01 x=46.7784 y=8.2483 z=0
NB02 x=44.6354 y=16.246 z=0
NB03 x=41.1362 y=23.75 z=0
NB04 x=36.3871 y=30.5324 z=0
NB05 x=30.5324 y=36.3871 z=0
NB06 x=23.75 y=41.1362 z=0
NB07 x=16.246 y=44.6354 z=0
NB08 x=8.2483 y=46.7784 z=0
NB09 x=0 y=47.5 z=0
NB10 x=-8.2483 y=46.7784 z=0
NB11 x=-16.246 y=44.6354 z=0
NB12 x=-23.75 y=41.1362 z=0
EB01 NB01 NB02 w=5 h=3
EB02 NB02 NB03 w=5 h=3
EB03 NB03 NB04 w=5 h=3
EB04 NB04 NB05 w=5 h=3
EB05 NB05 NB06 w=5 h=3
EB06 NB06 NB07 w=5 h=3
EB07 NB07 NB08 w=5 h=3
EB08 NB08 NB09 w=5 h=3
EB09 NB09 NB10 w=5 h=3
EB10 NB10 NB11 w=5 h=3
EB11 NB11 NB12 w=5 h=3
.external NA01 NA12
.freq fmin=1e4 fmax=1e4 ndec=1
.end
If I process the file with convertHenry, and build an appropriated lst file, I notice some apertures in the meshing.
So I am not sure the calculated capacitance would be correct.
Basically, I would like to have a closed volume, surrounding the wire, like in the _1x1Bus example.
Do I need to refine the discretization of the coating? Enhance the number of segments? Use another mesher ?
Some advices would be appreciated
Best Regards |
| Enrico |
Posted - Jul 14 2012 : 23:58:17
Yes, the same goes for FastHenry2 - in this case you have the option to use a lumped R-L model, or a more sophisticate frequency-dependent subcircuit (automatically created by FastHenry2)
Best Regards,
Enrico
|
| MarcL |
Posted - Jul 11 2012 : 13:09:14
Dear Enrico,
Thanks for your answer.
So, "basically", the results provided by FastCap can be used in a spice simulator. I guess I have mixed too much informations, and was unable to summarize.
Best Regards |
| Enrico |
Posted - Jul 10 2012 : 00:37:33
I suggest you start with the paper "The Maxwell Capacitance Matrix", available for free download under the 'literature' page, 'white papers' section.
Best Regards,
Enrico
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