XANSYS Forum Index
    Register    

FAQ    Search    Memberlist    Usergroups    SmartFeedSmartFeed    Profile    Log in
[Xansys] [EMAG] dynamic rotor of PMSM in transient analysis
 
This forum is locked: you cannot post, reply to, or edit topics.   This topic is locked: you cannot edit posts or make replies.    XANSYS Forum Index -> XANSYS
Author Message
mike.yaksh
User


Joined: 05 Feb 2009
Posts: 291

PostPosted: Wed Mar 14, 2012 10:06 am  Reply with quote

Grzegorz,

If you are going to feed the stator with currents without any 124's, you can use the 13 for the entire model; As you indicated, a simple approach would be to move the mesh at some angular increment based on rotor speed. You are asking about letting the code do the motion based on the torque applied to the rotor by Maxwell's stress forces. The Maxwell stress force tends to be more accurate for the rotor with the magnets (near free space) than for the stator with permeability's above 500. There is not much control needed if you have a 360 degree model. But if you have some type periodic model, you will need to reset the rotor when it reaches the boundary. For the stator you need only the AZ, but for the rotor side you would need keyopt(1)=4 which uses the AZ and the structural Dofs.

For such problems, I find it simpler to just use AZ and move the mesh with NGEN

If you are using 124s, then you will need 53 for the stator windings. If you have two or more coil cross sections in a slot, they cannot share nodes between the cross section since you have to CP the EMF CURR dofs. I have used 53 and 13 in the same model to keep the node count down; if so, mesh the areas with the 13 first, then the slots with the 53s. A paper was presented at a previous ANSYS conference for generator simulations where there were diodes and other elements for 3 phase generator. I will send it to you.

Mike Yaksh
NAC International
Norcross GA

-----Original Message-----
From: xansys-bounces@xansys.org [mailto:xansys-bounces@xansys.org] On Behalf Of G. Sawczuk
G. Sawczuk <glsawczuk@o2.pl>
Sent: Wednesday, March 14, 2012 10:55 AM
To: xansys@xansys.org
Subject: [Xansys] [EMAG] dynamic rotor of PMSM in transient analysis

Welcome everybody,

I'd like to carry out the simulations of permanent magnet synchronous motor (odd periodic symmetry case or even one) in ANSYS Classic considering dynamic effects (magnetic + structural).

Facts:
magnetic elements
plane53 or plane13 to coupling with structural
circu124

structural elements
???

How can I rotate my interior permanent magnet rotor at variable rotational velocity (first I will calculate my step time from angular speed and angle)?
I don't want to use a scaling commands e.g. "agen" like I do in the static analysis. I want to use structural elements and define a motor speed to see e.g. flux density vectors at every load substep time.
I seem I must change my elements from magnetic to structural and then define some properties, to save physics and in the next step read to solve next magnetic analysis.
Could somebody help me in this topic? Maybe you have some macros for example.


Regards,
Grzegorz Sawczuk
The Silesian University of Technology (SUT) Gliwice, POLAND


+-------------------------------------------------------------+
| XANSYS web - www.xansys.org/forum |
| The Online Community for users of ANSYS, Inc. Software |
| Hosted by PADT - www.padtinc.com |
| Send administrative requests to xansys-mod@tynecomp.co.uk |
+-------------------------------------------------------------+

Post generated using Mail2Forum (http://www.mail2forum.com)
Back to top
View user's profile Send private message
przemys-aw.siedlaczek
User


Joined: 21 Oct 2008
Posts: 91

PostPosted: Wed Mar 14, 2012 10:18 am  Reply with quote

For coupling different field analysis (inertia structures motion due to
Magnetic generated forces) the ANSYS MFS solver would be the best
choice. It can couple EMAG and MECHANICAL elements in one simulation
i.e. for starting or braking.
Alternatively you can use ANSYS MAXWELL for magnetic-motion coupling.

--
Przemyslaw Siedlaczek
__
MESco
PL 42-600 Tarnowskie Go'ry ul.Go'rnicza 20a
tel: +48/32/768-36-36 fax:+48/32/768-36-35
http://www.mesco.com.pl mailto: info@mesco.com.pl

On 2012-03-14 15:55, G. Sawczuk wrote:
Quote:
Welcome everybody,

I'd like to carry out the simulations of permanent magnet synchronous motor (odd periodic symmetry case or even one) in ANSYS Classic considering dynamic effects (magnetic + structural).

Facts:
magnetic elements
plane53 or plane13 to coupling with structural
circu124

structural elements
???

How can I rotate my interior permanent magnet rotor at variable rotational velocity (first I will calculate my step time from angular speed and angle)?
I don't want to use a scaling commands e.g. "agen" like I do in the static analysis. I want to use structural elements and define a motor speed to see e.g. flux density vectors at every load substep time.
I seem I must change my elements from magnetic to structural and then define some properties, to save physics and in the next step read to solve next magnetic analysis.
Could somebody help me in this topic? Maybe you have some macros for example.


Regards,
Grzegorz Sawczuk
The Silesian University of Technology (SUT)
Gliwice, POLAND


+-------------------------------------------------------------+
| XANSYS web - www.xansys.org/forum |
| The Online Community for users of ANSYS, Inc. Software |
| Hosted by PADT - www.padtinc.com |
| Send administrative requests to xansys-mod@tynecomp.co.uk |
+-------------------------------------------------------------+



Post generated using Mail2Forum (http://www.mail2forum.com)
Back to top
View user's profile Send private message
grzegorz.sawczuk
User


Joined: 21 Oct 2008
Posts: 6

PostPosted: Wed Mar 14, 2012 11:42 am  Reply with quote

Thanks Przemyslaw,

I know about ANSYS Multi-Field Solver, just today I've read some about one. Have you got any specific not general ideas to solve my problem? How can I connect magnetic and structural problem in APDL. Can you present me an step-by-step algorithm?
I have already calculated a mentioned problem in Maxwell, but now I want solve it in ANSYS.

Grzegorz Sawczuk
The Silesian University of Technology (SUT)
Gliwice, POLAND


Quote:
For coupling different field analysis (inertia structures motion due to
Magnetic generated forces) the ANSYS MFS solver would be the best
choice. It can couple EMAG and MECHANICAL elements in one simulation
i.e. for starting or braking.
Alternatively you can use ANSYS MAXWELL for magnetic-motion coupling.

--
Przemyslaw Siedlaczek
__
MESco
PL 42-600 Tarnowskie Go'ry ul.Go'rnicza 20a
tel: +48/32/768-36-36 fax:+48/32/768-36-35
http://www.mesco.com.pl mailto: info@mesco.com.pl
Back to top
View user's profile Send private message
grzegorz.sawczuk
User


Joined: 21 Oct 2008
Posts: 6

PostPosted: Wed Mar 14, 2012 11:57 am  Reply with quote

Thanks Mike,

I have already used 124 with 53 to solve a transient problem (magnetizing of permanent magnets). But it was a fixed model and I've not used any structural elements. Now, I need couple my magnetic analysis with structural, but I really don't know how can I rotate my IPM rotor. I have got one paper (is shared by ANSYS) but reading one I didn't see any part about rotor sliding. Only I know that it must be possible and that's all what I know.

Grzegorz Sawczuk
The Silesian University of Technology (SUT)
Gliwice, POLAND


Quote:
Grzegorz,

If you are going to feed the stator with currents without any 124's, you can use the 13 for the entire model; As you indicated, a simple approach would be to move the mesh at some angular increment based on rotor speed. You are asking about letting the code do the motion based on the torque applied to the rotor by Maxwell's stress forces. The Maxwell stress force tends to be more accurate for the rotor with the magnets (near free space) than for the stator with permeability's above 500. There is not much control needed if you have a 360 degree model. But if you have some type periodic model, you will need to reset the rotor when it reaches the boundary. For the stator you need only the AZ, but for the rotor side you would need keyopt(1)=4 which uses the AZ and the structural Dofs.

For such problems, I find it simpler to just use AZ and move the mesh with NGEN

If you are using 124s, then you will need 53 for the stator windings. If you have two or more coil cross sections in a slot, they cannot share nodes between the cross section since you have to CP the EMF CURR dofs. I have used 53 and 13 in the same model to keep the node count down; if so, mesh the areas with the 13 first, then the slots with the 53s. A paper was presented at a previous ANSYS conference for generator simulations where there were diodes and other elements for 3 phase generator. I will send it to you.

Mike Yaksh
NAC International
Norcross GA
Back to top
View user's profile Send private message
grzegorz.sawczuk
User


Joined: 21 Oct 2008
Posts: 6

PostPosted: Wed Mar 14, 2012 11:33 pm  Reply with quote

Hi Mike,

Thank you very much for your e-mail and an example. Regarding ngen command I use in my load macro:

r_shift=arg1-r_last[/i] ! arg1=r_ang, r_last- last rotor position

alls
csys,0
cedele,all

*if,r_ang,ne,0,then
!----------------- Rotating of rotor ----------------------------
*if,r_shift,ne,0,then
alls
csys,1
cmsel,s,rtr_a
alls,belo,area
arscale,all,,,1,r_shift,,,,1
alls
csys,0
*endif

*do,n,1,Poles ! new esys for PMs
local,20+n,0,,,,-90+r_ang+(n-1)*360/Poles
*enddo
*endif


in the coupling macro I use:

cmsel,s,rtr_cp ! inner rotor nodes
cmsel,s,str_cp ! stator elements
ceintf,0.20,az,,,,,,0.10


The effect is the same after use ngen or agen, arscale in this case (when IMOVE=1).
I'm sending to you a paper that I've found. This is what I need (page 9) but I really don't know how define an angular velocity on my rotating part. In the paper using special macro oddslide.

Kind regards,
Grzegorz


Quote:

... then I add the elements with cmsel,,cee and then
ceintf. I then move the cen1 nodes back
Mike
Back to top
View user's profile Send private message
grzegorz.sawczuk
User


Joined: 21 Oct 2008
Posts: 6

PostPosted: Thu Mar 15, 2012 12:27 pm  Reply with quote

Has somebody any ideas to solve my problem of dynamic IPM rotor in a transient analysis?
_________________
Grzegorz Sawczuk
The Silesian University of Technology (SUT)
Gliwice, POLAND
Back to top
View user's profile Send private message
danbohlen
User


Joined: 18 Aug 2008
Posts: 951
Location: Evendale OH

PostPosted: Thu Mar 15, 2012 12:51 pm  Reply with quote

Yes, I do.


Dan Bohlen
Senior Staff Engineer, Military HPT Analysis
GE Aircraft Engines
6380 Aviation Way
West Chester, OH  45069
(NP2 Pod "B" 2nd floor desk #135)
M/D  W217  513-672-6360
Dial Comm *892-6360 



-----Original Message-----
From: xansys-bounces@xansys.org [mailto:xansys-bounces@xansys.org] On Behalf Of grzegorz.sawczuk
Sent: Thursday, March 15, 2012 3:28 PM
To: xansys@xansys.org
Subject: Re: [Xansys] [EMAG] dynamic rotor of PMSM in transient analysis

Has somebody any ideas to solve my problem of dynamic IPM rotor in a transient analysis?

------------------------
Grzegorz Sawczuk
The Silesian University of Technology (SUT) Gliwice, POLAND






+-------------------------------------------------------------+
| XANSYS web - www.xansys.org/forum |
| The Online Community for users of ANSYS, Inc. Software |
| Hosted by PADT - www.padtinc.com |
| Send administrative requests to xansys-mod@tynecomp.co.uk |
+-------------------------------------------------------------+

Post generated using Mail2Forum (http://www.mail2forum.com)
_________________
Dan Bohlen
Senior Staff Engineer
GE Aircraft Engines
Back to top
View user's profile Send private message
Display posts from previous:   
This forum is locked: you cannot post, reply to, or edit topics.   This topic is locked: you cannot edit posts or make replies.    XANSYS Forum Index -> XANSYS
All times are GMT - 7 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You cannot download files in this forum


Powered by phpBB © 2001, 2005 phpBB Group

sleek template created by Andrew Charron