Re: eddy current with secondary coil

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "chris swinson" <exxos-at-cps-games.co.uk> 

HI Terry, all,

thanks for the links, will check them out :)

IS there anyway to find the proximity effect for optimal distance for the
secondary turns ? There might be some simple rule or guide which states the
effect is double the wire size or something ?  I would like to try a better
space wound coil though the proximity effect will be greatest as the wire
gets closer, as it gets further it must be less, but does this mean at 1mm
spacing its 50% less and 2mm its 70% less or does it just stop at 2mm
spacing, very confusing I think...

Chris


----- Original Message -----
From: "Tesla list" <tesla-at-pupman-dot-com>
To: <tesla-at-pupman-dot-com>
Sent: Sunday, October 05, 2003 6:25 PM
Subject: Re: eddy current with secondary coil


 > Original poster: Terry Fritz <teslalist-at-twfpowerelectronics-dot-com>
 >
 > Hi Chris,
 >
 > I am note sure there is a "nice" program to do such things.
 >
 > Here are some papers which deal with this:
 >
 > http://engineering.dartmouth.edu/other/inductor/papers.shtml
 >
 > Go to the ones under Litz wire.
 >
 > All the papers under "Magnetics Design" are pertinent if one's brain can
 > comprehend them...
 >
 > Paul has done vast work in this area too:
 >
 > http://www.abelian.demon.co.uk/tssp/
 >
 > Finding the "Q" of a secondary is very messy:
 >
 > http://www.abelian.demon.co.uk/tssp/qvar070402/
 >
 > So far, there is no wonderful way to predict it with high accuracy.  It is
 > dramatically affected by too many obnoxious things...
 >
 > Cheers,
 >
 >          Terry
 >
 >
 >
 >
 > At 09:58 AM 10/5/2003, you wrote:
 > > > Low-frequency inductances and mutual inductances. Most of the
 > > > formulations that I used assume uniform current in the wires,
 > > > radially and along them.
 > > >
 > > > Skin and proximity effects have some effect on inductances, but
 > > > the most serious deviation from the DC values in this case is
 > > > caused by the capacitances of the coils changing the currents
 > > > along the wires. It's easy to take this into account, if the
 > > > current profiles are known, but this is not implemented in my
 > > > program yet. The program developed by Paul Nicholson (Acmi) can
 > > > take the current profiles into account.
 > > > Eventually I will look at this problem, but I would like to find
 > > > first a good method to calculate the current profiles.
 > > >
 > > > Antonio Carlos M. de Queiroz
 > > >
 > > >
 > >
 > >
 > >Is there a program which will calculate secondary coils with space
windings
 > >? and maybe even further do the math to work out various resistance and
 > >current effects of litz wire also ?
 > >
 > >Chris
 >
 >
 >
 >