From: boris petkovic
Date: Fri, 22 Dec 2000 04:41:21 -0800 (PST)
Subject: Re: [TSSP] Final solution...great chance for it
> > > A mere 50 parts, that would be quite quick - at > > > least once > > > the Cext and Cint matrices are calculated - that > > > takes > > > a few hours on the cluster. Once Cint and Cext > are > > > obtained, with only 50 steps the solution for > each > > > omega is just a few seconds. > > ---- > > You're talking about computing times for CW state > or > > complited transients solved for every case in time > > domain? > > ---- > > Yes, that's the time taken to solve the network for > AC steady state conditions at a single frequency. > > > ----- I guessed you would say that. What about (computing time), simulating 100 turn coil response when step function applied ,say at pentium processor? ----- > > You know,once I thought that the only way except > > Maxwel field theory,for simulating the coils was > the > > method we are employing today (LC connected > network > > simulations). > > After seeing Bodlovic's work,and heard aboout > "dream" > > softwares he told me about I changed my mind. > > ----- > > The two approaches are equivalent when the free > space > wavelength of the frequencies involved are large > compared > with the dimensions of the secondary. --- I agree. --- > > Ultimately, both our and Bodlovic's methods will > boil > down to a finite element network solution involving > a > matrix of coefficients which relate the V and I of > the > elements. The difference I think will lie with how > the > coefficients are obtained. ----- Yes,I think you're right.In the technical paper you'll read ,he used some tricks in the matrix manipulation that significantly shorted computing time of the coefficients ,but that didn't spoiled a precision of final result.Everything he said seemed true,and for disc turn experimental coil he could even neglect non-adjanced turn capacities without loosing msm-theory agreement.Probably ,your hair standing up while you're reading this,but this is possible to do as concerns disk shape turn construction of very large comercial transformers. The purpose of his technical paper was not just to predict current and voltage waveforms over winding but to emphasize difference between standard (our),well known approach with the chain of coupled qudruples and his method. Physical background of the process is better explained in his case. ------ > > I'll refrain from further speculation until I've > seen > his paper. > > > ---- > > He gave me also one written in English that > > illustrates > > basical lines of his approach. > > He wasn't too happy when publisher insisted on > > transforming his field model into "flash and > bones" of > > distributed circuit where electrical and > magnetical > > parts are treated separately. > > Sounds like that amounts to dropping terms like the > d/dt integral(D.dA) mentioned above - ie removing > the direct E to B field coupling so that the two > fields > are independent and only coupled through the action > of > charge movement on the winding - see intro to > pn2511. > > > Such representation is incomplete,and some results > > derived from EM field approach are lost. > > Yes, eg far field radiation of EM energy - a few > tens > of mW for a 1kW coil. ----- Once,you re intersted in predicting Q of secondaries ,right? Now,I will ask you quite a diffucult question. What do you think could be the highest possible Q of the structure like Tesla's 100 turn 100"*100'' extra coil from CS? Imagine there is perfect ,loseless isolation,super conducting winding and enviroment,and the only losess comes becouse of radiating. I don't expect concrete number ,but try to guess the ballpark. ------ We can afford to ignore that. > We > also ignore the slight spiral 'twist' to the B field > occuring due to the longitudinal component of > current > flow. ----- Ignored in his technical paper too ,but in his Maxwel theory he took such effect in account. ---- > > However ,even the simplification was novelity,and > msms > > and model were in a good agreement. > > although his experimental comparisons must have been > for > particularly simple configurations in view of his > limited > accounting of external environment. > > > Give me your snail mail address. > > Paul Nicholson, > Middle Horsewood Cottage, > Lumbutts, > Todmorden, OL14 6HT > England. > > Thanks Boris, > -- > Paul Nicholson, > Manchester, UK. > -- __________________________________________________ Do You Yahoo!? Yahoo! Shopping - Thousands of Stores. Millions of Products. http://shopping.yahoo.com/
Maintainer Paul Nicholson, paul@abelian.demon.co.uk.