Re: Circuit Simulators, PsSpice & APLAC

From: 	John H. Couture[SMTP:couturejh-at-worldnet.att-dot-net]
Sent: 	Thursday, December 04, 1997 1:39 AM
To: 	Tesla List
Subject: 	Re: Circuit Simulators, PsSpice & APLAC

At 06:15 AM 12/3/97 +0000, you wrote:
>From: 	Scott Stephens[SMTP:stephens-at-enteract-dot-com]
>Sent: 	Tuesday, December 02, 1997 4:35 PM
>To: 	Tesla List
>Subject: 	Circuit Simulators, PsSpice & APLAC
>Any of you use Microsim's PS SPice or APLAC to simulate TC's? Transformer?
>Switching supplies?
>I've got the leech-ware (free) versions of both (available on the net). You
>can design and evaluate most components. I'm especialy impressed with APLAC
>and it's ability to allow parasitics in modeling inductors (so it can give
>you self-resonant frequency,) and also the TORRIOD statement, that includes
>saturation, air gap, and all relevant parameters related to transformer
>design. Aplac can even do EM simulation! Which would realy be nice to
>evaluate a TC oil submerged or potted, with a ferrite core!
>Microsim has EZ windowz interface, but doen't have the versitility APLAC
>seems to. I'm just starting to learn the language. My purpose is to avoid my
>usual expensive impirical development path, paved with dead semi's.
>So, got any scripts? Advice?

  Scott -

  The Handbook for Electrical Engineers states that Tesla coil design is
empirical. This means that a TC must be designed by both theory and data
from actual coil tests. This type of design is required for all complex
engineering systems. In other words programs like PC Spice must also be
supplemented by empirical design data.

  For example the miles per gallon for a new automobile design must be done
by empirical design. This is necessary because it is not possible to
theoretically determine all of the frictional losses in the car, etc. etc.
without using data from actual tests. 

  With the JHCTES TC computer program I have attemped to use theory and
actual test data to simulate Tesla coils for sizes from 18 watts to 60 KW.
The program also has several important features including automatic tuning.
When you make a change, all of the relevant parameters are changed to keep
the system in tune. Interestingly, this has confused some coilers because
the program will not let them use certain combinations of parameters where
the TC would not in tune. 

  I have been told that the program is very good but needs more features.
There are no other TC programs like it even though the program can be
improved. I understand there are coilers working on similar programs but
they have not finished them.

   John Couture