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Re: TC Program Factors (was How to rise the secondary? (vmax x power)) (fwd)



---------- Forwarded message ----------
Date: Thu, 23 Jul 1998 04:24:38 +0000
From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
To: Tesla List <tesla-at-pupman-dot-com>
Subject: Re:  TC Program Factors  (was How to rise the secondary?   (vmax x power))


  Bert, All -

  You are correct about the loss factor. However, that is only one small
part of the many factors necessary when making an empirical TC design
program. The loss factor is needed in the program because all theoretical
equations are based on 100% efficiency. I have found that this loss factor
varies from about 80% for small coils to about 10% for large coils. The
larger coils have greater losses because of the ultra high secondary
voltages compared to small coils. 

  A good way to compare the efficiency of Tesla coils is by the "watts per
foot of spark" method. It is a well known fact that the watts per foot of
spark increases as the TC size increases. The spark would have to be a
controlled spark, that is, a horizontal spark from the toroid to a ground
point. I show a graph in one of my books of percent efficiency vs watts per
foot of spark.

  In addition to the loss factor there are other factors required to make a
TC design program conform to real world coils. For example, increasing the
secondary inductance of a typical coil will increase the output spark for a
certain input watts. Decreasing the secondary radius of a typical coil will
decrease the output spark, other things being equal. It is obvious that
factors are required that include both gains and reductions when parameter
changes are made to a typical coil with a certain input watts.

  There is much more to an empirical TC design program than just a loss
factor to take care of the 100% efficiency problem of the theoretical
equations. These additional factors are the basis of empirical programs that
will make a theoretical equation conform to real coils. Finding these
factors is not a simple matter and takes much research of real coil tests.

  The accuracy of these factors determines how well the TC program will
design a coil that represents a proper working coil. These factors depend
not only on research but also on the engineering and coiling experience of
the programmer. This is why empirical TC design programs will vary in format
and accuracy with different programmers. That is also why I am interested in
what other programmers will develop in empirical type TC design programs.

  John Couture

------------------------------------------



At 09:33 PM 7/21/98 -0600, you wrote:
>
>
>---------- Forwarded message ----------
>Date: Mon, 20 Jul 1998 23:44:14 -0500
>From: Bert Hickman <bert.hickman-at-aquila-dot-com>
>To: Tesla List <tesla-at-pupman-dot-com>
>Subject: Re: How to rise the secondary?  (vmax x power) (fwd)
>
>John and all,
>
>The loss factor will always be less than 1.0 for a disruptive coil. Well
>designed systems may reach the 80%+ level...
>
>-- Bert --
>
>Tesla List wrote:
>> 
>> ---------- Forwarded message ----------
>> Date: Mon, 20 Jul 1998 05:58:29 +0000
>> From: "John H. Couture" <couturejh-at-worldnet.att-dot-net>
>> To: Tesla List <tesla-at-pupman-dot-com>
>> Subject: Re: How to rise the secondary?  (vmax x power) (fwd)
>> 
>>   Antonio, All -
>> 
>>   I was pleased to see that you added the "loss_factor" because most coilers
>> usually use only the theoretical equation.
>> 
>>   The "loss_factor" is the key that converts a theoretical equation into an
>> empirical equation that represents the real world coils. However, this
>> factor may be a loss or a gain depending on the TC parameters and how they
>> are changed.
>> 
><SNIP>
>
>
>