[TCML] Calculate Output Voltage

[Antonio Carlos M. de Queiroz]

Mddeming at aol.com wrote:
> You're right. It's Wrong. That formula is correct for non-resonant,  
> iron-core transformers with coupling coefficient close to 1.00. A better  theoretical 
> value is Vs=Vp x sqrt(Ls/Lp), where L is the inductance, and  this is an upper 
> limit. Hitting 80% of this value requires a very well  designed and tuned 
> coil.
Not completely wrong, as inductance is always proportional to the square 
of the number of turns.
If it were possible to wrap a primary coil along all the length of the 
secondary coil, the voltage
gain would be close to the turns ratio, as both coils would have almost 
the same geometry.
But as the coils don't have the same geometry, the voltage gain is the 
turns ratio multiplied
by a constant, smaller than 1, that depends on the exact geometry. The 
voltage gain can also
be written as sqrt(Cs/Cp), where Cs is the total secondary capacitance 
and Cp the primary
capacitance. As LsCs=LpCp for a correctly tuned coil, the result is the 
same.

Antonio Carlos M. de Queiroz