In article ,
Winston wrote:

Joseph Gwinn wrote:
In ,
wrote:

(...)

That all looks inductively reactive to me.

Then there is problem with the spice model. More below.

Joe, I did the experiment in the real world just now.

You are right. With a resistive load on the secondary
I saw undetectable phase shift between voltage and
current on the primary. With an inductively reactive
load on the secondary, I saw the expected significant
lag in the current peak in relation to the voltage peak
on the primary.

That will be what I learned today and I thank you.

(...)

War story: Many years ago, I was interested in the physics of xenon
flash lamps. The physical model is pretty simple, a charged capacitor
discharging into an arc, which arc heated the xenon to incandescence,
the resulting light and heat radiation carrying the energy away. This
yields a set of coupled ordinary differential equations that one solves
numerically, time step by time step. I got it all working, and all was
well. Then I changed the duration of the time steps, and more energy
came out as light and heat than was stored in the capacitor. Oops.
Violated the conservation of energy.

Turns out I had made two mathematical mistakes, which mistakes cancelled
one another only for the original step duration.

Wow!
That one must have had you scratching your head for a while!

It did. If only I could patent it, I could be rich and famous.
Boundless power source. I would have settled for rich.

More seriousy, models can be dangerous.


Joe Gwinn