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Reflected Power




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From:  Harri Suomalainen [SMTP:haba-at-cc.hut.fi]
Sent:  Monday, January 26, 1998 2:43 PM
To:  tesla-at-pupman-dot-com
Subject:  Re: Reflected Power

>I'm in the process of rewinding the secondary of the output
>transformer of my flyback converter. In an attempt to match the
>impedence of the Tesla coil I'm adding more turns. Are there any ham
>radio operators on the list that knows what reflected power looks
like
>on a O,scope? I've been seeing a strange waveform on the scope and I

Unfortunately there is no visual difference in reflected and real
power.
Compare it with reflected image on a mirror and the real one.
However,
reflected power is *not* absorbed by the coil and it should just
increase
your curculated power and increase amplitudes of current (and
voltage).
It may have some phase-shift related with it too.

>   This is a representation of the waveforms I'm seeing when I
increase
>the voltage applied to the circuit (things were so much easier when
I
>was driving a resistive load!).

Well, the coil should draw current pretty much sinuoidally when
exited
by a resonant frequency drive. Monitoring current will tell you a
lot.
Once you are at resonance it should draw sinuoidal half cycle while
the transistor is conducting (like in the forward mode converter) and
waveform in the off-time depends on lots of things, especially the
voltage
waveform.


--
Harri Suomalainen     mailto:haba-at-cc.hut.fi

We have phone numbers, why would we need IP-numbers? - a person in a
bus