[Prev][Next][Index][Thread]
Re: TC Electrostatics (fwd)
Tesla List wrote:
>
> > > Subject: Re: TC Electrostatics (fwd)
> > Subject: Re: TC Electrostatics (fwd)
> > > Subject: Re: TC Electrostatics (fwd)
>
> Subscriber: hullr-at-whitlock-dot-com Thu Jan 2 22:56:37 1997
> Date: Thu, 02 Jan 1997 17:22:41 -0800
> From: Richard Hull <hullr-at-whitlock-dot-com>
> To: tesla-at-pupman-dot-com
> Subject: Re: TC Electrostatics (fwd)
>
> Tesla List wrote:
> >
> > > Subject: Re: TC Electrostatics (fwd)
> >
> > Subscriber: bert.hickman-at-aquila-dot-com Mon Dec 23 13:54:40 1996
> > Date: Mon, 23 Dec 1996 10:33:28 -0800
> > From: Bert Hickman <bert.hickman-at-aquila-dot-com>
> > To: tesla-at-pupman-dot-com
> > Subject: Re: TC Electrostatics (fwd)
> >
> > Tesla List wrote:
> > >
> > > Subscriber: rwall-at-ix-dot-netcom-dot-com Sun Dec 22 20:25:57 1996
> > > Date: Sun, 22 Dec 1996 14:08:41 -0800
> > > From: Richard Wayne Wall <rwall-at-ix-dot-netcom-dot-com>
> > > To: tesla-at-pupman-dot-com
> > > Subject: Re: TC Electrostatics (fwd)
> > >
> > > 12/22/96
> > >
> >
> >
> > Richard, Alfred, and all,
> >
> > Interesting insights, Alfred. Conservation of energy holds for Tesla
> > Coils (and most other things on Chip's list!). :^)
> >
> > Richard, trying to change Cs "on the fly", although conceptually
> > correct, would be virtually impossible due to the combination of high
> > voltages and rapid switching required. Fortunately we don't need to do
> > this - there are easier ways! Merely increasing primary capacitance, gap
> > breakdown voltage, reducing secondary capacitance, or improving transfer
> > efficiency will all increase output voltage, as long as the overall
> > system is retuned appropriately. These interrelationships are shown
> > below.
> >
> > The initial energy available "per bang" in the primary circuit is:
> >
> > Ein = 1/2 (CpVg^2)
> >
> > The maximum energy we'll can get out of the secondary will be:
> >
> > Eout = 1/2(CsVs^2) = Ein - Losses (all types)
> >
> > Losses include spark gap, resistance and skin effect, secondary ground
> > path resistance, premature corona/streamer generation, and radiated
> > energy. We'll ignore how efficiency might be measured - we just want to
> > see its effect on output voltage. If we let X represent the "transfer
> > efficiency" associated with moving energy from the primary to the
> > secondary, then:
> >
> > Eout = X*Ein.
> >
> > Now, solving for output voltage Vs:
> >
> > Vs = Vg*SQRT(X*Cp/Cs)
> >
> > Note that, as Alfred suggests, exactly HOW we transfer this energy does
> > not really matter! A Tesla coil simply does it electromagnetically.
> >
> > Implications:
> > Increasing Cp, Vg, and X, or decreasing Cs will increase Vs. However, Vs
> > increases linearly with increasing Vg, but only as the square-root of
> > the ratio of Cp/Cs. Large systems tend to significantly increase both Vg
> > and Cp, while only moderately increasing Cs (to protect the secondary
> > and prevent breakout at higher voltages). Not obvious from the simple
> > equations above is that while increasing Cs may reduce output voltage,
> > it may increase overall coil performance and sparklength for a variety
> > of other reasons! Trying to maximize output voltage is not the whole
> > story.
> >
> > While there's no such thing as a free lunch, you can get most of what
> > you pay for... if you're careful! :^)
> >
> > Safe coilin' to you, and Season's Greetings!
> >
> > -- Bert --
>
> Bert,
>
> I think the key issue here was dv/dt and its analog, in this case d
> charge/dt. The varying capacity of the system's air load in operation
> was the source of ES energy, as posited by Alfred, and the
> electromagnetic part of the Tesla coil is just the tranlational device to
> achieve this end. I would always conserve the energy and charge. The
> primary cap increase would obviously increase the capabilities of the
> system from spark to charge output. The key would seem to be to get the
> capacitve loading of the air to wiggle with greater amplitude. Lots ta'
> chew on here.
>
> Richard Hull, TCBOR
I agree. Alfred's post relating influence machines and a TC from a
capacitor ratio-energy balance standpoint was an interesting spin that I
hadn't previously considered, but which makes perfectly good sense. A
different way of looking at things....
-- Bert --