From billbeskimo.com Fri Aug 8 21:25:28 1997
Date: Fri, 8 Aug 1997 21:24:21 -0700 (PDT)
From: William Beaty
To: Tim Girard
Cc: freenrg-l@eskimo.com
Subject: RE: PODMOD, MRA, egos... ...power factor.
On Thu, 10 Jul 1997, Tim Girard wrote:
> Hi Bill,
> Can you explain the AC power factor to me. I must have missed it in the
> list somewhere.
Hi Tim! This was heavily discussed in 1994 on Keelynet, many people
here are already familiar.
It involves AC, coils, and capacitors. The short version: if volts and
current in an AC wave are at zero phase angle or 180deg phase, there is a
continuous energy flow in the pair of wires. But if the phase angle is
90deg or 270deg, there is no energy flow. So, if you ONLY measure voltage
and current, and ignore the phase between them, you know nothing about
energy flow. With AC systems, you cannot just measure volts, measure
current, then multiply to get wattage. That only works for pure DC.
THE LONG VERSION:
If you stick a resistor across an AC line, the voltage drives a
current, and when the voltage is high, the current is high, and the energy
flow (wattage) is high. When the voltage reverses every 120th second, the
current reverses too, so the wattage is still positive. The resistor gets
hot, and it actually is heated by two whacks of energy every 60th of a
second (heat is maxiumum when the voltage is positive AND when the voltage
is negative.) The energy waveform turns out to be a 120hz sine wave
flowing into the resistor as the volts and current keep reversing.
RESISTOR
voltage current energy
wave wave wave
. . .
+ + +
++ ++ ++++
+++ +++ +++++++++ VOLTS AND CURRENT VARY
+++ +++ +++++++++ TOGETHER DURING AC CYCLE,
++ ++ ++++ SO ENERGY ALWAYS FLOWS
+ + + FROM GENERTOR TO RESISTOR
. . .
- - +
-- -- ++++
--- --- +++++++++
--- --- +++++++++
-- -- ++++
- - +
_______________________________________________________________________
Now if you stick a capacitor across the AC line, something entirely
different happens. As the voltage wave cycles along, first there is a
tiny voltage and a large current as the capacitor charges. Then the line
voltage rises to maximum as the capacitor becomes fully charged, and the
current is zero when the voltage is maximum. The voltage then falls, and
the capacitor discharge causes a current which is reversed in polarity
compared to the first current. When the voltage is down to zero again,
this reversed current is maximum. The voltage then goes to negative
maximum, the capacitor charges in the opposite polarity, and when the
voltage gets to negative maximum , the capacitor is fully charged and the
current is again zero. The voltage then falls, and the capacitor current
reverses again as it discharges.
If we look at the energy flow (watts, or volts times current) around the
capacitor circuit, we find that it is very different than the energy flow
for the resistor. For the resistor, voltage and current both went
positive and negative at the same time, so energy flow was ALWAYS
positive, meaning that electrical energy flow direction was always FROM
the generator and TO the resistor (and then converted to heat.) But in
the capacitor, the voltage and current are out of phase, so the energy
flow is back and forth like so:
CAPACITOR
voltage current energy
wave wave wave
. ++++ .
+ +++ +++
++ ++ ++++
+++ + +++
++++ . .
+++ - ---
++ -- ---- VOLTS AND CURRENT ARE 90 DEG
+ --- --- OUT OF PHASE. ENERGY FLOW
. ---- . DIRECTION GOES POS AND NEG,
- --- +++ SO GENERATOR STORES ENERGY IN
-- -- ++++ CAPACITOR, THEN CAPACITOR
--- - +++ DELIVERS ENERGY BACK TO
---- . . GENERATOR AGAIN. EVEN THOUGH
--- + --- VOLTS AND CURRENT ARE THERE,
-- ++ ---- THERE IS NO ENERGY OUTPUT.
- +++ --- ENERGY JUST "SLOSHES" BACK
. ++++ . AND FORTH.
With the resistor, the generator delivered a continuous energy flow. With
the capacitor, the energy sloshes back and forth between the generator and
the capacitor. There is zero average energy flow! The capacitor draws a
current, but it doesn't use any energy. This weird situation occurs when
the voltage and current waves are at 90 degrees phase as my above crude
diagram depicts.
It also occurs when they are at 270 degrees phase, and 270 degrees occurs
when a coil is connected across an AC outlet. (To simplify the concept,
imagine a coil that's wound with special zero-ohm wire.) It seems
counter-intuitive, no? But when you stick a coil of wire across an AC
outlet, the coil draws current, but it draws no energy. Energy goes into
the coil for a moment, but then it goes back to the generator.
What happens at other degrees of phase besides 0,90,180,270? Turns out
that the average energy flow (watts) for pure sine waves can be calculated
like so:
Watts = Volts x Amps x COS(phase)
"phase" is the phase shift in degrees. The cosine function is zero at 90
and 270 degrees, just like the energy flow in the above capacitor diagram.
COS(phase) is called the "power factor". Power Factor causes grief for
free energy experimenters when they try to calculate energy output. If
you calculate watts by multiplying volts and amps, your watts might
actually be much less, or the direction of energy flow might actually be
backwards in relation to what you expect. To calculate the net energy
flow, you must measure the phase difference between volts and amps, then
perform the above calculation.
What about other, non-sinewave waveforms? Easy (though harder to do).
See that capacitor energy wave diagram above? Just take one full cycle
and add up all the pluses and minuses in the energy wave. To do this
accurately you'll have to capture the voltage and current waveforms with
a 12-bit A-to-D card, then do a running total of the product of volts and
amps for one complete cycle. Either that, or buy a (hyper expensive) high
frequency true-RMS AC power meter which has separate inputs for volts and
current.
Needless to say, energy flow measurements are extremely difficult for
anything but pure sine waves. Since most F/E devices rely on nonlinear
physics, their outputs are usually not sine waves. And so it's easy to
make a mistake and fool yourself into believing that your experiment is
producing energy. And unless you normally perform these measurements as
part of your profession, it's difficult to get anyone to believe that you
performed the power measurements correctly.
.....................uuuu / oo \ uuuu........,.............................
William Beaty voice:206-762-3818 bbs:206-789-0775 cserv:71241,3623
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