On Mar 26, 9:35*pm, Cecil Moore wrote:
Keith Dysart wrote:
Or perhaps the element you have identified does not have
the appropriate energy flow function? (It doesn't.)

Please prove your assertion.

So you are having difficulty doing the math to justify
your hypothesis.

This requires that the sum of the flows out of the
elements providing energy equals the sum of the flows
into the elements receiving the energy.

True for energy. Not true for power.

Ummmmm. Conservation of energy requires that the total
quantity of energy in the system not change. This requires
that the sum of the changes of the quantity of energy in
each element be zero. A change in energy quantity is a
flow. The energy flows must sum to zero. Energy flow is
power. The powers must sum to 0 to satisfy conservation
of energy.

And we are still waiting for the energy flow function
for the element that you claim is doing the storing
of the energy.

If you cannot understand the reference I gave you,
I don't know what to tell you.

You could simply do the derivation for an example that
demonstrates your hypothesis.

Does it detect energy? Are you sure?
Or is it voltage that it detects? Or current?

Please provide proof that voltage or current can
exist without energy.

I realize now that you were probably thinking of a TDR
that sent a pulse (I was thinking of one that sent a
step). My assertion is that when
Ptotal = Pfor - Pref
the idea that Pfor and Pref describe actual energy
flows is very dubious. Ptotal always describes an
energy flow.

When Pfor is 0, then Pref is equal to Ptotal and since
Ptotal is always describing an energy flow, Pref does
in this case as well. Similarly when Pref is 0.

-------

And now, since you are having trouble computing the
energy flows into the various elements here they are
again, for the circuit in the example of Fig 1-1, 100 Vrms
sinusoidal source, 50 ohm source resistor, 45 degrees of
50 ohm line, 12.5 ohm load, after the reflection returns...

The power flow into the line is
Pg(t) = 32 + 68cos(2wt)
and along with
Ps(t) = 100 + 116.6190379cos(2wt-30.96375653)
Prs(t) = 68 + 68cos(2wt-61.92751306)
energy is nicely conserved because
Ps(t) = Prs(t) + Pg(t)

The load presented by the line has a resistive and a
reactive component, so we can separate the power into
two parts
Pg.resis(t) = 32 + 32cos(2wt-61.92751306)
Pg.react(t) = 0 + 60cos(2wt+28.07248694)
which, for confirmation, nicely sums to Pg(t) above.

Now as I recall, your claim was that the total power
dissipated in the source resistor would be the power
dissipated before the reflection returned plus the
power imputed to be in the reflected wave plus the
power stored in and returned from some other element
in the circuit.
Prs(t) = 50 + 50cos(2wt)
+ Pr.g(t)
+ Pstorage
= 50 + 50cos(2wt)
+ 18 - 18cos(2wt)
+ Pstorage
Pstorage = 68 + 68cos(2wt-61.92751306)
- 50 - 50cos(2wt)
- 18 + 18cos(2wt)
= 0 + 36cos(2wt-90)
which is not the power function of the reactive
component of the line input impedance, Pg.reac(t),
computed above. So the energy is not being stored
in the reactive component of the line input
impedance.

...Keith