Re: Flyback transformer design confusion!!


jasen ha scritto:

On 2006-11-19, elishaphat@xxxxxxxxx <elishaphat@xxxxxxxxx> wrote:


lemonjuice wrote:

As you and any engineer is well aware of
Power = average voltage * average current

Terry Given ha scritto:

ROTFLMAO!

So, for a 50Hz ac power system driving a resistive load:

Vaverage = 0

Iaverage = 0

==> Paverage = 0

by your reasoning. which (given that my electric oven heats things up)
is patently untrue, and is of course (in the case of AC) why we use RMS.

Root mean square is a statistical mean.

no....

if you want to talk statistical measures it's more like the staandard
deviation (and not at all like the mean) infact, where the mean is zero,
it's exactly like the standard deviation.

His
reasoning on this point is intact implying that Vaverage or Vmean, I
averge and P average are not necessarily zero.

with any transformer derived AC and resistive load they will be.

To give you an example your 100W lamp implies that at 240V ac
you have a current of 0.416A. Both the 240V and the 0.416A are rms
values or in other words averages ... square roots of the average of
square values because we working with negative sinusoids.

then they are NOT averages. by definition. RMS = Root Mean Square.

RMS are by definition statiscal averages

Whose definition is this?

I only nknow of 3 types of statistical average,
median,mean, and mode. For (pure) AC median and
mean are 0 and the mode would be the peak voltage.

RMS is not a statstical average.

Yeah. They never teach it to children at junior school but it is an
average .
Check the definition of Wiki for average then compare with this one
here.
http://www.analytictech.com/mb313/rootmean.htm

Not satisfied. Then try a statistics college Professor.



Bye.
Jasen
Cheers

Charles

.

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