The comical part of this is this was demonstrated by Tesla long, long ago in
'electrical magic' shows whch established him as a wizard. To Tesla's
credit, he recognized the advantages of high frequency and high power. He
was perhaps the first, or among the first, to build high power, high
frequency equipment. Long before vacuum tubes, he used oil-quenched spark
gas as oscillators and built room-sized air core transformers to generate
intense high frequency fields that could excite single-wire light bulbs held
in his hand. He is the true inventor of radio, so recognized by the pathent
department in the '30s.
Mike Carrell
----- Original Message -----
From: "John Fields" <[email protected]>
To: <[email protected]>
Sent: Monday, September 14, 2009 1:27 PM
Subject: Re: [Vo]:The coming of Wireless Power, A report on CNN
Yes, that's the main issue with the harebrained scheme.
How it's done now is that the AC mains are rectified and smoothed, and
then that DC is switched on and off at a high frequency into the primary
of a transformer.
That generates a well-contained magnetic field which builds up and
collapses at the switching frequency, causing a voltage to be induced in
the secondary winding of the transformer, which is then rectified,
smoothed, and regulated as required for the device it's driving.
The thing about the transformer is that the magnetic field is largely
contained within the structure of the transformer and nearly all of the
energy in the primary is transferred to the secondary, with the result
being that a well-designed switching power supply can have an efficiency
surpassing 80%, with some going over 90%
The wireless scheme requires that a magnetic field be generated with a
large loop of wire (the primary of the transformer) and that the
secondary be part of the device being charged/operated, with the energy
transfer occurring when the secondary is in the field created by the
primary.
The fly in the ointment is that there's no way to concentrate the energy
in the field (as is done in the core of the transformer) and couple it
efficiently through air to the secondary in the device being
charged/powered. The result of that is that efficiency of the system
would be _very_ low; I'd guess at 5% or less.
Unfortunately, this little fact (which should be known to anyone with
even a passing interest in power conversion) seems to been overlooked by
the "researchers" trying to foist this huge boondoggle on the public.
Even more disgraceful, in my opinion, is that this "primary" would be on
24/7, wasting a huge amount of power.
On Mon, 14 Sep 2009 07:59:53 -0500, you wrote:
Yet another report on the coming of Wireless power:
http://www.cnn.com/video/#/video/tech/2009/09/13/electricity.without.plugs.c
nn
http://tinyurl.com/rbrpk9
While I love the idea primarily for its convenience I harbor the suspicion
that we are about to unleash the mother of all power vampires across the
national landscape during a critical time in our history when we are trying
to conserve energy. Or is that not the issue?
Comments?
Regards
Steven Vincent Johnson
www.OrionWorks.com
www.zazzle.com/orionworks
________________________________________________________________________
This Email has been scanned for all viruses by Medford Leas I.T. Department.
