electrical power through satellite

1) Is it possible to send electrical power through satellite. please send ur answers 2) why the india is not go for 60Hz transmission.
Reply to
raghu
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Define what you mean by "electrical power". Most satellites pass power from the Sun down to earth.

No; post here, read here.

Because most of the world went for 50Hz transmission.

Reply to
Andrew Gabriel

I recall discussions at times about beaming power via satellites, perhaps using lasers.

There have been studies of putting up huge solar "farms" and beaming the power back to earth. I think a search of the web will find discussions on those studies.

I can't see it ever coming into even a test phase. Just imagine what happens to the beam back to earth if they lose pointing!! Burn a track through a city or some such thing.

I shouldn't say it can't be done because sure as hell someone will come up with a method of doing it safely.

Reply to
Rich256

Yes. Without electricity running through them to power their gadgets, they would be of little use.

Reply to
JohnR66

Cos most of the developed world uses 50hz, so why change?

Ses Pit.

Reply to
SesP

USA has 60HZ supply!!!

Reply to
Pork Cheese

exactly, read above statement...

Pit.

Reply to
SesP

Despite the parochial blinkered view of a lot of Americans and despite the fact they are the biggest economy . There is actually 95% of the world population outside the USA.

Reply to
John G

yes indeed, power in the form of data including audio and video signals travel through satellites all the time except when someone interferes with them by 'downloading power from the ionosphere' :)

apparently India just isn't up to speed :)

Reply to
TimPerry

Before everyone gets into a pointless trans-oceanic war about this, it might be more accurate to point out that India is a former colony of the UK. Most, if not all of the former colonies followed the mother country when it came to electrification of their countries.

This is especially true of France as her many former colonies in Africa followed the practice in metropolitan France... One comes across one or more large 220-240V transformers feeding the entire village with thick secondary conductors, 3-phase being the standard.

Prior to the 1930's in the USA, there were many different standards for power voltages and frequencies (particularly in small towns). The interconnection of grids from the turn-of-the-century forced the dominant 60 Hz practice to become the standard. 60 Hz has the advantage over 50 Hz in that incandescent lamp flicker is almost completely not visible at the higher frequency (when low wattage lamps are observed). 50 Hz has the advantage of less inductive reactance for motors and (power transmission) transformers.

During the depression era of the 1930's, the REA - Rural Electrification Agency (a division of the Department of the Interior) looked at all systems in use (including the European 3-phase 240V 50 Hz systems) and decided that the most efficient and economical model was the Edison 3-wire split (single) phase system that offered 110/220 to most households. It was determined that American farmers would not be handicapped by limiting most household wiring to single phase because single-phase repulsion start - induction run motors were readily available in sizes over 10 HP to do the heavy duty chores around the farm.

Thus, this became the defacto standard for residential service in the USA... The point being that the Euro 240V/50Hz systems are not necessarily inherently superior.

Beachcomber

Reply to
Beachcomber

I never said that either system was superior and in fact there are merits on both sides. All I said was that about 5% of the world is 60Hz and 95 % is 50Hz.

Your reasons for this split are somewhere near the truth except the US decision was more likely all about the money needed to change from the primitive Edison system which was too entrenched by the 1930s.

Reply to
John G

I think this is the type of system he was thinking about:

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Reply to
Rich256

if migrating spotted owls or airplanes flew thorough the laser beam they would die!

a rain cloud moving through would diffuse the beam.

why not just use Tesla coils?

get 3 of them and run them in 3 phase !

Reply to
TimPerry

Although the Edison system was well established before the '30's as you indicate and the cost of changeover was high, it is not "primitive" and has some advantages for a dual voltage system where loads do not justify a polyphase system. Certainly it was recognised as being adequate for most farms of the time but it had already been considered adequate for most urban homes and small business's so the incentive to stay with what was available (and equipment designed for) was obvious even to beaurocrats.

However, in the 30's and 40's the typical electrified farm had a 3KVA transformer (sometimes 5KVA) which was fed from a single phase feeder. The idea of a 10HP single phase induction motor simply didn't come up in most cases (and such a motor is uncommon and expensive even now) and a 1 or 2 HP motor was considered large. The farms were far enough apart and loads light enough that the distribution lines only carried one phase and a neutral (sometimes eliminating the latter and using ground return). To do otherwise was too costly.

Don Kelly @shawcross.ca remove the X to answer

Reply to
Don Kelly

I guess I agree with most of that but loads have got larger with 40hp irrigation pumps not uncommon in Australia.

We also have some SWER (single wire Earth Return) to farms that do not need any more.

If we started this disscusion in either the Metal or Wood working news groups there would be a flurry of Americans wishing they could get 3 phase to domestic premises to run their machinery.

It 's easy in most 50hz countries where 3 phase is often put on for anything bigger than a window airconditioner. In our mild climate lots of houses do not have any A/C and minimal heating. I have a 3 phase reverse cycle A/C.

Reply to
John G

raghu schrieb:

Hello,

Japan was very flexible. One part uses 50 Hz, the other part 60 Hz. The manufacturers of electric appliances should build units which could be used on both frequencies. Easy to sell them in the whole world.

Bye

Reply to
Uwe Hercksen

It's also 100Vac instead of 110-120 Vac. I used to know the reason but I've forgotten now except that it had to do with a communist origin.

Reply to
Pop

Japan has AC-DC-AC converter stations to link (+ $$) the two sides. The mixed frequency was a historical accident- not a "thought out" choice based on engineering or economic reasons. Brits sold in one area and Yanks in another. The problem is with the most common motors- induction motors. This brings in frequency related problems. One of the major ones is that a 4 pole 60Hz motor runs near 1800 rpm while its 50Hz equivalent runs at near 1500 rpm. This can affect mechanical loads. A 50Hz motor running at 60Hz will be fine except for some reduction in starting current and torque (at a given voltage) (nearly 5/6 and 25/36 as a worst case estimate and a 60Hz motor will need a voltage at 50 Hz which is 5/6 of the 60Hz motor. These are ball park estimates. Tradeoffs occur in design. Spend more money and you get your wish- something which is not optimal at any frequency or somethng requiring a special frequency converter. The problem is not as big as you think because common motors are readily and economically available for either frequency and "portability" is not generally an issue.

Reply to
Don Kelly

Ah, yes, 100V ?? US style plugs, and former USSR is 220V with different plugs. It seems that Japan is on its own as far as nominal voltage, and having never been communist, I fail to see the reasoning. Is the hot wire red? Please clarify.

Reply to
Don Kelly

Being one of the worlds most technologically advanced societies, why has Japan not begun a conversion initiative to go one way or another on the 50 vs. 60 Hz infrastructure? Is it just a matter of being cost prohibitive?

And does anyone know the real story on why 100V was picked, that being a non-standard voltage with the entire world?

Beachcomber

Reply to
Beachcomber

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