Autorecloser and integrated power supply 1

[Uchenna1103]

Please I want to design an integrated power supply for an autorecloser. This power supply will be a part of the recloser itself which means that the use of external distribution power transformer to supply auxiliary power to the recloser will be eliminated but the problem is that I don't know how to extract energy from the medium voltage line without the use of transformer. Please, I will be very glad if somebody can suggest to me how I can get out energy from the MV line without the use of transformer. Please, any technology that can solve this problem will be highly appreciated.

 

[TurbineGen]

What voltage are you connected to? Why not use a transformer? There are plenty that go up to 69kV that will step it down to control voltage.

If that's not an option, how about a UPS? You could run the recloser off of a distribution transformer, through the UPS. When the power is cut, the UPS will provide power for some amount of time depending on size and power requirements.

Or perhaps I do not understand the question...

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If it is broken, fix it. If it isn't broken, I'll soon fix that.

 

[davidbeach]

Or, just buy one off the shelf.

 

[jraef]

You can get all the power you want from the MV line without a transformer (within the limits of what's available). The only problem is, it will be at the same potential as the line! The main purpose of the transformer is to step the line voltage down to usable voltages.

"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
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[Uchenna1103]

Hi,

Thanks for the response so far. I am working on 15kV distribution line. The recloser is expected to get its primary auxiliary voltage from the distribution line without the use of a transformer. Therefore, I am actually looking at how I can get 120V usable voltage from the distribution line without the use of transformer. Please, is there any technology or small device that can help me achieve this aim? Thanks for your assistance.

 

[davidbeach]

Why not just buy one that already exists? No need to invent your own auto recloser.

 

[DTR2011]

capacitive voltage divider....inspect a cvt.

resistive voltage divider.

hint....tear apart your cell phone charger

 

[HornTootinEE]

You could get a hydraulic recloser. They don't use 120V, they operate on line potential for closing power and they trip on current. That would solve your problem. Electronic controlled reclosers require 120V from some source, so other than alternate methods as smallgreek suggests I'd say you're stuck with a distribution transformer. A small one, 3 kVA will do the job.