Request: Power supply with high isolation volatage

[velislav]

Hi, ALL,

I am looking for a power supply with the following parameters:
V_in 220VAC
V_out 24VDC/5Amax
Isolation voltage 50000V

Any suggestions? (companies, schematics etc)
Thanks in advance.

 

[flatulent]

not standard

50 kV is not a standard isolation for production power supplies(2 kV is more like the isolation limit of mass produced supplies). You will have to make it yourself. I suspect that you will have to use air core transformers and high switching frequencies.

An alternative is to get a mains transformer used to power the lights on AM broadcast station towers. These are about half a meter in diameter. They look like two toroids going through the center air area of the other. This will get you to 220 V isolated on the other side where you can use an ordinary low voltage supply. Put the whole thing in a box which is isolated from everything else by a large distance,

 

[penrico]

Do you mean that is normal to receive 50Kv peaks on your power line?? or you need 50Kv to prevent for lighting??.

If it's only to prevent from lighting, you can protect the input of your power supply using sidactors, PTC, and ceramic dischargers, using it you can clamp the final voltage at input of the power supply to a fixed max value.

Take a look at:

www.crydom.com for sidactors, and ceramic dischargers

 

[velislav]

some details

The power supply is intended for an electronic system, mounted on the roof of electric train. The train is powered with 25kV/16Hz contact wire. In a case of accident, when the wire tears and falls on the train, the equipment inside the train (connected to the a.m. electronic system) and the people touching it, should not be harmed. There is no problem with the information lines - a simple optical connection can be implemented. But it is difficult to find a suitable power supply. BTW, it should be certified.
The system mounted on the roof WILL be damaged, of course. It's case must just withstand about 500A of current for 1 second before starting to melt - the protection automatic needs this time to switch off the power net.

 

[bunalmis]

Use motor and genarotor.
connect the shafts by long plastik shaft.