High Voltage DC Power Supply (0-900 VDC)

[LiveRock]

Hi

I need to build a simple High voltage DC Power supply for my laser.

Specs:
Input: either 9-12 VDC or 240 VAC

Output: 0-900VDC

Possible solutions include using flyback, etc.

Any ideas?

My Projects:
http://www.hotsource.net/projects/main.php?cmd=album&var2=1

 

[LiveRock]

I found

http://www.electronics-lab.com/forum/index.php?topic=6517.0

Got questions:
(a) How do I vary the output from 0-900V?
(b) Will  the transformer 'die' if the secondary is open?
© Assuming I am using a input voltage of 0-12 V, what will be the transformer rating?
Say, primary 12V, secondary 900V
Will a 3V to 240V transformer work?
If it does, does a 3v to 240V transformer handle 900V? Or must I get exact rating of 12V to 900V transformer?

Thanks and hope to hear from the experts!! Cheers!

 

[ZomBiE]

You're on right tracks. You should start by checking wattage that laser of yours needs, 0-900 is not neccessary. but say 100-900 would do. Transformer where output voltage rises when open, 900v is target, would easily rise above 1200v and that might create an arc between windings. I used super-glue to create extra isolation when i tried such high-voltage projects for CCFL lamps that required 800-1250v operating. but wattage needed on output is most significant in this case. If you need a 100W toroid transformer, it wont work. Toroids in general doesn't have good enough isolation for this. PCB encapsulated transformers would be the best choice because those have quite good isolation voltage, about 5000v winding-winding.

 

[LiveRock]

Thanks, Zombie.

Actually, I need the 800-900 VDC to charge capacitor, the energy will be release to a flashlamp in a instant that will lase a YAG Laser.

Using a flyback transformer will yield too much voltage, right?
how does a PCB encapsulated transformer look like? Is it a 'normal' squarish transformer with a metal core?

 

[LiveRock]

I did a search and encap transformers look like:

http://www.dagnall.co.uk/frame.asp?src=products.asp