Author Topic: building a power supply need suggestions on parts  (Read 2280 times)

0 Members and 1 Guest are viewing this topic.

Online Simon

  • Global Moderator
  • *****
  • Posts: 16644
  • Country: gb
  • Did that just blow up? No? might work after all !!
    • Simon's Electronics
building a power supply need suggestions on parts
« on: November 05, 2010, 04:12:26 pm »
Right, I found a heavy gem at a car boot sale: a 12V 200VA transformer. so I'm planning to use it to build a nice powerful bench power supply with a switch mode regulator.

to ensure I get a good 15V out of it I may well use a doubling rectifier with very large caps but I'm yet to measure the output. I could also do a low voltage  high current output/regulator using a full wave rectifier.

Any suggestions on switchmode regs that can handle 12V 20A and maybe a 5V 40A ?

I'm also looking to make each output current regulated as well so that the max current can be set, now I can do high side current sensing but how do I integrate the current control into the SMPS feedback
 

Offline scrat

  • Frequent Contributor
  • **
  • Posts: 608
  • Country: it
Re: building a power supply need suggestions on parts
« Reply #1 on: November 05, 2010, 05:50:17 pm »
For a voltage source, current feedback control can be an inner loop of the voltage controller.
The voltage regulator generates a current reference, and the current controller generates the duty-cycle.
Both controllers have limited output.
That's what is usually done in variable voltage supplies with variable current limit. They can act as both voltage sources (until the current limit is reached) and current sources (until the voltage reference is reached), following the limit which comes first.
One machine can do the work of fifty ordinary men. No machine can do the work of one extraordinary man. - Elbert Hubbard
 

Offline Murphy

  • Regular Contributor
  • *
  • Posts: 54
Re: building a power supply need suggestions on parts
« Reply #2 on: November 06, 2010, 02:57:12 am »
You're already using a big iron core transformer, what's wrong with linear regulation? Switch mode is so noisy.
 

Offline Mr J

  • Regular Contributor
  • *
  • Posts: 93
    • Facebook mjssvt
Re: building a power supply need suggestions on parts
« Reply #3 on: December 23, 2010, 05:49:03 pm »
I've used a copy of astron's circuit in the past. Cheap, easy, simple. The iron transformer already has a huge loss, go linear :)
 


Share me

Digg  Facebook  SlashDot  Delicious  Technorati  Twitter  Google  Yahoo
Smf