Continue to Site

Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

72V regulated power supply

Status
Not open for further replies.

yshimizu

Newbie level 3
Joined
Mar 14, 2012
Messages
3
Helped
0
Reputation
0
Reaction score
0
Trophy points
1,281
Activity points
1,312
Hi friends,

I am trying to construct a 500W Power supply for a massive LED that I have.
The specs of the circuit are:
P = 500W
Iout > 7.8A
Vout = 72V±2V
Vin = 120V 60 & 50Hz AC (USA and Japan wall socket)

I am currently looking at a couple of solutions.
1. Buy 2 of these and hook them up in serial **broken link removed**
2. Variac -> bridge rectifier -> massive capacitors -> current control resistor -> LED

The reason I am looking at a Variac is because it seems to be cheaper to get a variac than an actual transformer. And maybe i am looking in the wrong parts of the internet but I am having trouble finding transformers that match my requirements. I am open to other creative solutions too, I just want to run this thing as cheap as I can. I asked a power circuits professor that I know and he suggested looking up a couple of Dc-Dc converters up and examining their schematic. I'm sure he has some good advice but from what I see here you guys are pretty good with stuff like this too. Also please let me know if there are problems with my two suggestions.

Cheers
 

Dear yshimizu
Hi
I think you can design it with yourself and some helps ( it is really simple ).
Best Wishes
Goldsmith
 

P = 500W
Iout > 7.8A
Vout = 72V±2V
Vin = 120V 60 & 50Hz AC (USA and Japan wall socket)

I am currently looking at a couple of solutions.
1. Buy 2 of these and hook them up in serial **broken link removed**
2. Variac -> bridge rectifier -> massive capacitors -> current control resistor -> LED

I think two 36V smps units will perform much better than a variac+bridge+cap+resistor.

If you are talking about chains of LEDs connected in series/parallel then they are voltage dependant.
A variac will produce semi-fixed output voltage only when the input voltage is stable and any variation in the input voltage will ruin the output voltage stability, whereas 2 (36V) regulated switching power supplies will output nice 72V ..

:wink:
IanP
 

That FSFR2100 is interesting. but i need slightly more power than that, does that mean i can connect two of these in parallel to handle more current?
The two power supplies is also super attractive because i can get it for 80dollars total. I'm only willing to look into constructing my own circuit if it is more effective or costs less than that.
 

A variac+rectifier would work okay, but IanP said, it will be unregulated. A good solution would be to use a simple discrete current regulator on the DC output. A current regulator is probably a good idea even if you go with a regulated voltage source.

I'd advise against fancy PWM controllers like the FSFR2100, unless you already are familiar with LLC resonant converters and are capable of making the necessary transformer (most people can't do that).

If you have the parts on hand for doing the variac+rectifier+regulator, I would give that a shot. If you don't, and have to spend some money in either case, I would just buy the supplies.
 

hmm it seems like just buying two of those power supplies is the best way to go. From my understanding as long as you don't exceed the current ratings for the power supplies you are safe correct? I don't really know the specifics on how connecting these power supplies serially could potentially cause a problem, maybe someone can inform me on that. Do you guys recommend still using a current regulator (current mirror?) even with these regulated power supplies?
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Back
Top