Regulate 400amp 12 - 16 vdc power supply - Page 1
Forum section: electronics / projects

author: Crambone
author_rank: Frequent Contributor
timestamp: January 08, 2024, 03:33:19 pm
content: I am looking for simple ideas on how to construct a variable for an existing 400 amp 16vdc fixed power supply. I would like ability to adjust from 12 -16 vdc while maintaining 400amps. I’m just sure what would be required? I see some 24vdc 400amp motor controls for golf cart but not sure if that’s an option?Drew

author: coromonadalix
author_rank: Super Contributor
timestamp: January 08, 2024, 04:41:50 pm
content: no because theses motor controller often use PWM signal to control motor, unless you filter out this pwm signaland stabilize it ??or simply try to find Sorensen Xantrex TDK Lambda psuyou need 230vac or 3 phased outlet?but you do realize 400amp at 12-16 vdc is 4-6.5 kilowatt ?? you need an one of a hell "pass transistor" / "mosfet" IGBT something loll

author: edpalmer42
author_rank: Super Contributor
timestamp: January 08, 2024, 05:14:29 pm
content: Quote from: coromonadalix on January 08, 2024, 04:41:50 pmDon't forget the equally impressive heatsink that will be needed to dissipate the 4V @ 400A = 1600W of power!

author: langwadt
author_rank: Super Contributor
timestamp: January 08, 2024, 05:23:13 pm
content: which powersupply?

author: coromonadalix
author_rank: Super Contributor
timestamp: January 08, 2024, 05:43:51 pm
content: Xantrex 6 kw seriesXDC 6000 Watt and 12000 Watt SeriesDigital Programmable DC Power Supply1st digit is voltage, second digits are ampsXDC 10-1200 = 10 vdc at 1200 ampsXDC 20-600XDC 30-400XDC 40-300XDC 60-200XDC 10-600XDC 20-300but you have other series on different makers ... theses are the most efficient and small as you can get, they are smps based / phase controlled etc ... not linearforget about building a simple psu ... unless you try to gobble a car battery charger into a power supply, some of them had variable core on the xformer, but they are very crude supply with low stability, the car battery act as the capacitor, and they are not meant to run continuously, they heat a lot and will bustand normally they are 12-14vdc devices and for sure you can't adjust the voltage down to nothing

author: johansen
author_rank: Super Contributor
timestamp: January 09, 2024, 01:54:49 am
content: Quote from: Crambone on January 08, 2024, 03:33:19 pmThere is a good chance you can simply find the output voltage sense location and its internal reference, and tweak it.No guarantee it will be stable.I have a bc-45 power supply which is a simple 45 amp 13.8v power supply/battery charger, i could easily parallel 10 of them and get your 12 to 16v 400 amp requirement. Its a simple forward converter. I've already repaired one of them when it blew up. The schematic is practically straight out of the uc3844 (iirc) datasheet.

author: coromonadalix
author_rank: Super Contributor
timestamp: January 09, 2024, 04:33:59 am
content: if they dont support load balancing its a no go, the most fragiles of them may blow, since the current will not be shared evenlyyou should use server psu who have load balancing / sharing and normally they talk with each other

author: fourtytwo42
author_rank: Super Contributor
timestamp: January 09, 2024, 07:21:00 pm
content: Quote from: Crambone on January 08, 2024, 03:33:19 pmYou have not mentioned what this psu consists of but if it's just a dumb brick, 50/60Hz transformer, rectifier & filter you could control the INPUT instead of the output

author: johansen
author_rank: Super Contributor
timestamp: January 09, 2024, 07:25:14 pm
content: Quote from: coromonadalix on January 09, 2024, 04:33:59 amDo you know how forward converters work when controlled by a peak current mode topology?Its a battery charger. They dont blow up when you connect them to a dead battery.They can be paralleled indefinitely within reason.

author: coromonadalix
author_rank: Super Contributor
timestamp: January 09, 2024, 07:57:27 pm
content: do it loll you may get some functionality ok if it works for youbut if it is not specified, the weakest ones in parallel may suffer more ...i blew some 1kw server psu with a mere 6 amps, they did not balance properly, and i found some with load balancing, never got any problems ...mileage may vary, good luck