Homebrewed Electricity > Storage
Charging a 24v bank from a 48v bank...or vice versa...how to do it? Can it done?
Warpspeed:
--- Quote from: mab on April 23, 2022, 06:10:54 AM ---I would be very interested in a working version of this cct - but am doubtful i understand enough to achieve it: Obviously one would need a current limiting cct - one that works pulse by pulse - whichever way the current's actually flowing - and an inductor that doesn't saturate within that limit.
--- End quote ---
I have so many partly finished projects on the go here right now, I hardly know which to work on next.
In about another week I plan to order a big batch of circuit boards from China to combine postage cost.
All these circuit boards are required for four quite different projects, and this battery linking circuit is one of those.
Also on order right now are eight 280Ah lithium cells that I will need to finally test the whole thing properly under actual real loaded operating conditions, and I don't expect to receive those cells for at least another eight weeks.
Waiting for the slow boat from China is a frustrating business, but there is no way I can really hurry any of this up.
Not absolutely sure that a current limiting circuit will be necessary, but we shall see. If it does become necessary, it just adds a few extra parts, which would be unfortunate, but not a disaster.
Quite right about the choke being non saturating, and I have had some considerable practical experience designing and testing chokes required for high power pwm inverters. These must be able to handle the quite high surge loads of an inverter, without saturation, so its an important issue to make these inverters truly robust.
I designed and built a high current inductance testing rig that has been successfully duplicated by several other members over at the the Back Shed Forum. With one of those, its possible to safely ramp current up to fifty to eighty amps or more repetitively in a test choke, and watch what the core does as far as magnetic saturation goes on an oscilloscope. Great fun and very instructive.
If a certain core (with a particular air gap) begins to saturate at a measured peak current, the ampere turns to get there will then be known.
Its then easy to work out a suitable tradeoff between inductance and the saturation limit for that particular core, for any number of turns. Several of the guys over at The Back Shed have been duplicating these tests, and we have all learned a very great deal in the process.
So fabricating a suitable non saturating choke for this is not going to be at all difficult. I already have quite a collection of odd chokes here left over from previous experiments, one of which should be well up to the job.
Bossrox:
Yes, I've been using a salvaged tesla 48v powerwall & running it thru a growatt charger to convert it to 24v. Been working great.
Navigation
[0] Message Index
[*] Previous page
Go to full version