I'm working from a while ago on a DC-UPS concept, after I've put all the things together and I'm requesting from you an advice, can I start to build it or I have serious flaws in it ?
- Current comes from AC-DC transformer at 27.6V, goes into a distribution box like the one in this image
- Current goes to battery-distribution box which is wired on negative terminal with a resistor (limit charging current) and a diode in order to block current flowing OUT of the battery + blocking current flow other way around (thru load distribution box) - if grid power is available and the transformer works current on this state could only flow INTO the battery and not OUT of it. Due to Schottky diode there is a voltage drop of max 0.55v - so the battery won't charge higher than (27.6v - 0.55v) = 27.05V
- Current also goes to load-distribution box in order to feed the load with power
- From battery distribution box perspective, if AC-DC transformer stops delivering current (grid is down) it will feed the load distribution box making it a fully functional UPS with zero delay.
- Due to Schottky diode connected from battery distribution box to load distribution box there is a voltage drop of 1.1V - the battery won't reach a higher voltage than 27.05v so the load voltage (on battery power) will be somewhere between 25.95V (fully charged state) and 21.9V (near fully discharged)
- From LOAD distribution box perspective, there are two voltages present > the battery (25.95V fully charged - 21.9 near depletion) AND 27.6V (if there is grid power available) so the load will be feed from AC-DC transformer at 27.6V when everything works in order OR 25.95V from battery when the grid drops out.
I'm not 100% positive that I've put the diodes on the right places, electrons flow from battery negative > positive / from PSU should be the same. If the battery discharges when negative electrons are attracted by positive terminal then charging is made by feeding electrons to the negative end ?
I'm willing to create an efficient circuit in order to keep a strip of LED's running all the time 24/7 - total load of the circuit is somewhere around 3Kw (yes, I know that the AC-DC transformer is too small for the job but currently I'm thinking about it upto ~ 800W)
(sorry for my bad english)