MPPT Solar Charger Design
MPPT Solar Charger Design
(OP)
I am designing a MPPT solar charge controller (buck mode) to charge batteries from 500 Watt solar panel. As per my calculations i need 50uH inductor with current rating of 50A for 12V battery.
My problem here is getting an inductor for 50A rating as it will be big and bulky.
The solution i plan to use is divide the buck circuit into 4 sub-circuit with 4 individual inductor rated for 12.5A.
And finally parallel the output.
But some people suggested that it might cause uneven loading of power and might result in uneven heating of mosfet.
I need some advice in this part, as to whether the idea of sub-circuits will work or do i need to take some precautions during the design.
Thanks
Regards
Gokkul
RE: MPPT Solar Charger Design
http://www.ebay.com/itm/LCD-display-50A-Solar-Char...
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RE: MPPT Solar Charger Design
@IRstuff
Thanks for pointing that out :). But this is a design that a friend of mine plans to manufacture, so i need to get the design done.
Thanks
Regards
Gokkul
RE: MPPT Solar Charger Design
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RE: MPPT Solar Charger Design
If nothing works out i guess i will have to reverse engineer someone else design.
Thanks
Regards
Gokkul
RE: MPPT Solar Charger Design
Another option would be to buy several pre-made buck-mode boards of around 12 Amps each to check out your concept to quickly make sure it will work. A quick check at Linear Tech showed they had a LTC3867 demo design with a 38V max input and 14V output. NOTE - The LTC3867 demo is just the quickest and first thing I found. I'm not saying base your final design on whatever chip is used on the demo board, just first use the demo boards to check your concept or approach to the problem.
RE: MPPT Solar Charger Design
RE: MPPT Solar Charger Design
Thanks
Regards
Gokkul
RE: MPPT Solar Charger Design
Mike Halloran
Pembroke Pines, FL, USA
RE: MPPT Solar Charger Design
Note sure what they're talking about. Just do your calcs.
RE: MPPT Solar Charger Design
When you mean 3 legged you mean that you used 3 buck converter in interleaved pattern, so current on each inductor is approx 33A ?
Keep them separate means individual inductors on individual core right? What does "not physically lined up" mean?
Will keep in mind all the mentioned points.
I am currently planning to implement interleaved converter design with separate driver circuit, mosfet and inductor.
Thanks
Regards
Gokkul
RE: MPPT Solar Charger Design
Not physically lined up literally means not positioned directly side-by-side. If possible, put them at right angles to each other, or physically separate them. Otherwise any magnetic flux not contained within the core can be coupled into the neighbouring core and give you undesirable results.
RE: MPPT Solar Charger Design
Ahh nice tip, thanks :).
Thanks
Regards
Gokkul
RE: MPPT Solar Charger Design
http://en.wikipedia.org/wiki/Cuk_converter
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