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How "clean" does the PV input DC need to be on a MPP Inverter?

Malmen

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I want to use a cheap chinese generator as a backup to be able to charge my battery bank during bad weather. Problem is the generator AC output is not very clean so I don't want to hook it to the AC input. What if I rectify it to DC and run it into the PV input on my MPP Inverter to fake solar PV production? Question is how picky is my MPP Solar inverter (GIK3024) on the PV input? DC voltage will be rectified 230V AC (Europe) to approx 320 V DC. This should work fine in theory right? Max PV voltage is 500 volt and MPPT works between 120-450 volt acording to manual. Any downsides doing it like this?
 
I want to use a cheap chinese generator as a backup to be able to charge my battery bank during bad weather. Problem is the generator AC output is not very clean so I don't want to hook it to the AC input. What if I rectify it to DC and run it into the PV input on my MPP Inverter to fake solar PV production? Question is how picky is my MPP Solar inverter (GIK3024) on the PV input? DC voltage will be rectified 230V AC (Europe) to approx 320 V DC. This should work fine in theory right? Max PV voltage is 500 volt and MPPT works between 120-450 volt acording to manual. Any downsides doing it like this?
Mppt solar controllers expect a current source not a voltage source. So the danger is the mppt will overload the generator while trying to find the max power point.
 
I see, but won't it accept the voltage provided if it can draw the full power from PV input? Will it still hunt around for MPPT?
 
I see, but won't it accept the voltage provided if it can draw the full power from PV input? Will it still hunt around for MPPT?
Did you make any progress by now? Or anyone reading this thread for that matter
 
I'm contemplating similar.

First concern would be soft start; capacitors would look like a dead short, and generator would deliver high current.

So long as MPPT doesn't draw voltage down to the point of excessive current, should sit at high voltage full power.
Some MPPT have a "turbine" mode for wind/hydro.

Some people have successfully fed EV HV battery into PV input of an inverter. That would be even stiffer than a generator.
 
“ I want to use a cheap chinese generator as a backup“ …….👀
 
Current practice is to use a chargeverter to clean up output of generator to directly charge 48v battery.

Consider MPPT if you have high voltage DC like from a hybrid car.
 
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