Hi people of the world!
I would like to connect a brushless generator to a solar MPPT battery charger (BlueSolar 100/20 or 100/30). Would it work? It should brake the water wheel and find the optimum power point, but I never tried that, so I don´t know. To the batteries I would connect an inverter, so that I can use AC and draw energy from the batteries. Do I need a DC load on the controller (like for BlueSolar 100/20) or can I put it after the inverter (AC load)?
Thank you!
I've not read up on the topic recently however I did have a friend try this a few years back and struggled with some of victron MPPTs for this purpose. Mainly due to struggling to find the correct configuration/setting within the victron MPPT.
(MPPT's need to be told if they're connect to PV or hydro or wind and he couldnt find that setting)
You're right the logic should be the MPPT would slow the wheel while finding maximum power point however with Solar/PV the calculation can be done quicker because PV reacts faster when a power point is changed. ie when MPPT is searching for maximum power point.
For example
Say MPPT change from power point "x" to "y" while searching for maximum power point.
For PV/solar the actual power output will change quickly when the MPPT changes the power point. So the internal calculation done in MPPT charge controller doesnt need to wait long between changing power point and sensing power output change.
However with hydro it's not quick as you mentioned. So MPPT needs to know to wait/add delay. For hydro when MPPT changes power point you're right the wheel will first slow and then the power output will change which takes a few seconds longer. That's much slower than PV so if not configured correctly the mppt wont wait long enough to see power output change and then will struggle to find maximum power point for hydro/wind systems.
Assuming you're not worried about runaway ie no need for a brake or dump load for the water wheel. Then the below system will work (what my pal did)
My friend has 3 phase micro hydro grenerator plugged into a bridge recitifier to convert to DC. Then he used a Midnite classic charge controller instead of victron mppt as a few years back it had better documentation for wind/hydro than victron.
Then to integrate that into VRM he used a smart shunt as a DC monitor. He needed the additional smart shunt because he also had solar charging the batteries at the same time.
Sorry should also note I've assumed the wheel voltage output is greater than battery voltage (ie enough to charge it with).
