Just wondering, is there a way for an MPPT algorithm to estimate the amount of uncollected PV power at any point in time?
example: system is in absorb and has not yet achieved end amps. The battery is absorbing 3amps at 60 volts (180 watts). The PV array is in sun and could be producing 3000 watts. That leaves approx 2800 watts uncollected.
Could that 2800 watts be estimated and trigger additional loads?
(I do lay awake at night)
Use a load via aux 2 utilizing Waste Not and all the available power above Absorb and Float will be used.
Larry
More stuff I do not know. Tell me if I have something wrong.
The Max Power Point is determined by several things:
1 Available sun
2 angle of incidence
3 Temperature
4 Panel specifications
5 Load
The MPP will "move" with any changes to the above.
If one were to look at a 30 second time frame,items 2, 3, & 4 are constant.
Item 1 should be relatively constant in this short time frame.
Therefore variations in the load would be the only thing "moving" the MPP.
My possibly irrational assumption is the MPP will move less with higher available Sunlight.
Could the delta MPP per delta load be used to extrapolate available power?
This could inform as to when an additional load could be introduced.
( this really is fun but I need a nap)
I would place temperature on top.
Partial shading would be 2nd on the list or actually right up there with temperature IF there is any partial shading of the array
boB
Quote from: Barry Fields on February 08, 2024, 02:15:46 PMItem 1 should be relatively constant in this short time frame.
Therefore variations in the load would be the only thing "moving" the MPP.
My possibly irrational assumption is the MPP will move less with higher available Sunlight.
Could the delta MPP per delta load be used to extrapolate available power?
In a 30 second time frame, could the above be true?
The load changing should not move the Vmp as long as the controller and PV array is supplying all it can to charge the battery and any external (inverter) loads.
Vmp changes with the things on your list.
Except for cloud movements or shading, 30 second intervals should pretty much stay the same. Sunlight or insolation will affect the Vmp slightly though. But temperature, being one of the main things that change Vmp, is also slow-ish to change a lot I think during a 30 second time frame.
boB
What I hear you saying is:
Assuming over a 30 second time frame and all variables being constant except Sunlight and load, the movement of MPP versus load would be too small to extrapolate available power.
Not to be obstreperous but is the above known to be true?
I am asking these questions because I feel one of the largest issues with efficient solar collection is Load Management. Just looking for that better mouse trap.
Thanks for your time.