TS-MPPT-600V-48 Wind charging control Info

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Figure 4: TriStar-MPPT (150V) Input Voltage vs. Battery current Derating
What are the maximum operating power levels for the TriStar MPPT controllers? The max. output charging power of
the controllers is proportional to the battery voltage based on the maximum rated output current.
Max. Charging Power (max. Wb) = Rated Output Current (max. Ib) X Battery Voltage (Vb)
Therefore, the lowest max. charging power for the controller when there is no derating is based on the minimum
possible battery voltage during max. charging current operation (60A, 45A or 30A). Most battery based systems may
have a low voltage disconnect (LVD) of 11.5V, 23V, 46V for a 12V, 24, 48V nominal voltages. However, battery
voltages increase with high charging current. The minimum battery voltage during the full rated charging will depend
on the battery size, maximum load and other factors. However, typically the minimum battery voltage should never
be lower than the nominal voltage of the system (12V, 24V or 48V) when the controller is operating at the rated
charging current.
The battery charging power (Wb) = Input Power (Win) X Efficiency
Therefore, Win = Wb/Efficiency
This information can be used to determine the amount of power that the TriStar MPPT controllers can reliably
process with wind and hydro turbines.
Example:
Max. Ib = 60A
Vb min. during charging = 48V
Wb max. at Vb min. = 60A X 48V = 2880W
Max Efficiency at Full Power = 96%
Win = 2880/.96 = 3000W
It should be reasonable to expect the 60A TriStar MPPT controller to handle at least 3000 Watts of power from a
turbine for a 48V nominal system. There may be other factors in the system that can affect the minimum voltage