Berger BSS Serie Mode D'emploi page 20

Figure 1-2 Maximum Power Point Curve
In actual application, as shading from cloud, tree and snow, the panel maybe appear Multi-
MPP, but in actually there is only one real Maximum Power Point. As the below Figure 1-3
shows:
Figure 1-3 Mutil-MPP Curve
If the program works improperly after appearing Multi-MPP, the system will not work on
the real max power point, which may waste most solar energy resources and seriously
affect the normal operation of the system. The typical MPPT algorithm, designed by our
company, can track the real MPP quickly and accurately, improve the utilization rate of the
array and avoid the waste of resources.
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BATTERY CHARGING STAGE
The controller has a 3 stages battery charging algorithm (Bulk Charging, Constant Char-
ging and Float Charging) for rapid, effi cient, and safe battery charging.
Figure 1-4 Battery changing stage Curve
Bulk Charging
In this stage, the battery voltage has not yet reached constant voltage (Equalize or Boost
Voltage), the controller operates in constant current mode, delivering its maximum current
to the batteries (MPPT Charging).
Constant Charging
When the battery voltage reaches the constant voltage setpoint, the controller will start
to operate in constant charging mode, this process is no longer MPPT charging, and in the
meantime the charging current will drop gradually, the process is not the MPPT charging.
The Constant Charging has 2 stages, equalize and boost. These two stages are not carried
out constantly in a full charge process to avoid too much gas precipitation or overheating
of battery.
Boost Charging
The Boost stage maintain 2 hours in default, user can adjust the constant time and preset
value of boost voltage according to demand.
The stage is used to prevent heating and excessive battery gassing.
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