Sun21 MAX-M2024, Руководство пользователя

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solar charge controller with Maximum Power Point Tracking (MPPT) Technology can
lock on the point to harvest the maximum energy and deliver it to the battery.
The MPPT algorithm of our company continuously compares and adjusts the
operating points to attempt to locate the maximum power point of the array. The
tracking process is fully automatic and does not need user adjustment.
As the Figure 1-2, the curve is also the characteristic curve of the array, the MPPT
technology will
‘boost’ the battery charge current through tracking the MPP. Assuming
100% conversion efficiency of the solar system, in that way, the following formula is
established:
Input power (P
PV
)= Output power (P
Bat
)
Input voltage (V
Mpp
) *input current (I
PV
) =Battery voltage (V
Bat
) *battery current (I
Bat
)
Normally, the V
Mpp
is always higher than V
Bat
, Due to the principle of conservation of
energy, the I
Bat
is always higher than I
PV
. The greater the discrepancy between V
Mpp
&V
Bat,
the greater the discrepancy between I
PV
& I
Bat
. The greater the discrepancy
between array and battery, the bigger reduction of the conversion efficiency of the
system, thus the controller’s conversion efficiency is particularly important in the PV
system.
Figure 1-2 is the maximum power point curve, the shaded area is charging range of
traditional solar charge controller (PWM Charging Mode), it can obviously diagnose
that the MPPT mode can improve the usage of the solar energy resource. According
to our test, the MPPT controller can raise 20%-30% efficiency compared to the PWM
controller. (Value may be fluctuant due to the influence of the ambient circumstance
and energy loss.)
Figure 1-2 Maximum Power Point Curve
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