Koyoe KY-EST06KH, User Manual

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5.3 Energy Conversion and Management
The inverter converts the DC power from the PV strings or the battery to the AC power, which
conforms to the grid requirements. It also transmits the DC power from the PV panel to the battery.
The inverter is integrated with a bidirectional converter, which can charge or discharge the battery.
Two string MPP trackers can be utilized to maximize the power from PV strings with different
orientations, tilts, or module structures.
5.4 Power Derating
Power derating is a way to protect the inverter from overload or potential faults. In addition, the
derating function can also be activated by the requirements of the utility grid. Situations requiring
inverter power derating are:
-grid dispatching;
-over-temperature (including ambient temperature and module temperature);
-grid under-voltage;
-export power limit setting;
-power factor.
Grid Dispatching Derating
Adjust the output power according to the remote scheduling instructions and the inverter operates
with the power derating.
Over-temperature Derating
A high ambient temperature or poor ventilation will lead to a power derating of the inverter.
When the internal temperature or module temperature exceeds the upper limit, the inverter will
reduce the power output until the temperature drops within the permissible range.
Grid Under-voltage Derating
When the grid voltage is too low, the inverter will reduce the output power to make sure that the
output current is within the permissible range. The following figure shows the under-voltage
derating curve.