niu Kick Scooter KQi3 Service Manual page 37

FOC Controller
Main protective functions
1. Current limit protection
The maximum controller output current is limited to protect the motor, controller, battery
and other components from being damaged by a current greater than specified.
2. Rotation failure (overload) protection
The controller judges the motor status automatically in a certain period of time after the
motor rotation failure (over-current) occurs. It controls automatically the output current to
protect safety of the motor, controller and battery.
3. Under-voltage/over-voltage protection
The controller stops automatically the motor rotation when the input voltage to motor is
lower or higher than the set value, in order to protect safety of the motor and extend the
battery lifetime.
4. Power cut-off protection in charging or braking
The controller stops the motor automatically to avoid unexpected injuries when the vehicle is
being braked or charged.
5. Control loss protection
The controller stops the motor automatically to avoid unexpected injuries when the Hall
cable sensor or its circuit fails and is out of control. The functions such as motor temperature
protection, controller temperature protection and motor winding short protection are also
provided.
V1.0.0
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