Daily Parameters of Mobility Scooters
Overload Protection
Overload protection and overcurrent protection are the same, and overloading will inevitably cause current overrun. The mobility scooter manuals all specify the load-bearing capacity, but some cyclists may not pay attention to this, or deliberately overload with the mentality of trying. If there is no such protection function, there is no need to cause damage in any link, but the first thing is the switching power tube. As long as the brushless controller power tube burns out and becomes a two-phase power supply, the old motor becomes weak after running. Pedestrians can immediately feel abnormal pulsation; if they continue to ride, then burn the second and third power tubes. If the two-phase power tube does not work, the motor stops running, and the brushed motor loses its control function. Therefore, overcurrent caused by overload is very dangerous. But as long as there is overcurrent protection, the circuit automatically cuts off the power supply after the load exceeds the limit, and a series of consequences caused by the overload can be avoided.
Overcurrent Protection
It still belongs to the category of over-current protection and is set for a brushless control system that does not have a 0-speed start function.
Speed limit protection is a unique design control program for mobility scooters. When the vehicle speed exceeds a certain predetermined value, the circuit stops supplying power without assistance. For mobility scooters, the vehicle speed is uniformly specified at 20km / h. When designing the vehicle motor, the rated speed has been set and the control circuit has been set. Mobility scooters can only be operated at this speed. The position of the controller does not affect performance, depending on the designer's intention. However, there are several principles:
(1) When the operation permits;
(2) When the overall arrangement permits;
(3) When required by line layout;
(4) When required by supporting facilities.
The output speed signal is a kind of voltage signal. The size of the output voltage depends on the strength of the magnetic field around the Hall element. Rotating the handle changes the strength of the magnetic field around the Hall element, which changes the output voltage of the Hall handle. Then input this voltage into the controller, and then the controller performs PWM pulse width modulation according to the magnitude of this signal. Therefore, the proportion of the power tube on and off is controlled to control the speed of the motor.
