An electric hub motor is incorporated with the wheel hub so it can drive directly. It is also known as wheel hub drive, wheel hub motor, wheel motor, and in-wheel motor. It is mainly used in electric bikes to control the speed movement of the bike. The most used type of motor is the Brushless DC motor; though expensive, they are long-lasting.
Functions of electric hub motors.
There are different ways the hub motor is used. Here are some of its uses.
Cooling of the motor
There are two ways of cooling the hub motor: the water and air cooling methods. Water cooling is whereby a special cooling fluid channel during the heat exchanger, the wheel hub, is cooled using the liquid.
Braking system integration
Wheel motors are used in brake systems which include friction and braking systems. The integration of the friction brake system is generally using a disc brake. The friction clamps the disc brake from both sides, thus generating brakes.
Braking energy recovery
During the braking process of an electric bike or vehicle is the transmission of the kinetic energy of the whole vehicle to the motor through the wheels, thus driving the hub motor to rotate. At the same time, the motor works as a generator and charges the energy storage devices, the supercapacitor, or the battery. The motor converts the braking energy into electrical energy, stores it in the battery or the supercapacitor, and realizes utilization and energy regeneration.
Bearing and driving
Driving and carrying is a must for the wheel motor. For the axle bearing to realize the stator’s centering rotation, the load-bearing must rely on the axle bearing. The suspension axle housing is connected to the wheel rim of the whole vehicle through the axle bearing. It uses axle bearing instead of stator and rotors to carry the load and the road shock absorbers. The outer rotor is connected to the wheel rim to achieve the purpose of driving directions.
Electronic differential speed control
The front wheel steering is the realization method that is achieved by an ordinary steering gear. The electronic differential completes the rear wheel needs a slip, the front wheel steering angle is solely determined by the turning radius and the car turning radius and the rear wheel slip determines wheelbase. To get the rear wheel slip is also calculated from the rotation angle of the steering gear of the front wheel. When the rear wheel can’t differentiate if it is electronic or not, the inner wheels should be changed from active to slave. It can be achieved by disconnecting the hub motor or connecting the resistor in a series of loops
When it comes to using the electric hub motor it can be used to cool the motor, bearing and driving, brake integration and it is mainly used in electric wheels and vehicles to control their speed and movement.