Hub Motors

After the hub motor is energized, the motor converts electrical energy into mechanical energy, thereby driving the wheels to rotate and driving the vehicle forward. In wheel hub motors are widely used by electric vehicles due to their professional design and low prices.

There are two types of BLDC hub motors sold online by ATO: Gear hub motors and gearless hub motors. When the electric vehicle is powered off or the battery is dead, there is a clutch device designed inside the gear hub motor, which makes the resistance of the vehicle sliding or pedaling by humans smaller than the resistance of the gearless hub motor under the same conditions, so the gear hub motor is widely used by electric vehicle manufacturers.

With the development of technology, the production of ATO BLDC hub motors is very sophisticated, and there is no need to worry about friction, noise and wear due to insufficient precision. The internal structure of the gearless hub motor is relatively traditional. Generally, there is no clutch device inside. Electric hub motor directly relies on electromagnetic conversion to generate mechanical energy to drive the electric vehicle. Therefore, it is necessary to overcome the electromagnetic resistance when riding the power off.

It is strongly recommended that you buy ATO brushless electric hub motors, because we have a wealth of models for you to choose: The power options are 250W, 350W, 500W, 750W, 1000W, 3000W. The voltage options are 24V, 36V, 48V, 60V, 72V. The maximum torque is up to 95 N.m. Contact us to make a purchase now.

Hub Motor Working Principle

The working principle of a hub motor is an electronic phase changer (switching circuit). According to the position sensor signal, the electric hub motor controls the sequence and time of energizing the stator winding to generate the rotating magnetic field and drive the rotor to rotate.

The electric vehicle wheel hub motor assembly and control system belong to the automotive parts, which is the key core component of electric vehicle parts.

The system is characterized by the unique design of the motor system, brake system and suspension system in one, with permanent magnet brushless synchronous electric vehicle hub motor and switched reluctance hub motor, which can be controlled by PWM and AC frequency control. This BLDC hub motor design has the features of high efficiency, lightweight, long life, low noise, strong matching, simple structure, easy assembly, complete function, independent suspension, safety and reliability, without axle, transmission and other mechanical parts and directly hanging on the body to install tires, transmission consumption is equal to zero, and rotation efficiency is 100 percent.

Types of Hub Motor

Gear Hub Motor

Geared hub motors, on the other hand, have their cases connected to the stator through a planetary gear reduction system. For every rotation of the case, the motor inside actually turns many times faster. This allows the motor to work at higher and more efficient speeds, while still allowing the wheel to spin at a comparatively slower driving speed.

Geared Hub Motor Pros

• More torque
• Little drag
• Smaller
• Lighter
• Durable

Gearless Hub Motor

Gearless hub motors (gearless hub motors are also called "direct drive" hub motors), in a direct drive hub motor, the axle that passes through the center of the motor is actually the axle of the motor itself, with the copper windings fixed to the axle. This whole axle assembly is called the "stator". The magnets are mounted to the outer shell of the hub motor. When electricity is applied to the stator a magnetic field is induced that causes the magnets to move.

Gealess Hub Motor Pros

• Fast
• Quiet
• Durable

Structures of Hub Motor

1. Stator core
The stator core is part of the hub motor magnetic circuit, and on which the stator winding is placed. In wheel hub motor is generally made of 0.35~0.5mm thick silicon steel sheet with an insulating layer on the surface, laminated, and evenly distributed slots are punched in the inner circle of the core to embed the stator winding.

2. Stator winding
The stator winding is the circuit part of the hub motor, which is connected to the three-phase alternating current to produce the rotating magnetic field. BLDC hub motor is connected by three identical windings with the same structure, which are spatially separated by 120°electric angle and arranged in a team. The coils of these windings are embedded in each slot of the stator according to a certain rule to ensure reliable insulation between the conductive parts of the winding and the core and between the winding itself.

3. Machine base
The base is usually cast iron, and the base of a large asynchronous motor is generally welded with steel plate, and the base of the micromotor is made of cast aluminum, which fixes the stator core and the front and rear end cover to support the rotor, and plays the role of protection and heat dissipation. The enclosed motor has heat dissipation bars outside the base to increase the heat dissipation area, and the protective motor has ventilation holes on both end caps to enable direct convection of air inside and outside the motor to facilitate heat dissipation.

4. Rotor core
The rotor core of the three-phase asynchronous motor is used as part of the magnetic circuit of the hub motor and the rotor winding is placed in the core slot, and the material used is the same as the stator, brushless electric hub motor is made of 0.5 mm thick silicon steel sheet punched and laminated. The outer circle of the silicon steel sheet is punched with evenly distributed holes to place the rotor windings. The inner circle of the silicon steel sheet after the stator core is punched is usually used to punch the rotor core. Generally, the rotor core of the small asynchronous motor is pressed directly on the rotor shaft, while the rotor core of the large and medium-sized asynchronous motor (rotor diameter above 300~400mm) is pressed on the rotor shaft with the help of a rotor bracket.

5. Rotor winding
The rotor winding of a three-phase asynchronous motor cuts the stator rotating magnetic field to produce induction electric potential and current, and form electromagnetic torque to make the motor rotate. Electric vehicle wheel hub motor is divided into a squirrel-cage rotor and wire-wound rotor. The structure of the wire-wound motor is more complicated and not as widely used as a squirrel-cage motor, but the additional resistors and other components are strung in the rotor winding circuit through current collecting ring and brush to improve the starting and braking performance and speed regulation performance of asynchronous motor, so it is used in the equipment requiring smooth speed regulation within a certain range, such as crane, elevator, air compressor and so on.