The technology of wheel hub motor, also known as in-wheel motor technology, is characterized by integrating power, transmission and braking devices into the wheel hub, which greatly simplifies the mechanical part of electric vehicles. The technology of wheel hub motor is not a new thing. As early as 1900, electric cars equipped with wheel hub motors were produced for front wheels. In the 1970s, this technology was applied in fields such as mine transportation vehicles.
Wheel hub motors omit a large number of transmission components, make vehicle structure simpler, and can achieve various complex driving modes, which is convenient for adopting various new energy vehicle technologies. We can use methods such as back-electromotive force method, freewheeling diode method and inductance method to detect sensor position signals. So, how does the wheel hub motor compare with traditional motors?
Compared with traditional motors, why aren't advanced wheel-mounted motor electric vehicles equipped on a large scale? In fact, the principle of the electric wheel hub motor is not much different from that of traditional motors, but its structure is more complex. This means that there are fewer coils and the magnetic field is not as strong as that of traditional motors, so the output power is relatively small. In addition, there are two types of wheel hub motors: internal rotation motor and external rotation motor. The rotor of the external rotation motor is located inside the stator, like a traditional motor. The rotor of the external rotation motor is located outside the stator and rotates around the stator. The wheel hub motor integrates the power device, transmission device and braking device into the wheel hub, greatly simplifying the mechanical part of electric vehicles.
Due to the limited diameter of the wheel hub and the width of the tire, the maximum size of wheel hub motors is not as large as that of traditional motors, and the output power is difficult to achieve. Therefore, many wheel hub motors are only used for two-wheeled electric vehicles. Compared with traditional motors, wheel hub motors have many significant advantages. First of all, this design does not have transmission loss because there is no transmission rod from the engine to the wheel, so the efficiency is very high. In addition, the wheel hub motor can reverse the speed of the left and right wheels to achieve differential steering like a tracked vehicle, greatly reducing the turning radius of the vehicle. In special cases, it can almost achieve turn on the spot, which is commonly known as a tank turn. In terms of loading space, wheeled vehicles also have advantages in having large suitcases in the front and back.