Hub motor is not a new thing, as early as 1900, it has produced a front wheel equipped with motor wheels motor, in the 20th century, 70 years, this technology in the field of mining vehicles and other fields have been applied. As for the passenger car used in the hub motor, Japanese manufacturers for the technology research and development carried out earlier, is currently in a leading position, including GM, Toyota, including the international auto giants are also involved in the technology.
The hub motor drive system is divided into two types according to the rotor type of the motor: inner rotor type and outer rotor type. The outer rotor type adopts the low speed outer rotor motor, the maximum speed of the motor is 1000-1500r / min, no speed reduction device, the wheel speed is the same as the motor. The internal rotor type is used high-speed inner rotor motor, equipped with fixed transmission ratio of the reducer, in order to obtain a higher power density, the motor speed can be as high as 10,000r / min. With the emergence of a more compact planetary gear reducer, the inner rotor type hub motor is more competitive in power density than the low speed outer rotor type.
For conventional vehicles, the clutch, transmission, transmission shaft, differential and even the splitter are essential, and these components are not only light weight, so that the structure of the vehicle is more complex, but also the need for regular maintenance and Failure rate problem. But the hub motor is a good solution to this problem. In addition to the structure is more simple, the use of wheel motor-driven vehicles can get better space utilization, while the transmission efficiency should be much higher.
Because the hub motor has a single wheel independent drive characteristics, so whether it is precursor, rear drive or four-wheel drive form, it can be more easily achieved, full-time four-wheel drive in the hub motor drive to achieve very easy. At the same time the hub motor can be around the wheel at different speeds or even reverse to achieve similar to the crawler vehicle differential steering, greatly reducing the turning radius of the vehicle, in exceptional circumstances can be almost in situ turn (but at this time on the vehicle steering mechanism and Tire wear more), for the special vehicle is very valuable.