Hub Motor

 

hub motor is a technology that integrates an electric motor, drivetrain and brake system inside a single hub and is widely used in electric vehicles. Compared with traditional vehicles, it eliminates complex mechanical connections such as the drive shaft, half shaft and steering knuckle, making the transmission system more concise. Through this simplification, it not only significantly improves the transmission efficiency, but also saves valuable interior space, bringing more flexibility to the design and handling of the vehicle.

 

The development of hub motor has gone through three main stages: origin, technological breakthrough and wide application. The concept can be traced back to the end of the 19th century. Around 1890, the first patents for hub motor motors in both direct drive and deceleration configurations were registered, laying the groundwork. With the development of electric vehicle industry, hub motor continues to break through the technical bottleneck, and gradually achieve efficient, compact and intelligent design, which has now become one of the important drive technologies in the field of electric vehicles.

 

 

hub motors can be divided into many types depending on their construction and working principle.

 

1. Divided by motor structure

Inner rotor hub motor : Inner rotor motor has high speed and high power density, small size and light weight. The output torque is amplified through the deceleration structure, but its design is complex, lubrication is difficult, gear wear is fast, and it is not easy to dissipate heat, and the noise is large, so it is less used in practical applications.

 

External rotor hub motor : the external rotor motor has the characteristics of low speed and high torque, no need to decelerate the mechanism, relatively simple structure, less transmission chain, high efficiency. However, its volume and weight are large, the efficiency drops quickly under high loads, and the electric braking capacity is small, requiring additional mechanical braking systems. At present, some enterprises have realized the mass production of external rotor hub motor.

 

2. According to the direction of the magnetic field

Axial magnetic field hub motor : This motor is compact, the stator design has a lot of flexibility, and is able to provide high torque density. However, the control technology is difficult and relatively costly.

 

Radial magnetic hub motor : the technology is relatively mature, the stator design is relatively simple, and it is widely used in the automobile market. Although its efficiency performance is excellent, but the torque density is relatively low.

 

3. Divide by motor type

Permanent magnet hub motor : The use of efficient permanent magnet materials, with high power density and efficiency, widely used in electric vehicles. Its simple structure and fast response speed make it suitable for scenarios requiring rapid acceleration and precise control.

 

Asynchronous hub motor : This motor has strong durability and stability, suitable for some applications that require high reliability. Although its efficiency is slightly lower than that of permanent magnet motors, it has more advantages in cost and manufacturing.

 

Switched reluctance hub motor : simple structure and durable, easy to control, suitable for the need for high torque output occasions. However, the vibration and noise of switched reluctance motors are large, and the design usually needs to be optimized to reduce these effects.

 

4. Divide by drive mode

Direct drive: the motor drives the wheel directly, without the middle transmission mechanism, simple structure, less energy loss, high efficiency. This way reduces the mechanical transmission chain and is suitable for efficient, low-maintenance vehicle designs.

 

Deceleration drive: The output torque of the motor is amplified by the deceleration mechanism for applications where higher torque is required. Although it adds complexity, it can provide greater driving force at low speeds and is suitable for vehicles that are heavier or require more thrust.

 

hub motor, as an advanced technology integrating motor, transmission and braking system, has been widely used in many fields because of its high efficiency and compact characteristics.

 

1. Electric vehicles

hub motor is particularly prominent in electric vehicles. It eliminates the complex drivetrain and makes the interior design more flexible. Because of the absence of mechanical components such as the drive shaft, the weight of the vehicle is reduced, the energy transfer efficiency is improved, and the driving range is significantly improved. In the future, with the expansion of the electric vehicle market, its application in the middle and high-end electric vehicles has broad prospects.

 

2. Electric bicycles

In e-bikes, hub motors are widely adopted due to their advantages of compact construction, low maintenance, and efficient transmission. Compared to traditional motor drive systems, hub motor can provide a more stable power output, making the ride smoother and less noisy. As the demand for urban mobility increases, it will continue to occupy an important position in the field of electric bicycles.

 

3. Electric motorcycles

Electric motorcycles using hub motor can achieve greater instantaneous acceleration, while reducing the complex transmission mechanism of traditional motorcycles. Due to its stable torque output, electric motorcycle riding more comfortable and fast power response, has gradually become an important driving scheme of electric motorcycle.

 

4. Electric scooter

Electric scooters are favored for their portability and flexibility, and hub motor simplifies the body structure, reduces energy loss and improves endurance by providing direct power drive for scooters. Its small size and light weight characteristics also perfectly fit the requirements of lightweight design for electric scooters, and it is expected that there will be a wider range of applications in this field in the future.

 

5. Fitness equipment -- elliptical machine

In the field of fitness equipment, such as elliptical machines, hub motors can be used to provide stable and controlled resistance. Its smooth operation, low noise, and because of the built-in structure does not require frequent maintenance, making it very suitable for home and commercial fitness equipment applications.

 

6. Transport robots

The application of hub motor in automated transportation robots is gradually increasing. These robots require flexible maneuverability and efficient motor drive systems to adapt to different loads and environmental requirements. Due to their high torque and low maintenance characteristics, transport robots can efficiently complete tasks such as handling and distribution. With the advancement of logistics automation, the application of hub motor in this field will be further expanded.

 

hub motor is a relatively simple and efficient way of working, which greatly simplifies the complex drivetrain of a traditional vehicle.

 

1. Electric currents create magnetic fields

When the power is switched on, the current flows into the coils in the motor, creating a magnetic field. This field interacts with a permanent magnet on the rotor, creating a torque that drives the rotor to turn. Because the hub motor is designed to embed the motor directly inside the wheel, this torque can act directly on the wheel to start the vehicle moving.

 

2. Torque transfer with wheel drive

The rotation of the rotor is transmitted directly to the wheels via a transmission, such as a gear or chain, propelling the vehicle forward. Compared to traditional vehicles that rely on clutches, transmissions and drive shafts, hub motors omit these complex mechanical structures and simplify vehicle design. It not only makes the vehicle lighter and saves space, but also improves the efficiency of energy transmission.

 

3. Controller adjustment and precise control

The controller of the hub motor is able to precisely adjust the size and flow of current to control the speed and steering of the motor. By adjusting the current, the vehicle can accelerate, decelerate or maintain a constant speed according to the needs of the driver. This allows vehicles such as electric bicycles to provide a smooth and efficient driving experience for different road conditions and riding needs.

 

1. Measurement of motor speed

When measuring the motor speed, a tachometer or a laser tachometer is usually used. Connect the tachometer to the rotating shaft of the hub motor and determine the output speed of the motor by measuring its revolutions per minute (RPM). In addition, the output signal of the hub motor controller can also be used to monitor the speed more precisely by analyzing the real-time data through software. Measuring the speed helps judge the motor's response under different operating conditions and calibrates its maximum and minimum speed ranges.

 

2. Measurement of motor torque

Measuring the torque of a hub motor can be done using a torque sensor, which is usually installed at the output of the motor. A torque sensor can detect the torque output of the motor under different loads to determine its power output capability. In addition, through the monitoring of the current (the current is proportional to the torque), the torque performance of the motor can also be measured and evaluated indirectly. This data helps judge whether the motor can provide enough driving force to meet the riding demand.

 

3. Comprehensive test of motor performance

The comprehensive performance test is usually carried out on the experimental bench, mainly testing the efficiency of the motor, power output, energy consumption and temperature rise and other indicators. During the test, various working conditions of the motor in actual use (such as different speeds and loads) can be simulated, and various parameters are recorded to evaluate its overall performance. Common test items include maximum power test, efficiency test, heat dissipation performance test and long-term running stability test, etc., to ensure that the motor meets the requirements of use in various performance indicators.

 

4. Check the internal fault of the motor

The inspection of motor internal faults mainly includes coil short circuit, winding fault, bearing wear and controller fault. It is usually possible to check whether the winding is normal by resistance measurement; Motor fault diagnosis tools, such as spectrum analyzers, can also be utilized to detect potential electrical and mechanical failures. In addition, through noise testing and temperature monitoring, it is also possible to tell if there are abnormal conditions inside the motor. Regular fault checks help to detect problems early and extend the service life of the motor.

 

hub motor, driven by innovation and strategic cooperation in the electric vehicle (EV) industry, is showing strong growth momentum and has great potential for future development. As an integrated drive technology, hub motor is gradually being recognized by more enterprises and promoted to be applied to different fields due to its efficiency and structural advantages.

 

1. Application expansion and innovative design of electric vehicles

The development of electric vehicles has provided a huge space for hub motor innovation. Some companies are actively making use of advanced designs such as the dual-rotor radial flux structure to achieve technological breakthroughs in electric vehicles. This design is expected to bring higher torque output and energy efficiency, so that electric vehicles can get more stable and efficient drive support. With the further optimization of technology and the improvement of cost control, the application of hub motor in electric vehicles will accelerate the expansion and promote the performance improvement of electric vehicles.

 

2. Rapid growth of the North American market

Driven by the rapid development of electric vehicles, the North American market is expected to experience the fastest growth in demand for hub motor in the coming years. In particular, driven by the demand for lightweight and efficient energy transmission, the North American market is expected to become a new high ground for the development of hub motor. With the continuous improvement of policy support and related infrastructure, the market potential of North America will be further released, playing an exemplary role for global promotion.

 

3. Cross-industry application expansion

The technological development of hub motor has not only promoted the progress of the electric vehicle industry, but also gradually emerged in other industries. For example, after months of research and development, VSD launched hub motor, which is used in fitness equipment such as elliptical machines. This application brings a smoother, quieter and more efficient drive solution for fitness equipment, showing its potential for a wide range of applications in emerging fields such as sports equipment, smart mobile devices and robotics.

 

4. Future prospects

With the maturity of hub motor technology and the further reduction of manufacturing costs, its application range will be further expanded in the future, covering a variety of scenarios from intelligent vehicles to household appliances. Combined with more intelligent control systems and high-performance materials, hub motor will gradually become the core drive technology in a variety of innovative products, contributing to an efficient, environmentally friendly and intelligent future.

 

 

Choosing VSD as your hub motor suppliers will give you multiple advantages. With more than a decade of experience in motor development and manufacturing, VSD has accumulated deep technical strength and won more than 50 technical patents, always committed to providing high performance motor solutions. VSD's R & D team continues to innovate and has launched a number of hub motors, among which the newly developed external rotor hub motor has been successfully applied to the elliptical machine in fitness equipment, providing a reliable motor choice for more application scenarios.

 

In addition, VSD provides customized service, which can be personalized designed and manufactured according to your specific needs, ensuring a high degree of product matching. We also support customers to visit the factory site, transparent production process, enhance confidence in cooperation. Each type of motor is strictly tested by the latest professional equipment, and accompanied by a detailed test report to ensure the quality, stability and reliability of the product. Choose VSD, you will get first-class hub motor products and service guarantee.