Outrunner Brushless Motor for Electric Bike
Electric bikes are generally welcomed by the majority of consumers because they are light and fast and adapt to the modern need for environmental protection, efficiency and safety. As a green transportation, electric vehicles require high motor efficiency and high adaptability. Motor is the key of electric bike technology, and the progress of motor technology and the development of power electronics technology are closely related. Under the condition of limited energy, the efficiency of the motor directly affects the main whole index of the electric bike, its volume, weight and appearance also directly affect the shape of the whole electric bike, and the reliability of the motor also directly affects whether the electric bike can be received by the majority of consumers.
Due to cost and space constraints, the high-density, compact, lightweight and low-cost of the motor are critical to the electric bike. Brushless DC motors are widely used in electric bicycles because of their advantages of brushless and mechanical commutators, no need for speed reduction devices, and low noise. Brushless DC motors are widely used in electric bicycles because they have the following advantages over traditional brushed DC motors: long life, maintenance-free, and high reliabilit
In the brushed DC motor, due to the high speed of the motor, the brushes and commutator wear faster, and generally need to replace the brushes after about 1000 hours of work. In addition, the technical difficulty of its reduction gear box, especially the lubrication of the rotating gears, is a relatively large problem of the brushed motor. Therefore, brushed motors have problems such as high noise, low efficiency, and prone to failure. Therefore, the advantages of brushless DC motor are obvious.
In the application of electric bikes, it is estimated that if the service life of brushed motor is 80,000km, then the service life of brushless DC motor is more than 200,000km. Compared with brushed motor, the controller of brushless motor is relatively complex, and the control part has increased the electronic commutation, so that the reliability and economy of controller are greatly improved. Brushless DC motor is widely used in electric bicycle because of its advantages such as no brush and mechanical commutator, no deceleration device and low noise.
Advances in outrunner brushless motor technology are mainly in the form of small size, light weight and high efficiency. This is a great advancement for electric bikes, which are supposed to be light and handy. The small size, light weight and high efficiency of outrunner motors are closely related to the development of magnetic materials. The quality and lifespan of outrunner brushless motors are much higher and longer than those of brushed motors. Outrunner brushless motors allow trams to run continuously for up to several thousand hours without maintenance. The service life of brushless motors is much longer than that of brushed motors.
