Brushless DC Motor and Its Characteristics

What is a brushless DC motor ?
 
A brushless DC motor (BLDC) consists a motor and a drive. It's a typical mechatronic product. A brushless DC motor refers to a motor without a brush and a commutator (or a slip ring). It's also known as a non-commutator motor. As a matter of fact, earlier in the 19th century, when motors were invented, the most practical type was brushless, which was called AC squirrel-cage induction motors. These motors were widely applied in various industries. However, there were a lot of shortcoming with induction motors and the technology developed very slowly. By the mid-20th century, transistors were invented, so that brushless DC motors, in which electric brushes and commutators have been replaced with transistors, were born. This new model of brushless DC motor is called electronically commutated brushless DC motor. They have overcome the flaws of the first generation.
 
Characteristics of brushless DC motors
 
1. Have the advantages of traditional DC motor , but have cancelled the carbon brush and slip ring structure
2. Have brake and dual steering functions
3. Small size, light weight , large output 
4. Excellent torque characteristics , good mid-to-low-speed torque performance, high starting torque, low starting current 
5. Variable speed, wide speed range, strong overload capacity
6. Good braking characteristics, can save the original mechanical brake or electromagnetic brake device
7.  High-efficiency, the motor itself has no excitation loss and the loss of carbon brush, eliminating the multi-stage reduction loss , so has a comprehensive energy-saving rate of 20% to 60%
8. High reliability, good stability and adaptability. Repair and maintenance is simple
9. Resistant to bumps vibration, low noise, low vibration, smooth operation and long service life 
10. Do not produce sparks, so good for working in explosive places. Some models are explosion-proof
11. Customers can choose from trapezoidal wave sinusoidal magnetic field motors or sinusoidal magnetic motors according to needs.