Generation of brushless DC motors
At present, the DC brushless motor is a new type of motor with rapid development in the field of micro power. Since each application field requires its own unique brushless DC motor, there are many types of brushless DC motors. Generally, there are computer external memory and flat ironless motor structure for VCD, DVD, CD spindle drive, outer rotor motor structure for small ventilator, multi-pole magnetic field structure and built-in structure for household appliances, multi-pole and outer rotor for electric bicycles structure, etc. The motor itself and the circuit of the above-mentioned brushless DC motor are integrated, which is very convenient to use, and its output is also very large. In order to meet the high-volume, low-cost market demand, the production of brushless DC motors must form economies of scale. Therefore, the DC brushless motor is a high-input and high-output industry. At the same time, we should take into account the continuous development of the market. For example, the motor for household air conditioners is changing from 3A to 3D, which requires a large number of small and medium-power brushless DC motors. Research and development of small and medium-power brushless DC motors has also become a top priority.
Brushless DC motor (BLDCM) is developed on the basis of brushed DC motor, but its driving current is an uncompromising AC; BLDCM can be divided into brushless speed motor and brushless torque motor . Generally, there are two types of drive currents for brushless motors, one is a trapezoidal wave (usually a "square wave"), and the other is a sine wave. Sometimes the former is called a DC brushless motor, and the latter is called an AC servo motor, which is exactly a type of AC servo motor.