Brushless DC motor is widely used in automobile, tools, industrial control, automation, aerospace and so on. In general, brushless DC motor can be divided into the following three main purposes:
Continuous load application: It is mainly used in fields that require a certain speed but do not require high speed accuracy, such as fans, water pumps, hair dryers and other applications. Such applications have low cost and are mostly open-loop control.
Variable load application: mainly refers to the application where the speed needs to change within a certain range, and has higher requirements for the motor speed characteristics and dynamic response time characteristics. For example, household appliances, dryers and compressors are good examples. The system cost of oil pump control, electric controller, engine control, etc. in the automotive industry is relatively higher.
Positioning application: most industrial control and automatic control applications belong to this category. In such applications, energy transmission is often completed, so there are special requirements for the dynamic response of speed and torque, as well as for the controller. Photoelectric and some synchronization equipment may be used for speed measurement. Process control, mechanical control and transportation control are all of these applications.
The new practical brushless motor is closely related to the development of electronic technology, microelectronics technology, digital technology, automatic control technology and material science. It is not only limited to the field of AC and DC, but also involves the fields of electric, power generation energy conversion and signal sensing. There are many new types of brushless motors in the motor field, but the excellent performance brushless motors are not widely used because of the price constraints. The main new brushless motor is explored and studied below.