Motor (English: Electric machinery, commonly known as "motor") refers to an electromagnetic device that realizes electric energy conversion or transmission according to the law of electromagnetic induction. In the circuit, it is represented by the letter m (the old standard is d). Its main function is to generate driving torque as the power source of electrical appliances or various machinery. The generator is represented by the letter g in the circuit. Its main function is to convert electric energy into mechanical energy.
1. According to the type of working power supply, it can be divided into DC motor and AC motor.
1) DC motors can be divided into brushless DC motors and brushed DC motors according to their structures and working principles.
Brushed DC motors can be divided into permanent magnet DC motors and electromagnetic DC motors.
Electromagnetic DC motors are divided into series excited DC motors, parallel excited DC motors, separately excited DC motors and compound excited DC motors.
Permanent magnet DC motors are divided into rare earth permanent magnet DC motors, ferrite permanent magnet DC motors and Al-Ni-Co permanent magnet DC motors.
2) Among them, AC motors can also be divided into single-phase motors and three-phase motors.
2. According to the structure and working principle, it can be divided into DC motor, asynchronous motor and synchronous motor.
1) synchronous motors can be divided into permanent magnet synchronous motors, reluctance synchronous motors and hysteresis synchronous motors.
2) Asynchronous motors can be divided into induction motors and AC commutator motors.
Induction motors can be divided into three-phase asynchronous motors, single-phase asynchronous motors and shielded pole asynchronous motors.
AC commutator motor can be divided into single-phase series motor, AC -DC dual-purpose motor and repulsion motor.
3. According to the starting and running modes, it can be divided into three types: capacitor-started single-phase asynchronous motor, capacitor-operated single-phase asynchronous motor, capacitor-started single-phase asynchronous motor and split-phase single-phase asynchronous motor.
4. According to the purpose, it can be divided into drive motor and control motor.
1) drive motors can be divided into: motors for electric tools (including drilling, grinding, polishing, slotting, cutting, reaming, etc. ), motors for household appliances (including washing machines, electric fans, refrigerators, air conditioners, tape recorders, video recorders, DVD players, vacuum cleaners, cameras, hair dryers, electric razors, etc.). ) and other general small mechanical equipment (including various small machine tools).
2) Control motors are divided into stepper motors and servo motors.
5. According to the rotor structure, it can be divided into squirrel-cage induction motor (old standard called squirrel-cage asynchronous motor) and wound rotor induction motor (old standard called wound asynchronous motor).
6. According to the running speed, it can be divided into high-speed motor, low-speed motor, constant-speed motor and variable-speed motor. Low-speed motors are divided into gear reduction motors, electromagnetic reduction motors, torque motors and claw-pole synchronous motors.
Speed regulating motors can be divided into step constant speed motors, stepless constant speed motors, step variable speed motors and stepless variable speed motors, as well as electromagnetic speed regulating motors, DC speed regulating motors, PWM frequency conversion motor and switched reluctance speed regulating motors.
The rotor speed of asynchronous motor is always slightly lower than the synchronous speed of rotating magnetic field.
Regardless of the load, the rotor speed of the synchronous motor is always kept at the synchronous speed.