A permanent magnet motor is a DC motor where the stator is a permanent magnet and only the rotor is a coil. While the stator of a normal motor is a coil (electromagnet).
The difference between permanent magnet motors and ordinary motors is:
1, the nature of the magnetic field. Permanent magnet motor is made without external energy to maintain its magnetic field; ordinary motors need electric current into the magnetic field.
2, rotor structure. Permanent magnet motor rotor installed on the permanent magnet poles; ordinary motor rotor installed on the excitation coil.
3, applicable occasions. Permanent magnet motor is usually used in small power occasions; ordinary motor, especially the excitation motor, often used in high-power occasions.
Expanded Information:
Motor in the circuit is represented by the letter M (the old standard with D), its main role is to produce driving torque, as the power source of electrical appliances or various machinery, generator in the circuit is represented by the letter G, its main role is to use mechanical energy converted into electrical energy.
1. According to the type of power supply: can be divided into DC motor and AC motor.
1) DC motor according to the structure and working principle can be divided into: brushless DC motor and brush DC motor.
Brush DC motor can be divided into: permanent magnet DC motor and electromagnetic DC motor.
Electromagnetic DC motor division: series-excited DC motor, parallel-excited DC motor, other-excited DC motor and compound-excited DC motor.
Permanent magnet DC motor division: rare earth permanent magnet DC motor, ferrite permanent magnet DC motor and alnico permanent magnet DC motor.
2) which AC motors can also be divided: single-phase motors and three-phase motors.
2. According to the structure and working principle can be divided: can be divided into direct current motor, asynchronous motor, synchronous motor.
1) synchronous motor can be divided: permanent magnet synchronous motor, reluctance synchronous motor and hysteresis synchronous motor.
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 shaded-pole asynchronous motors.
AC commutator motor can be divided into: single-phase series-excited motor, AC and DC dual-purpose motor and push repulsion motor.
3. According to the starting and running mode can be divided into: capacitor starting single-phase asynchronous motor, capacitor running single-phase asynchronous motor, capacitor starting running single-phase asynchronous motor and split-phase single-phase asynchronous motor.
4. According to the use can be divided into: drive motor and control motor.
1) drive motor can be divided into: electric tools (including drilling, polishing, grinding, slotting, cutting, reaming and other tools) with electric motors, home appliances (including washing machines, electric fans, refrigerators, air conditioners, tape recorders, video recorders, video recorders, video disk players, vacuum cleaners, cameras, hairdryers, electric shavers, etc.) with electric motors and other general-purpose small machinery and equipment (including a variety of small machine tools.), Small machinery, medical equipment, electronic instruments, etc.) with electric motors.
2) control motor is divided into: stepping motor and servo motor.
5. According to the structure of the rotor can be divided into: cage induction motor (the old standard called squirrel cage asynchronous motor) and wire-wound rotor induction motor (the old standard called wire-wound asynchronous motor).
6. According to the operating speed can be divided into: high-speed motor, low-speed motor, constant-speed motor, speed motor. Low-speed motor is divided into gear motor, electromagnetic reduction motor, torque motor and claw pole synchronous motor.
Speed motors can be divided into step constant speed motors, stepless constant speed motors, stepless variable speed motors and stepless variable speed motors, but also can be divided into electromagnetic speed motors, DC speed motors, PWM inverter speed motors and switched reluctance speed motors.
The rotor speed of an asynchronous motor is always slightly lower than the synchronous speed of the rotating magnetic field.
The rotor speed of a synchronous motor is independent of the size of the load and is always maintained at a synchronous speed.
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