A motor is an electromagnetic device that converts or transmits electrical energy according to the laws of electromagnetic induction, or converts one form of electrical energy into another.
An electric motor converts electrical energy into mechanical energy, and a generator converts mechanical energy into electrical energy.
The motor is represented in the circuit by the letter "M" (the old standard was "D").
Its main function is to produce a driving torque, as electrical or mechanical power source.
Summary of classification
1. According to the type of working power supply, it can be divided into dc motor and ac motor.
1) according to the structure and working principle, the dc motor can be divided into brushless dc motor and brushless dc motor.
Brushless dc motor can be divided into permanent magnet dc motor and electromagnetic dc motor.
Electromagnetic dc motor division: series dc motor, parallel dc motor, other dc motor and compound dc motor.
Permanent magnet dc motor classification: rare earth permanent magnet dc motor, ferrite permanent magnet dc motor and alnico permanent magnet dc motor.
2) ac motor can be divided into single-phase motor and three-phase motor.
2, according to the structure and working principle can be divided into: dc motor, asynchronous motor, synchronous motor.
1) synchronous motor can be divided into permanent magnet synchronous motor, reluctance synchronous motor and hysteresis synchronous motor.
2) induction motor can be divided into induction motor and ac commutator motor.
Induction motor can be divided into three - phase induction motor, single - phase induction motor and cover asynchronous motor.
Ac commutator motor can be divided into single-phase series motor, ac and dc motor and repulsion motor.
3. It can be divided according to the starting and running mode: single-phase asynchronous motor with capacitor starting, single-phase asynchronous motor with capacitor running, single-phase asynchronous motor with capacitor starting and running and single-phase asynchronous motor with phase splitting.
4, according to the use can be divided: drive motor and control motor.
1) drive motor can be divided into: electric tools, including drilling, polishing, grinding, slotting, cutting, reaming tools such as motor, household appliances, including washing machines, electric fans, refrigerators, air conditioner, tape recorder, video recorder, VCD, vacuum cleaners, cameras, hair dryer, electric shaver, etc.), motor and other general small mechanical equipment (including all kinds of small machine tools, small machinery, medical equipment, electronic instruments, etc.) motor.
2) control motor is divided into stepper motor and servo motor.
5, according to the structure of the rotor can be divided: cage induction motor (the old standard called squirrel cage induction motor) and wound rotor induction motor (the old standard called wound asynchronous motor).
6, according to the speed of operation can be divided into: high speed motor, low speed motor, constant speed motor, speed motor.
Low speed motor is divided into gear reduction motor, electromagnetic reduction motor, torque motor and claw synchronous motor.
Speed regulating motor can be divided into stepless constant speed motor, stepless constant speed motor, stepless variable speed motor and stepless variable speed motor, but also can be divided into electromagnetic speed regulating motor, dc speed regulating motor, PWM variable frequency speed regulating motor and switched reluctance speed regulating motor.
The rotor speed of an asynchronous motor is always slightly lower than the synchronous speed of a rotating magnetic field.
The rotor speed of synchronous motor is always kept at synchronous speed regardless of the load.
Dc generator working principle
The working principle of the dc generator is to change the induction of the alternating electromotive force in the armature coil into a direct current electromotive force by means of the commutator and the commutating action of the brush.
The direction of the induced electromotive force is determined according to the right hand rule (the magnetic induction line points to the palm, the thumb points to the direction of conductor movement, and the other four fingers point to the direction of the induced electromotive force in the conductor).
The working principle of dc motor
The direction of force on a conductor is determined by the left-hand rule.
This pair of electromagnetic forces creates a torque on the armature, called the electromagnetic torque in the rotating motor, which is counterclockwise in an attempt to turn the armature counterclockwise.
If the electromagnetic torque overcomes the resistance torque on the armature (such as friction resistance torque and other load torque), the armature can rotate counterclockwise.
The principle structure of dc motor
Dc motor is the motor running on dc working voltage, widely used in radio recorder, video recorder, DVD player, electric shaver, electronic watch, toys and so on.