Thorough dissection of three-phase asynchronous motors

Thorough dissection of three-phase asynchronous motors - detailed structure of three-phase asynchronous motors
The structure of the three-phase asynchronous motor
(1) Stator (static part)
1. Stator core: The role of the stator core is to serve as a part of the magnetic circuit of the motor, and to place the stator windings on it.
2. Stator winding: The stator winding is the circuit part of the motor, which is fed with three-phase alternating current to generate a rotating magnetic field.
The main insulation items are as follows:
(1) Insulation to ground
(2) Phase-to-phase insulation
(3) Turn-to-turn insulation
Junction box (△ connection method)
The wiring method of stator three-phase winding
(1) Star connection (Y connection)
(2) Delta connection method (△ connection)
3. Machine base
(2) Rotor (rotating part)
The rotor is the rotating part of the motor, including the rotor core, the rotor winding and the rotating shaft.
1. Rotor core
Function: Part of the magnetic circuit of the motor, and place the rotor winding. Generally, 0.5 mm thick silicon steel sheet is punched and laminated. The outer circle of the silicon steel sheet is punched with evenly distributed holes for placing the rotor windings.
2. Rotor winding
The function is to cut the stator rotating magnetic field to generate induced electromotive force and current, and to form electromagnetic torque to make the motor rotate. According to the structure, it is divided into squirrel-cage rotor and wound rotor.
rotor winding
(1) Squirrel cage rotor: If the rotor core is removed, the entire winding looks like a squirrel cage, so it is called a cage winding. Small cage motors use cast aluminum rotor windings, and for motors above 100KW, copper bars and copper end rings are welded.
a) Squirrel winding b) Rotor shape c) Cast aluminum squirrel rotor
(2) Wound rotor: The wound rotor winding is similar to the stator winding, and it is also a symmetrical three-phase winding. Then connect to the external circuit through the brush
3. Spindle
Used to transmit torque and support the weight of the rotor, generally made of medium carbon steel or alloy steel.
(3) Other accessories
End caps, bearings, bearing end caps, fans