The stator winding of three-phase asynchronous motor is the circuit part of the motor, which will establish magnetic field through current, induce electromotive force and realize electromechanical energy conversion. Each phase of the three-phase stator winding is embedded in the core slot by many coils according to certain rules, which can be single-layer, double-layer, full-distance or short-distance. It is very necessary to know the embedding technology and connection method of stator winding for the manufacture and maintenance of motor.