The rotation of the three-phase asynchronous motor principle

Three-phase asynchronous motor to spin the prerequisite is to have a rotating magnetic field,three phase asynchronous motor stator winding is used to produce a rotating magnetic field.As we know,but that power facies phase difference is the voltage on the phase between 120 degrees,three of the three-phase asynchronous motor stator winding on the spatial orientation also sent 120 degrees,so,when in the stator Winding zhongtong into the three-phase power supply,the stator windings creates a rotating magnetic field.Current every change is a cycle,a rotating magnetic field in a week,between the rotational speed of a rotating magnetic field and electric current of change Is synchronized.The speed of the rotating magnetic field acmotortrading.blogspot.com is: n = 60 f/P type in f P is the power supply frequency,magnetic field of magnetic pole unit is logarithmic,n: revolutions per minute.According to the type we know,the speed of the motor Associated with the frequency of pole number and the use of power.Only one winding single-phase ac motor,the rotor's cage.When a single-phase sinusoidal current in the stator winding,motor can produce an alternating Magnetic field,the magnetic field strength and direction of interplanting sine law of change at any time,but on the spatial orientation is fixed,so the magnetic field is also called alternation pulse magnetic field.The alternation pulse magnetic field can be broken For the two at the same speed and direction of rotation are opposite rotating magnetic field,when the rotor static,the two rotating magnetic field generated in the rotor torque pumps of two equal and opposite,making synthetic Moment is zero,so the motor can't rotate.When we use the motor rotates in the direction of a force (clockwise),then the rotation of the rotor and clockwise direction magnetic field between the cutting Cut the lines of magnetic force movement smaller;The rotation of the rotor and counterclockwise direction magnetic field cutting lines generator rotor and stator of magnetic force between the movement.This balance is broken,the total electromagnetic torque generated by the rotor will no longer be zero, Rotor spun along the driving direction.