Analysis of rotor current magnetic field machinery.

To start the process of starting process of mechanical transmission system of production machinery and motor or spindle, which is also a process of spindleby still reach rated speed. Due to the rotational speed of the spindle in a very short period of time from zero to the rated speed, therefore, must produce the inertia force. The production of mechanical and electricalhypothesis is not connected to the clutch, the system startup process is the starting process of motor. Asynchronous motor during startup, the a=d ω /dt>0, but is not equal to the constant

When the power supply is cut off when the motor stator winding, stator current in the rotor speed is zero, but for the rated speed, the rotorcurrent is difficult to be measured is not calculated, so the rotor currentform a rotating magnetic field in the stator winding in the AC inductionelectromotive force, because of the connection, the stator winding type Y is not closed, so no induction the stator winding current, had no effect on therotor operation, so the rotor current by exponential decay, while the rotorelectromagnetic torque and rotor current is proportional to the square of the rotor, so the electromagnetic torque is the exponential decay, to a moment to zero.

Rotor current in the three-phase stator winding on the formation of three-phase rotating magnetic field, and the induced electromotive force, thethree-phase stator winding end to end to form a closed loop, so the statorcurrent form, the rotor to a stator of the motor acts as a generator; stator current and the formation of three-phase rotating magnetic field on therotor, the magnetic field of the stator impede rotation, so the rotor on the formation of braking torque.

Effect on the important production machinery and transmission, withmechanical load, voltage fluctuation and other occasions started frequentlymust consider the inertial force, so it is necessary to seize the main aspects of inertia force was analyzed and calculated, and take the necessary measures to reduce the impact.