What is the dynamic braking process of three-phase asynchronous motor

Dynamic braking control of three-phase asynchronous motor is a common control method. The working principle and control process of dynamic braking, as well as the mechanical characteristics of dynamic braking, will be further elaborated. The principle of energy consumption braking and the control process The principle of energy consumption braking of three-phase motors, assuming that the original motor is connected to the power grid and running in the forward electric state, its speed is n, and the stator of the running motor is moved from The three-phase AC power supply is disconnected, and at the same time, the DC current is passed into the stator winding, so that the DC current flowing through the stator winding will form a fixed, non-rotating spatial magnetic field in the air gap of the motor. At the moment after the power is cut off, the rotor speed of the motor cannot change suddenly due to inertia, so relative to the speed, the constant space magnetic field generated by the DC current is a rotating magnetic field. The speed of the rotor is n and it rotates counterclockwise. Standing on the rotor, the constant space magnetic field rotates clockwise, and the speed is also n. Just as the motor is running in the electric state, the rotor and the space magnetic field have relative motion. The induced electromotive force E and the induced current I are generated in the winding. The rotor current I interacts with the constant space magnetic field to generate electromagnetic force and electromagnetic torque Te. The direction of the electromagnetic torque Te is opposite to the direction of the rotor speed, and the motor enters the braking state. Under the action of Te, the rotating speed of the rotor decreases. If the electric motor drags a directional load, the rotating speed of the electric motor quickly decreases to zero.