When the motor for load switch is in steady state operation, there is a constant relationship between the rotor speed and the grid frequency. If the frequency of the grid is constant, the synchronous motor speed is constant at steady state regardless of the load size. . Synchronous motors are classified into synchronous generators and synchronous motors. The AC machine in modern power plants is dominated by synchronous motors.
Working principle of load switch motor
The establishment of the main magnetic field: the excitation winding is connected with a DC excitation current to establish an excitation magnetic field between the polar phases, that is, the main magnetic field is established.
Current-carrying conductor: A three-phase symmetrical armature winding acts as a power winding and acts as a carrier for inductive or induced current.
Cutting motion: The prime mover drags the rotor to rotate (the mechanical energy is input to the motor), and the excitation magnetic field between the polar phases rotates with the shaft and sequentially cuts the stator phase windings (corresponding to the conductors of the windings to cut the excitation magnetic field).
Generation of alternating potential: Due to the relative cutting motion between the armature winding and the main magnetic field, a three-phase symmetric alternating potential whose magnitude and direction change periodically will be induced in the armature winding. Available through lead wires
Interchangeability and symmetry: Due to the polarity of the rotating magnetic field, the polarity of the induced potential is alternating; due to the symmetry of the armature winding, the three-phase symmetry of the induced potential is guaranteed.