DC motors and AC motors have a wide range of applicatio […]
DC motors and AC motors have a wide range of applications. The basic principles of the two are consistent. Both have their own advantages and disadvantages. According to the analysis, DC motors have commutators, which is also an important reason for determining the different working modes of DC motors and AC motors.
Take the example of a motor. If the motor is to work, the rotor must be driven by the electromagnetic force felt by the rotor winding. Therefore, in order to ensure stable and continuous rotation of the motor, the induced electromagnetic force in the rotor winding must be kept in the same direction. For a DC motor, the direction of the stator magnetic field remains the same. If the current in the rotor does not reverse, the direction of the electromagnetic force on the rotor changes during the rotation process, and the continuous rotation of the rotor cannot be guaranteed.
When the AC motor is working, this is ensured by changing the direction of the stator magnetic field. Because the stator magnetic field of the AC motor is not fixed, but rotates according to a certain law, it can ensure that the direction of the electromagnetic force on the rotor winding remains unchanged. As long as the stator coils are arranged in phase, a rotating magnetic field is naturally generated to ensure the rotation of the rotor.
The working principle of DC motors and AC motors is the law of electromagnetic induction, but there are also differences between them. This can be understood from two different starting methods. The rotor rotation (armature winding motion or force) of the DC motor is due to the electromagnetic force of the armature winding in the magnetic field, so the premise is that there is current in the armature, so the armature current is required to start the DC NanYang Motor . As long as the AC motor is activated by AC on the stator, there is a rotating magnetic field. Since the magnetic field is moving, the rotor winding will sense the electromotive force. As long as the rotor winding can form a closed loop, an electric current is generated and an electromagnetic force is generated to drag the rotor to rotate. Therefore, the premise of the AC motor rotor motion is that the magnetic field is rotating, which is the difference between the two in the initial motion state.