Analysis of the working principle of a stepper motor the interaction between magnetic field and current

    Step motor is a precision control device widely used in automation systems, which achieves accurate position and speed control through the interaction of magnetic field and current. Below, we will analyze the working principle of a stepper motor and provide a detailed introduction to how the magnetic field and current interact to drive the motor to rotate.
 

    Magnetic pole and magnetic field:
 

    The rotor of a stepper motor usually contains multiple magnetic poles, which are made of permanent magnet materials or electromagnetic coils. When current passes through the coil in the motor, a magnetic field is generated. This magnetic field can be generated by a permanent magnet or by a coil excited by an electric current.
 

    Coil and current:
 

    The stator of a stepper motor usually contains multiple coils, which are connected to a power source and driven by current. The direction and magnitude of the current determine the strength and direction of the magnetic field. According to different control methods, the current can flow in one direction or in the opposite direction as needed.
 

    Interaction between magnetic field and coil:
 

    When current passes through the coil of a stepper motor, the magnetic field generated by the coil will interact with the magnetic field of the rotor. According to the principle of interaction, there is an attraction or repulsion force between the coil and the rotor, which causes the motor to rotate.
 

    Magnetic field changes and rotor motion:
 

    In a stepper motor, different magnetic field changes can be generated by changing the direction and magnitude of the coil current, thereby driving the rotor to move. For example, when the magnetic field of the coil is attracted to the magnetic field of the rotor, the motor will rotate to align the coil with the rotor. When the magnetic field of the coil repels the magnetic field of the rotor, the motor will rotate to move the coil away from the rotor.
 

    In summary, the working principle of a stepper motor is based on the interaction between magnetic field and current. By controlling the direction and magnitude of coil current, stepper motors can achieve accurate position and speed control. The change in magnetic field drives the rotor to move, and different stepping angles and driving sequences determine the stepping mode of the motor. These principles and control methods make stepper motors a commonly used precision control device in automation systems, widely used in various industrial and commercial fields.