Regarding the working principle of motors, due to their basic similarity, we will take DC motors as an example for detailed analysis. Tubular motor is a type of DC motor, and its working principle is basically the same.
A DC motor consists of two parts: the stationary part and the moving part. The stationary part is generated by an external magnetic field through a constant electromagnet and is called a stator. The moving part is composed of a rotor, whose main characteristic is rotation in a constant magnetic field. This magnetic field maintains a constant magnetic flux through the stator core, and the permanent magnet can serve as a replaceable electromagnet, providing the stator magnetic field without the need for complex structures.
The current driven by the DC power supply passes from the positive pole of the battery through a coil wound on the iron core with a wire, or through a carbon brush inserted on the side to drive the entire system. When this current passes through the coil, it will change the direction of the magnetic field. If the speed of this magnetic field change is relatively slow, the force of the magnetic field on the iron core will also be relatively small, and an opposite magnetic field will also be generated on the other side of the iron core, which is a reactive force and loses some magnetic energy. On the other hand, if this current repeatedly affects the iron core, it will also cause the rotor to rotate.
