The characteristics of motor products are the relative stillness of the stator and the relative movement of the rotor during operation. Usually, we use the relatively still parts as the input or output of the power supply. For motor products, the power supply is input through the stator; and for generators, the power is also output by the stator. So, why not connect the power supply to the rotor of the motor?
Let us first understand the wound rotor motor, that is, the rotor of the motor is wound with electromagnetic wire. The processing and fixation of the rotor winding of this type of motor is very important. On the one hand, it is necessary to ensure the adverse effects of centrifugal action on the winding during the operation of the rotor, and on the other hand, it is necessary to ensure the adverse effects of vibration on the winding insulation system during the movement of the rotor. Therefore, wound rotor motors are generally multi-pole low-speed motors, and motors with 4 poles and higher speeds are not suitable for wound rotors. A typical fault of wound rotor motors is called "dumping", that is, the rotor winding end is severely deformed or even burned due to the motor running at a speed exceeding the rated speed. From this we can draw a conclusion that from the perspective of quality stability, the winding part of the motor will be installed on the stator in a stationary state.
From the perspective of electrical connection, when the power supply is connected to the moving rotor, it must be indirectly connected through a slip ring structure. On the one hand, there is structural complexity, and on the other hand, it is also very important to have the reliability of the connection. In view of the above, the power supply of motor products preferably uses a stationary stator, which can also be called the primary component of the motor, and tries to avoid connection with the moving rotor. According to the above principles, whether it is an inner rotor motor or an outer rotor motor, the rotating part is basically the secondary component of the motor.
low voltage electric motor, Ex motor, Motor manufacturers in China, three phase induction motor, SIMO motor