From the perspective of use, the difference between high and low voltage motors is the difference in rated voltage between the two, but for the manufacturing process, the difference between the two is still very large.
Due to the difference in rated voltage of the motor, the difference in clearance and creepage distance between high-voltage motor and low-voltage motor parts is determined. Regarding the requirements in this regard, GB/T14711 has specific chapters to make provisions. Around this requirement, The design of the two types of motor parts must have essential differences in some related links, such as the motor junction box part, the junction box of the high-voltage motor is obviously larger.
In terms of material selection, the electromagnetic wires, insulating materials and lead wires used for high-voltage motors are very different from the corresponding materials of low-voltage products. Most of the stators of high-voltage motors use thick-insulated electromagnetic flat wires, which need to be placed on the outside of each coil. With multi-layer mica insulating material, the higher the rated voltage of the motor, the more layers of mica material to be added; in order to prevent the harm to the winding caused by the corona problem during the operation of the high-voltage motor, in addition to the necessary design avoidance measures, also To add anti-corona corona paint or resistance tape between the coil and the iron core of the motor. In terms of lead wire, the conductor diameter of the lead wire of the high-voltage motor is relatively small, but the insulation sheath of the lead wire is very thick. In addition, in order to ensure the relative insulation requirements of the high-voltage motor and related components, an insulating windshield will be used in the stator winding part, and the windshield will also play the role of wind guide.
Insulation handling requirements for bearing systems. Compared with low-voltage motors, high-voltage motors will generate significant shaft current. In order to prevent shaft current problems, the bearing system of high-voltage motors should take necessary precautions. According to specific conditions such as motor size and operating conditions, insulating carbon brushes are sometimes used. Bypass measures, and sometimes the use of insulating end caps, insulating bearing sleeves, insulating bearings, insulating journals and other circuit breaking measures.
The above are the main differences between high and low voltage motors at the manufacturing level. Therefore, the manufacture of high voltage motors and low voltage motors are two relatively independent systems, and the key control points of the two motor manufacturing processes are different.
Post time: Jul-22-2022