Dongguan Langyi Electromechanical Technology Co., Ltd.

业界资讯

Insulation bandaging and insulation failure analysis of high voltage motor coils



[Guide] The strapping process should ensure the maximum fit between the strapping and the winding, and the strap to the strap to prevent the formation of air gaps between each other, which will affect the final dipping and curing effect, and even cause motor Discharge phenomenon will directly affect the performance level of the motor.


Compared with ordinary motor windings, the manufacturing process of high-voltage motor coils is more complicated. Several layers of mica tape must be wrapped on the outside of the forming coil, and low- and high-resistance bands must be added.




MetInfo enterprise content manager system | MetInfo CMSMetInfo enterprise content manager system | MetInfo CMS

MetInfo enterprise content manager system | MetInfo CMSMetInfo enterprise content manager system | MetInfo CMS



There are three methods of mica band banding: pure manual, semi-automatic and fully automatic. During the bandaging process of mica band, the basic requirements of uniform banding thickness, consistent tightness and no breakage must be met. In actual operation, the effect of full-automatic bandaging It is best to eliminate the interference of various human factors. In contrast, in the case of semi-automatic and manual operation, there will always be some uncertain factors whether it is the consistency of the stacking or the degree of tension.


The wrapping process should ensure the maximum fit between the wrapping band and the winding, as well as to prevent the formation of air gaps between each other, which will affect the final dipping and curing effect, and even cause the motor to discharge. Directly Affects the performance level of the motor.


It should also be emphasized that the low-resistance band wrapped at the straight edge of the coil and the high-resistance band wrapped at the slot position, while strengthening the insulation, prevent the occurrence of corona, so the band must not be damaged.


1 Characteristics of high voltage motor coil corrosion


In general, the coils of high-voltage motors are not prone to quality problems, but the problems of corrosion and aging of the insulation also occur under sufficient operating time and under the influence of internal and external environments. From the perspective of the breakdown of the main insulation of the high voltage motor stator winding coil, the corrosion damage of the main insulation of the coil can be roughly divided into two cases: one is from the outside to the inside, which is usually called external corrosion; the other is Inside-out corrosion is often called internal corrosion.


2 introduction of external corrosion damage


● During the operation of the motor, due to the vibration of its end windings under the influence of electromagnetic force, the coils in the stator core slots are not fixed firmly at the ends, and slot wedges, coil interlayer spacers, end spacers, and The binding rope loosens and falls, friction occurs between the coil and the binding rope and the spacer, and the anti-corona semiconductor paint and the belt are damaged by corona corrosion, which causes the main insulation of the groove and the end of the coil to break down.


● Conductive foreign objects such as iron filings inside the stator core are attracted to the main insulation surface of the coil when the motor is running. Under the influence of electromagnetic induction and electromagnetic force, the magnetic objects move in a rotating manner, which will wear away the main insulation of the coil.





Record nuber Gangdong ICP NO :17115209