The insulation treatment of stator winding is a difficult point in the manufacturing of high-voltage motors, including electromagnetic wire, winding outer insulation, high and low resistance belts, as well as specific links such as winding end binding, varnishing and drying. Partial discharge is a major factor threatening the reliability of the motor; therefore, the insulation structure and process control of the motor must have targeted preventive measures.

Partial discharges usually occur in the insulation structure of high-voltage motors, but the size, quantity and location of partial discharges depend on the motor design, materials, manufacturing process, quality, operating environment and aging condition. For a specific motor design, the characteristics of the insulation materials used, the manufacturing method, the operating conditions, etc. can greatly affect the number, location, characteristics, development trend and significance of partial discharges.



Specific partial discharge measurements and analysis are used for quality control of new windings and winding components as well as for the early detection of insulation defects caused by thermal, electrical, environmental and mechanical stresses in operation, which can lead to insulation failure.