At present,the commonly used winding wires for motor windings are mainly glass wire and thin film wire.The glass wire is tightly wound with alkali free glass wire on bare wire or enameled wire,and soaked and baked with insulating adhesive paint.The mechanical and electrical properties of glass fiber are better than that of enameled wire,and the heat resistance level depends on the heat resistance performance of insulation paint and enameled wire.

　　For the requirements of glass wire,except for dimensional tolerances not exceeding the requirements,when the flat wire is bent 180°on a wide surface,its insulation should not fall off,crack,expose copper or paint,break wires,etc.,and should have insulation resistance and breakdown voltage.

　　Thin film binding wire has high electromechanical performance and is a binding wire with great application value.At present,there are glass fiber winding polyester film winding wire and polyimide film winding wire.The polyimide film binding wire is resistant to high temperature,low temperature and radiation,and has good sealing,electrical aging and abrasion resistance.The space utilization rate of the slot is higher than that of the fiberglass wrapping line.Glass fiber wrapped polyester film wrapped wires have good mechanical and electrical properties,but the insulation layer is thick.