Sale Shanghai Electric Power Generation Motor Slot Wedges and Stator or Rotor

Large-scale generators are one of the three major mainframes of modern power plants and belong to the core equipment of power plants. Damage to generators will cause huge economic losses to power plant production and operation, and even threaten the power supply security of the power grid in the core load area. Therefore, it is very important to ensure the safe and stable operation of large-scale generator sets, and the stator bars, which are the most important components of the generator, will be subjected to alternating magnetic field forces during operation. Due to the quiver of the iron core, the main insulation material will undergo slight thermal expansion and contraction. As a result, the wedges are seriously loosened and partially detached, which in turn exacerbates the vibration of the bar. The mechanical strength and dielectric properties of the main insulation tend to deteriorate. Long-term operation will lead to wear of the insulation layer, causing eddy currents and spark discharges, resulting in electric corrosion. Until the insulating layer breaks down, it eventually leads to a generator short-circuit accident and damage. Therefore, it is particularly important to periodically check the tightness of the stator wedge. During the overhaul period of our plant, we detected the tightness of the generator slot wedge after the rotor has been extracted as a key generator overhaul project. More than half of the slot wedges were found after the professional technicians together with the motor manufacturer technicians inspected the stator slot wedges. Below the Leeb hardness test standard. After consultation with power plant professionals, power plants, research institutes and power plants of the same type, the power plant professionals held a special seminar to determine the treatment opinions, scope, and plans.
        1 Stator slot wedge fixing structure
        The conventional slot fixing method of the generator factory is that after the stator bar is inserted into the stator slot, it is fastened with a pad strip and a slot wedge, as shown in FIG. 1 . This fixing method makes the slot wedge and the bar rigid. Contact, due to thermal expansion and contraction phenomenon and long-term operation of the insulation material such as a certain shrinkage, groove wedge will appear loose phenomenon

Large-scale generators are one of the three major mainframes of modern power plants and belong to the core equipment of power plants. Damage to generators will cause huge economic losses to power plant production and operation, and even threaten the power supply security of the power grid in the core load area. Therefore, it is very important to ensure the safe and stable operation of large-scale generator sets, and the stator bars, which are the most important components of the generator, will be subjected to alternating magnetic field forces during operation. Due to the quiver of the iron core, the main insulation material will undergo slight thermal expansion and contraction. As a result, the wedges are seriously loosened and partially detached, which in turn exacerbates the vibration of the bar. The mechanical strength and dielectric properties of the main insulation tend to deteriorate. Long-term operation will lead to wear of the insulation layer, causing eddy currents and spark discharges, resulting in electric corrosion. Until the insulating layer breaks down, it eventually leads to a generator short-circuit accident and damage. Therefore, it is particularly important to periodically check the tightness of the stator wedge. During the overhaul period of our plant, we detected the tightness of the generator slot wedge after the rotor has been extracted as a key generator overhaul project. More than half of the slot wedges were found after the professional technicians together with the motor manufacturer technicians inspected the stator slot wedges. Below the Leeb hardness test standard. After consultation with power plant professionals, power plants, research institutes and power plants of the same type, the power plant professionals held a special seminar to determine the treatment opinions, scope, and plans.
        1 Stator slot wedge fixing structure
        The conventional slot fixing method of the generator factory is that after the stator bar is inserted into the stator slot, it is fastened with a pad strip and a slot wedge, as shown in FIG. 1 . This fixing method makes the slot wedge and the bar rigid. Contact, due to thermal expansion and contraction phenomenon and long-term operation of the insulation material such as a certain shrinkage, groove wedge will appear loose phenomenon