The demand for 10kV motors is greater than that for 6kV motors, and upon careful consideration, it is indeed not without reason. In recent years, with the implementation of energy-saving policies and the upgrading of domestic power grids to reduce line losses, industrial and mining enterprises have been choosing medium-sized 10kV motors to replace 6kV motors in order to reduce distribution investment, leading to a significant increase in the demand for medium-sized 10kV motors. One of the technical challenges of such motors is the inter-turn insulation of the stator coils. Due to the often thin conductors, it is difficult to use either hand-wrapped or machine-wrapped mica tape. Using the inherent insulation of film-wrapped wires as inter-turn insulation results in poor resistance to corona. In high-voltage motor failures, inter-turn faults account for a large proportion, and the reliability of inter-turn insulation has increasingly attracted attention. Some users even specify that high-voltage motors should use mica for inter-turn insulation.
The measures taken abroad in this regard are the extensive use of mica wrapped wires. In China, research on inter-turn insulation with powder mica tape has been carried out in recent years. With the assistance of insulation material factories and motor factories, some electromagnetic wire factories have successfully developed various types of mica wrapped wires with different structures. Currently, many motor factories are applying and promoting them.
Most of the faults and damages of rotating motors are caused by the damage of winding insulation. Among them, the inter-winding insulation accounts for about 50%. And once damaged, the consequences will be serious. Inter-winding insulation short circuit is basically caused by the inter-winding impulse voltage value of the motor exceeding the working voltage of the insulation of some windings under various overvoltage conditions. Some are caused by mechanical damage of the coils and windings during the manufacturing process, and others are caused by local discharge inside the high-voltage motor windings and corona corrosion of the high-voltage windings. The damages caused by these factors are all directly or indirectly related to the performance of the winding wires used in the motors. With the renewal and replacement of rotating motors and the need for various special motors and high-temperature-resistant motors, developing new types of winding wires is imperative.
Post time: Jan-05-2026