Some Influence of Special Environment on Motor Insulation

Atmospheric pressure


In the plateau area (more than 1000 meters), the air density decreases with the increase of sea dial, which affects the increase of temperature rise and output of motor. The corona starting voltage of high voltage motor will also be reduced. If the motor runs with corona for a long time, it will affect the service life and safe operation of the motor.


In addition, the change of sea dial also has a great influence on DC commutation and brush wear. Under the atmospheric conditions of lack of moisture and oxygen (especially moisture), the formation rate of cuprous oxide film on the commutation surface slows down and can not be balanced with wear, which leads to the deterioration of commutation and the increase of brush wear.


High energy ray


High energy rays (such as electrons, protons or Y rays of nuclear radiation) can shift atoms of matter, produce lattice defects, form vacancy-gap atomic pairs, and damage the structure of matter by radiation. In addition, after being irradiated, the electron is detached from orbit, resulting in hole-electron pairs, which is easy to ionize the substance. The influence of radiation on insulating materials depends on the type and dose of radiation (expressed in dose rate or cumulative dose), the energy spectrum of radiation, the properties of insulation materials irradiated and the ambient temperature.


Radiation mainly causes damage to insulation materials, in which the mechanical properties of organic insulation materials are seriously damaged. Its allowable absorbed radiation dose is 10°rad, while inorganic insulation materials have better radiation resistance, such as quartz and mica, the allowable absorbed radiation dose can reach more than 10°rad.


Mechanical force


High pressure, impact and vibration load, easy to cause mechanical damage accidents of metal parts and insulation structure of motor.