Analysis And Research On The Insulation Damage Of Dry-type Air-core Reactors Under The Action Of Temperature And Humidity

Reactors have a variety of functions.The main types of dry-type air-core reactors are current-limiting,parallel-connected,and filtered dry-type air-core reactors.Due to the rapid development of the national economy,the load demand of the power grid system is increasing day by day,and the reactor is put into use more and more.Since the outdoor reactor was put into use in the 1980 s,the reactor has been damaged by various internal and external factors.Accidents are not uncommon,so high-quality,high-reliability reactors are important for ensuring the normal and effective protection of the power grid.Damage to equipment can seriously affect the safe operation of the power grid system.This paper inverts the damage of the dry-type air-core reactor through the damage data of the historical reactor.(1)This article analyzes the fault accidents in the literature that are available in recent years,classifies the fault types,and finds that the short-circuit and local overheating are the main manifestations of the accident.The temperature field of the dry type air-core reactor was simulated and analyzed to show the distribution of different temperature envelopes,and the damaged parts of the collected data were counted.According to the analysis of the main technical indexes of dry-type air-core reactors by the cause of the accident,it is found that the effect of temperature on the encapsulated insulating material epoxy resin is an important cause of the safe operation of the encapsulation;(2)Since the reactor generates a large amount of heat during operation,when a certain temperature is reached(a temperature close to the corresponding calorie level)according to the existing method,simple ones and zeros are used around the temperature of the specified calorie level.This indicates that the degree of membership is too absolute.This paper uses fuzzy mathematics to analyze the reliability of the enveloper's encapsulation,and the membership function of the encapsulated temperature variable about the normal operation of the enclosed circuit's normal operation.The distribution function of the encapsulation temperature is toobtain the fuzzy reliability of the encapsulation of the temperature increase factor;(3)According to the statistics of the 40 fault data,10 faults occur when the humidity air is relatively large.When the relative humidity in the air is relatively high(rain,snow,fog,etc.),the humidity and temperature will work together.Insulation composites cause hygrothermal aging phenomena.By using the Arrhenius extrapolation model to predict the service life of the encapsulation,the aging life of the epoxy resin at a temperature of more than 70% at different temperatures was obtained(the 70% strength The retention rate applies to the critical strength required for ordinary non-structural materials.);(4)Because the change of the mechanical properties of the insulating material will affect the morphological change of the material,when the tensile strength is insufficient and the wire breaks easily under the action of the electrokinetic force,and the contact between the moisture and the wire reduces the safety,this article according to the retention of mechanical strength at different temperatures.The rate is negatively correlated with the moisture absorption rate of the material,and the mechanical strength of the insulator decreases with the increase of the moisture absorption rate of the material,and cracks are more likely to occur under the action of the electric field of the electric field and creepage phenomenon occurs,thereby threatening the safety of the reactor.