Study On The Influence Of Oscillating Voltage Exciting Times On Partial Discharge Characteristics Of Cable Defects And Cable Insulation Damage

At present,XLPE cables have been widely used in urban power grids.In recent years,methods for performing a partial discharge and a withstand voltage test to find a potential insulation defect of the cable have become the focus of the current power industry.Commonly used test voltage methods include power frequency voltage test method,DC voltage test method,very-low frequency voltage test method and oscillating voltage test method.Among these methods,the oscillating voltage test method has the advantages of light weight,small volume,convenient operation in the field and so on.It has become an important method for diagnosing the insulation state of cables.However,there is little systematic theory research at home and abroad on the relationship between the number of oscillating voltage exciting times and the partial discharge characteristics of cable defects and cable insulation damage.This paper conducts experimental research according to these questions.In order to study the relationship between the number of oscillating voltage exciting times and the partial discharge genaration of cable defects,the partial discharge test under the oscillating voltage was carried out with the tip defect as the test object.By analyzing the experimental data,the relationship between the number of oscillating voltage exciting times and the partial discharge generation of the defect was obtained,which provides a reliable guidance for the cable state diagnosis method under the oscillating voltage and the improvement of standards about the partial discharge test under the oscillating voltage.In order to study the relationship between the number of oscillating voltage exciting times and the partial discharge characteristics of cable defects,three kinds of defects were manually fabricated on the intermediate joint of 10 kV cable,and then the partial discharge test under oscillating voltage was carried out and the test data was recorded.By analyzing the test results,the relationship between the number of oscillating voltage exciting times and the partial discharge characteristics was obtained.It demonstrates the insulation damage of the oscillating voltage to the defective cable,and provides much experimental experience for the diagnosis of the cable insulation condition.In order to study the relationship between the number of oscillating voltage exciting times and cable insulation damage,the slice made of 10 kV XLPE cable main insulation material was used as the experimental research object,and then the breakdown voltage test under oscillating voltage was carried out.By repeating the test for several times,the relationship between the number of oscillating voltage exciting times and cable insulation damage was obtained,which provided effective guidances for the diagnosis of the actual cable insulation state and the development of standards about the solid slice breakdown test under the oscillating voltage.