Research On Live Detection System Of Composite Insulator Based On Ultrasonic Phased Array

Composite insulator has good hydrophobicity and hydrophobicity migration,especially excellent anti-pollution performance,which provides an effective method to eliminate the large area pollution flashover of transmission line insulator With the increase of running years and the impact of adverse environment,a series of defects appear in the operation of composite insulator.In this paper,a live detection method for the internal defects of composite insulator based on ultrasonic phased array is proposed,and the method is used to detect the electrification of the composite insulator The method uses the same method of the human body and the earth voltage to detect the live line,avoids the influence of the power failure operation on the power system.Adopts ultrasonic phased array sector scanning mode to detect the different types of composite insulator defects,and analyzes the internal defects of the insulator through the scanning results.The main research contents are as follows:(1)In order to achieve the requirements of live detection of composite insulator of transmission line,a kind of ultrasonic water-pocket coupling device is designed.The flexible coupling of the device realizes the appropriate coupling of the probe and insulator,and solves the problem of ultrasonic coupling in on-line detection.(2)Manufacturing the artificial defects of the composite insulator.the traditional water immersion method and the water bag method are used to detect the composite insulator with intact and defective.The detection results are basically consistent,and the feasibility of detecting the composite insulator by the water bag flexible coupling device is verified.(3)Using the direct contact method of the probe to detect the defects of planar silicone rubber with a certain thickness,the ultrasonic phased array is detected by different scanning methods,the detection results show that the linear scanning effect is better than the sector scanning,and provides a new method for the detection of composite insulator umbrella cover.(4)Using the water-pocket flexible coupling device to conduct phased array sector scanning for the defects of the insulator sheath,impurities,and other kinds of artificial internal defects.The detection results can clearly show the existence of defects.The detection results can clearly show the existence of defects,in addition,the sheath0.8mm,1.0mm,1.5mm different size of the defects were detected by this method of detection.(5)The air holes with different sizes of 1.1mm and 1.5mm were tested by the flexible coupling device of water-pocket.In addition,phased array sector scanning detection is performed with different phased array probe frequency.With the flexible coupling of water-pocket,the ultrasonic phased array detection of composite insulator sheath,different types of mandrel and different size defects is carried out.Through the analysis of the experimental results,the feasibility of the coupling device used in ultrasonic equipment to detect the defects of composite insulator is verified,which provides a new idea for the online detection of composite insulator defects of transmission line.