Title :
Resolution evaluation of ultrasonic diagnosis tools for electrical insulation devices and the detection of electrical trees
Author :
Ueno, H. ; Walter, P. ; Cornelissen, C. ; Schnettler, A.
Author_Institution :
Inst. for High Voltage Technol., RWTH Aachen Univ.
Abstract :
Ultrasound is a well-known diagnosis tool that can be used for the condition assessment of insulating systems. For this special purpose, various investigations on the detectability of the included inhomogeneities are performed: The resolution of ultrasonic measurements on high voltage insulations has been evaluated by using standardized Landolt rings in silicone rubber and epoxy resin. Although a dependency exists on the ring position, the diagnostic system that is used is able to image the gap with a sub-millimeter size. In other words, the system has recognition ability for two different objects close to such a distance. Regarding detectability, it has been found that in addition to ball-shaped inhomogeneities, the system can also detect thin fibrous objects with a diameter of a few micrometers. Finally, the results are used to detect and characterize electrical trees in silicone rubber
Keywords :
condition monitoring; epoxy insulation; silicone rubber; trees (electrical); ultrasonic measurement; condition assessment; electrical insulation devices; electrical trees detection; epoxy resin; inhomogeneities detection; silicone rubber; standardized Landolt rings; thin fibrous objects; ultrasonic diagnosis tools; ultrasonic measurements; Dielectrics and electrical insulation; Frequency; Partial discharges; Pollution measurement; Power transformer insulation; Rubber; Trees - insulation; Ultrasonic imaging; Ultrasonic variables measurement; Voltage;
Journal_Title :
Dielectrics and Electrical Insulation, IEEE Transactions on
DOI :
10.1109/TDEI.2007.302893