Evaluation of Aging State of Composite Insulators Based on Terahertz Method

Composite insulator is an important insulating equipment of power system, which is prone to internal faults that are not easy to detect during operation, and the detection and diagnosis of faults becomes an important issue. Terahertz method is an emerging method to detect internal faults of insulators, which has the advantages of strong penetration ability, high safety and accurate measurement, and can effectively extract the information of the measured samples and precisely determine the fault location of insulators. In this paper, firstly, samples of six composite insulators with different operating ages in a region of North China were made, and afterwards, in order to investigate the influence of aging degrees of composite insulators on the terahertz wave transmission parameters, the terahertz vector network analyzer was used to conduct experimental tests on the calibrated groups of samples\, and a model of aging detection of composite insulators based on the terahertz signal transmission characteristics was established.