Evaluation of insulation of H.V. Bushing#x2014;Online monitoring tg#x03B4; of a 500kV bushing

摘要

This paper represents a series of online monitoring data from a 500kV bushing on a converter station's transformer. An online monitoring system with a novel tgd measuring method has been successfully used for bushing tgd supervision. Long term data acquisition is evaluated for the insulation integrity of the bushing. It shows that bushing tgδ depends on its temperature/voltage intersect influence during operation. The largest bushing tgd occurred at the highest voltage and the lower temperatures. A further study of the temperature/voltage intersect influence on bushings need to be scheduled.