On-line detection and location of low-level arcing in dry-type transformers

This paper describes the development of a microprocessor based system, based on four different physical phenomena, for reliable and accurate detection and location of arcing in dry-type transformers. The proposed technique was tested for actual arcing, generated on a 15-kVA, 230/115-V Y/[DELTA] transformer enclosed in a 30' X 30' X 21' metallic enclosure. Some results showing the performance of the detection and location system are presented in the paper. The technique can be applied to detect arcing in metal-clad low-voltage/medium voltage switchgear, drives, gas insulated switchgear (GIS), generator bus-ducts, and other metal-clad electrical apparatus against arcing. Index Terms--Dry-type transformers, low-level arcing, on-line monitoring.