Power Quality Problems Caused by Termites on 138-kV Underground Cables

This paper discusses problems found in the operation of underground cables in the transmission system of CEMIG, with emphasis on insulation failures caused by termites. This problem has been the source of many scheduled and non-scheduled interruptions in later years, leading to significant maintenance costs. Experience with current practices designed to detect and prevent this failure mode is described. It is argued that new procedures are needed for improved on-line, pre-failure detection. Test improvement will hopefully contribute to increase the lifetime of underground cables currently in use, as well as to reduce maintenance costs

This paper discusses problems found in the operation of underground cables in the transmission system of CEMIG, with emphasis on insulation failures caused by termites. This problem has been the source of many scheduled and non-scheduled interruptions in later years, leading to significant maintenance costs. Experience with current practices designed to detect and prevent this failure mode is described. It is argued that new procedures are needed for improved on-line, pre-failure detection. Test improvement will hopefully contribute to increase the lifetime of underground cables currently in use, as well as to reduce maintenance costs.