Results for long term performance tests on polymer insulated cables up to 230 kV

Accelerated cable life testing is of great importance for polymer insulation to estimate expected cable life under operating conditions. The status of long term performance tests on HV polymer insulated cables with maximum field strength of 15 kV/mm is reported. Some 60 and 110 kV cables have been subjected to cyclic loading with more than two times nominal voltage for seven years. Extrapolation from results after three years accelerated aging indicates a cable life far above the expected 40 years