Fuzzy probabilistic expert system for overhead conductor assessment and replacement

This paper introduces analytical models for accurate prediction of failure probabilities of existing conductors and recommends the optimum time window for conductor replacement at an acceptable failure threshold. The tensile failure probability is determined by solving the limit state equation of the corroded conductor subjected to environmental loading such as wind and ice using Monte Carlo simulations. The failure due to fretting fatigue caused by aeolian vibrations is accounted for using a fuzzy expert system. The results of the Monte Carlo simulations and the fuzzy expert system are then merged to determine the optimum time window for conductor replacement. Comparison of the model prediction and field data collected using LineVue™ show that the proposed models and expert system can accurately predict the replacement window of the conductors and shield wires.