Evaluation of Hurricane Impact on Failure Rate of Transmission Lines Using Fuzzy Expert System

Adverse weather, such as hurricanes, can have severe effects on power system reliability. Incorporating weather effects in power system reliability evaluation has drawn more and more attention in recent years. In past decades, many methods have been proposed to evaluate power system reliability considering weather effects. Some of the earliest methods used the two-state weather model. These have been later expanded into multi-state weather model, regional weather model (RWM) and statistical regression method. In this paper, a fuzzy expert system (FES) is proposed and is combined with RWM to assess hurricane impact on the reliability parameters of transmission lines. Firstly, according to the computation requirements the composite system is partitioned into different regions. Then, the FES maps the nonlinear relationship between the hurricane parameters (indicator of hurricane severity) and the increment multipliers of failure rates (IMFR) of the transmission lines in different regions. In this step, the possible case that transmission lines traverse adjacent regions is investigated by using weighted average method (WAM). Finally, the results obtained by using the proposed method can be used in analytical or simulation method to evaluate composite system reliability considering hurricane impact. The proposed method is applied to the IEEE reliability test system (RTS). The implementation demonstrates that the proposed method is effective and efficient and the FES is convenient to construct.