Electrical Performance of Fiberglass Davit Arms – Case Study with East Kentucky Power Cooperative

The utility industry has used fiberglass structures to improve grid reliability over the past 25 years. Fiberglass reinforced polymer (FRP) materials improve grid reliability by demonstrating high strength, consistent material properties, and can be constructed for resistance to environmental conditions such as ultraviolet exposure from natural sunlight[4]. More recently, utilities have begun to recognize there are also advantages to be gained in grid dependability by leveraging the electrical insulating benefits offered by fiberglass composite structures. This paper takes an in depth examination of multiple steel davit arm replacement projects at East Kentucky Power Cooperative (EKPC) where fiberglass davit arms were used to eliminate the occurrence of system operations on specific line segments. This paper will provide commentary on how and why fiberglass davit arms were used to solve issues in the field and improve line resiliency. This paper will also present experimental electrical testing data to support the conclusion that the utilization of fiberglass in transmission structures can improve - and in some cases double - the flashover performance of overhead transmission lines as compared to steel.