Added critical flashover voltage by fiberglass crossarm to 15 kV polymer suspension insulator

The paper is based on the investigative studies performed on the fiberglass crossarm which will be generally used in the distribution line structures as an additional insulation component. Lightning impulse voltage tests were conducted on the fiberglass crossarm alone to determine its critical flashover (CFO) voltage, and also the critical flashover voltage of 15 kV polymer suspension insulator plus the fiberglass crossarm. The added CFO voltage of the fiberglass crossarm to the insulator was determined with polymer suspension insulator as the primary insulation component and the fiberglass crossarm as the secondary insulation component. The added CFO voltage was evaluated for 1 ft through 5 ft length of the fiberglass crossarm for both positive and negative polarity, under dry and wet condition. All these tests were conducted in the High Voltage Laboratory at Mississippi State University. A comparison of the CFO and added CFO voltages by the fiberglass crossarm to the polymer suspension insulator with the CFO and added CFO voltages of wood crossarm to the polymer suspension insulator is presented.