New improvements in transmission switching using SF6 interrupter technology

The use of load break switches and sectionalizers to perform switching operations is common in the distribution circuits of electrical power systems. The functional need to isolate local regions of the transmission grid is expanding and, as a result, a new class of cost effective and reliable switching devices is needed. This paper discusses some applications where the capabilities of a transmission class switching device are employed. The SF₆ interrupter solves transmission class switching reliability concerns by utilizing a single break interrupter for voltages of 72.5 kV through 242 kV. The new design configuration increases the ampacity ratings available in cost effective transmission class switching devices. Several application descriptions and cost comparisons are included in the paper