Application of rotating arc SF6 interrupter design to the highest distribution voltage levels

The introduction of third generation SF₆ interrupter technology has done much to enhance the performance and reliability of switching devices used at the highest distribution voltages and throughout the transmission voltage range. Auto expansion circuit breakers where significantly less energy is required from the mechanism are now common place. Development activity is now being directed to the next generation of interrupter devices which will utilise rotating arc SF₆ interrupters. These devices offering the user even more advantages than the currently applied technologies. Two techniques have been utilised: (1) incorporating a secondary field using permanent magnets; and (2) incorporating a small puffer unit into the design which would produce sufficient quantities of clean gas to interrupt small currents