The interruption of current in a network cannot meaningfully be considered in isolation from the operating voltage of the system and the nature of the system components and structure. The operating voltage itself affects the type of interrupter chosen for duty whilst the system components and structure (e.g. the extent to which the network is induct ive etc.) will influence the detailed design of the interrupter unit because of the voltage transients produced during the current interruption process. It is for these reasons that a discussion of current interruption in electric power systems is appropriate in a book on high voltage technology. The fundamental principles of current interruption as governed by high voltage considerations are therefore described with respect to both system based effects and the characteristics of circuit-breakers. Various types of SF₆ interrupters are considered and different factors which limit their performance are explained. Some possible trends in future developments are indicated.

Inspec keywords: SF6 insulation; interrupters; circuit breakers; power system transients

Other keywords: SF₆ interrupter; electric power system; high voltage technology; circuit-breaker; current interruption; voltage transient; gas filled interrupter

Subjects: Switchgear