Traveling waves initiated by switching

THE dominating position of the lightning surge as the principal scourge of transmission lines has occupied so much attention in the technical literature that traveling waves developed from other causes have been relegated to a zone of comparative unimportance. But lately, a growing interest and curiosity concerning switching surges makes it imperative to investigate, theoretically, the possibility of initiating traveling waves from the steady state; for both the “energizing” and “de-energizing” transients associated with switching operations are calculable as traveling waves and their successive reflections. The object of this paper, therefore, is to lay the groundwork for a systematic treatment of switching surges by considering the general subject of the initiation of traveling waves from steady-state conditions. In general, such waves are started either by closing or opening a switch; and the corresponding transients may be called closing transients and opening transients, respectively. If a “dead” line is connected to a generator, the ensuing transient is called an energizing surge, while if a “live” line is disconnected from a generator the transient is called a de-energizing surge.