Electrical Strength of Long Gaps
This chapter considers an optimal rate of voltage rise, at which a gap will have a minimum electrical strength. It shows that conventional testing techniques have failed to separate the parameter deviation of a voltage pulse from that of gas discharge processes that form a leader. The dependence of the gap strength on the rise time of the applied voltage pulse is quite appreciable in gaps with strongly nonuniform fields. In the case of a strongly nonuniform gap with a supercritical anode radius, the breakdown voltage depends on voltages necessary for both the corona initiation and leader inception. Thus, electrical strength of a long gap with a strongly nonuniform field and a small anode is largely determined by the voltage necessary for the gap overlap. If the voltage pulses have a short rise time, the strength is also affected by the leader inception conditions.