Coordinated Use of TNA and Digital Computer for Switching-Surge Studies: Transient Equivalent of a Complex Network

On the basis of transient network analyzer (TNA) and digital computer tests, this paper discusses the possible correct evaluation of switching overvoltages by means of a coordinated use of analog and digital methods, taking into account both frequency- and voltage-dependent parameters. Special emphasis is placed on the transient equivalent of a complex network, its digital computation, and its representation on the TNA. Attention is focused on the range of frequencies involved in the transients following closing operations on lines of intermediate or long length.