The Surge Protection of an SF6 GAS-Insulated Substation Supplied by Pipe-Type Cables

It is shown that station entrance surge arresters are not required to maintain adequate protective margins in a proposed SF6 substation connected by HPOF pipe-type cables. This results in substantial cost savings for this installation. A calculation procedure is presented for predicting the maximum rate-of- rise of incoming lightning surges, enabling engineers to assess the feasibility of eliminating station entrance arresters in similar substations. The calculated results are confirmed by simulations with a digital transients computer program and a Transient Network Analyzer (TNA).