Air insulated compact substations

With the known greenhouse effect of SF6-insulated substations, the aim now is to reduce the size of transmission substations using air-insulated designs. In this work, a 400 kV compact substation layout is proposed adopting the lower IEC basic insulation level and switching impulse level, and consequently reduced clearances. Simulation studies using EMTP are performed to evaluate the lightning and switching performance of the proposed compact substation using different surge arrester locations and ratings. Further proposals for compaction are investigated through the introduction of innovative high voltage equipments. A preliminary evaluation of the percentage space saving achieved with some of the illustrated compact solutions is presented.