GB1120107A - High voltage substation - Google Patents

Abstract

1,120,107. High voltage substation layouts. WESTINGHOUSE ELECTRIC CORP. 15 July, 1966 [26 July, 1965], No. 31806/66. Heading H2H. A space-saving sectionalized high voltage substation comprises a multi-level structure housing the electrical equipment which is connected by conductors enclosed in grounded conducting pipes containing a gas of high dielectric strength, the sectionalization allowing the substation to be factory built in predetermined units and then connected together. As shown, a three level structure comprising support members 32, 33, 34 houses a transformer 17 in the first (ground) level and circuitbreakers in the second and third levels, these circuit-breakers and their ancillary equipment, e.g. members 14, 15, 18, 36, 37, 38 being arranged in U or rectangular formation to further reduce the amount of space required for the substation. The breakers are of the dead tank type containing an electronegative gas, e.g. sulphur hexafluoride, which also fills the metal housings containing the conventional lightning arrestors 21, 22 and coupling capacitors 23. This gas also fills the conducting pipes containing the (hollow) interconnecting conductors, although carbon dioxide, nitrogen, air or mixtures of these latter gases may be used instead. The pipes may be of metal or insulating material with a return (earthed) line, e.g. a plastics pipe whose outside is coated with a conducting or semi-conducting material. The pipe sections are joined and sealed with specially-shaped connecting pieces, Figs. 12, 13 and 14 (not shown). During erection or maintenance, the conductor and pipe may be terminated by members shaped to minimize voltage gradients, Fig. 11 (not shown). The conductor is mounted centrally in the pipe by spaced insulators, and arrangements are described to reduce electrical stress at the junctions between the conductor and insulator and the insulator and pipe, Figs. 9 and 10 (not shown). Sealing between the transformer bushing and the pipe is also described, Fig. 8 (not shown). The breakers and bus runs may contain different gases at different pressures.