T/CES 108-2022 Double-gap isolation switch used in gas-insulated metal-enclosed switchgear

Scope

Scope: This document specifies the normal and special operating conditions, rated values, design and structure, type tests, factory tests, and selection guidelines for double-break disconnecting switches used in gas-insulated metal-enclosed switchgear (GIS). This document applies to GIS with voltages of 72.5 kV and above, a rated frequency of 50 Hz, and is suitable for indoor and outdoor applications, three-phase shared-box and three-phase split-box configurations, using sulfur hexafluoride gas as the insulating medium. Main technical content: When expanding, installing, conducting voltage withstand tests, or performing maintenance on gas-insulated metal-enclosed switchgear (GIS), it is necessary to consider the shutdown of the busbar. Prolonged power outages will affect the operation mode of the power grid. To address the problem of power outages during GIS expansion and maintenance tests, this document proposes a disconnecting switch structure with dual isolation breaks and auxiliary grounding switches, which enables uninterrupted operation of the GIS busbar, busbar outlet extensions, voltage withstand tests, and maintenance during these operations. The structure of the double-break disconnecting switch and auxiliary grounding switch differs from the conventional single-break isolation structure in terms of structural design, technical parameters, test items, operating procedures, and implementation of the non-power-outage function. Currently, no relevant standards for double-break disconnecting switches exist for GIS. Therefore, to provide technical requirements for this type of GIS double-break disconnecting switch, this standard has been developed. This document specifies the rated values, structure and design, type tests, factory tests, and selection guidelines for double-break disconnecting switches used in GIS.

Development Information

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