Compact footprint and minimum environmental impact key attributes of latest 245 kV GIS
ABB launches its latest generation 245kV (kilovolt) ELK-14 series of Gas Insulated Switchgear (GIS). The footprint of this latest GIS is 40 per cent less than conventional designs and it uses 20 per cent less SF6 gas compared to the previous generation, making it even more environmentally friendly than its predecessor.
Its compact design also enables the unit to be delivered as a completely assembled bay, reducing installation time by more than 60 per cent compared to traditional construction. The bays feature single-phase isolation, and are delivered fully tested and mounted on a frame. The intelligent control and protection equipment installed in the control cubicle directly at the bay is also a smart grid enabling feature.
The bay arrangement is highly flexible, so that all system configurations, including subsequent expansions, can be easily and quickly implemented. The systems have been designed for a rated voltage of 253 kV, and can handle rated currents of up to 3,150 A (Amperes). The versions conforming to the IEC and IEEE standards have been designed to protect power networks up to a rated short-circuit (fault) current of up to 50 kA (kiloamperes). The new ELK-14 design also facilitates more convenient accessibility to the operating mechanisms located in the front of the bay and positioning of the current transformers outside the gas compartments.
ABB is the global leader in high-voltage GIS technology, with more than 20,000 bays installed and operating reliably around the world. ABB pioneered high-voltage GIS in the mid 1960’s and continues to drive technology and innovation. In 2009, ABB commissioned a GIS rated to handle more than one million volts (1,100kV), with a switching capability of 6,900 megawatts, reaching new heights in terms of global voltage levels.
GIS technology is a compact, modular and robust solution for maintaining reliable electrical power under challenging conditions with minimum maintenance needs. Other key benefits include low technical losses and enhanced equipment security. The technology’s minimized footprint enables installation in locations with space constraints, such as busy city centers and even indoors. ABB’s product range also includes GIS for offshore and mobile applications.
SF6 (sulfur hexafluoride) gas is extensively used in the electrical industry for dielectric insulation and current interruption in high-voltage circuit breakers, switchgear, and other electrical equipment. SF6 gas under pressure is used in gas insulated switchgear (GIS) because it is much more dielectric (non-conductive) than air or dry nitrogen, making it possible to significantly reduce the footprint and enable installation in constrained spaces.