Electricity and Control September 2021

TRANSFORMERS, SUBSTATIONS + CABLES : PRODUCTS + SERVICES

Acoustic imaging can detect hidden risks

The new Fluke ii910 Precision Acoustic Imager detects co- rona, partial discharge, and gas, steam and compressed air leaks which can impact negatively on production up- time and the bottom line. Although most manufacturers know these types of leaks exist, until now they have generally been seen as too time-consuming or tedious to address. Comtest, local rep- resentative for Fluke, reports that with the new Fluke ii900 or ii910 and minimal training, maintenance technicians can begin checking for leaks during typical maintenance rou- tines – even during peak operating hours. The ii900 series acoustic imagers let technicians ‘see’ sound as they scan hoses, fittings and connections for leaks. An array of tiny, sensitive microphones, built into the acoustic imagers, generates a spectrum of decibel levels per frequency. Based on this output, an algorithm calculates a sound image, known as SoundMap™, which is superimposed on a visual image. The SoundMap is automatically adapted, depending on the frequency level selected, so that background noise is filtered out, making it simple to detect compressed gas leaks. Thus the ii900 series provides an easier way to detect compressed air, gas, steam and vacuum leaks. And the ii910 provides increased sensitivity to detect leaks that are smaller or further away. Detecting partial discharge Partial discharge is a serious concern that needs to be monitored, ideally in a quick and easy way. Whether inspecting insulators, transformers, switchgear or high Nexans has achieved electrical type testing of a 525 kV dc gas insulated switchgear (GIS) sealing end, according to CIGRE TB 496, with the cooperation of Siemens Energy. In the high voltage direct current (HVDC) market, cables with an insulation composed of cross-linked polyethylene (XLPE) have emerged in the past ten years and allowed for the deployment of innovative electrical grids in Europe and worldwide. Nexans’ ecosystem encompasses best-in- class partners who share its values, working together to deepen its ability to stay a step ahead of what the market needs. GIS type ends constitute an interesting component in

The Fluke ii910 Precision Acoustic Imager is designed for use by electrical maintenance teams working on high voltage equipment. voltage power lines, technicians need to be sure that a problem can be spotted quickly. Partial discharge that goes unchecked can cause blackouts, fires, explosions, or, in some instances, death from arc flashes. In addition to the danger that partial discharge poses to human lives and the environment, there is a significant monetary risk of downtime. When critical equipment goes down it can cost millions of rand per hour in lost production time. The Fluke ii910 Precision Acoustic Imager is specifically designed for use by electricians and electrical test engi- neers working on high voltage equipment, and grid mainte- nance teams that are constantly inspecting and maintaining power distribution and industrial high voltage equipment. The ii910 provides a safe, quick and easy way to detect and locate partial discharge in order to maintain high volt- age equipment and prevent catastrophic events. With the SoundSight™ technology the ii910 translates the sounds that it hears into a visual representation so problem areas Nexans developed a dedicated GIS cable sealing end for a 525 kV dc XLPE cable system. The studies on electro-thermal aspects of the interface resulted in an optimised accessory design. The solution consists of a Nexans GIS termination plugged into a Siemens Energy dc GIS enclosure, both compliant with IEC 62271‑209 standards dimensions. The validation of the solution has been completed successfully through an electrical 525 kV dc VSC Type Test according to CIGRE TB 496. The test was per- formed in Nexans’ Calais high voltage laboratory un- der the certification of an independent third party. This technological breakthrough enables Nexans to offer competitive products for the deployment of HVDC links with direct connection to dc GIS. The Nexans Group strives to create a new world of electrification: safer, sustainable, renewable, decar- bonised and accessible to everyone – connecting us all to new opportunities, technologies and behaviours that will build a better future.

Successful type test for 525 kV dc GIS cable sealing end

Nexans has developed a dedicated GIS cable sealing end for XLPE cable systems used in HVDC projects.

the HVDC links due to the flexibility and compaction they allow in the connection of cables of different structures, especially in congest- ed spaces such as on an offshore platform. They are also suitable for use in back-to-back mode, thus constituting a mixed joint (for ex- ample, between cables of different technologies).

For more information visit: www.nexans.com

24 Electricity + Control SEPTEMBER 2021