Fewer interruption minutes thanks to preventive system
DNV’s Smart Cable Guard can detect beginning malfunctions in medium-voltage cables, and can indicate where they will occur. If the malfunction cannot be fixed, the system is able to identify and localize the short circuit. Smart Cable Guard 2.0 has been newly designed by Technolution Spark.
How does Smart Cable Guard work?
A Smart Cable Guard sensor and control unit is placed at either end of a medium-voltage cable. As soon as a malfunction threatens to occur in the cable, for instance due to degradation or external pressure from tree roots or soil subsidence, this generates certain discharges. These partial discharges cause small pulses in the cable which Smart Cable Guard is able to measure. The pulses arrive at the two Smart Cable Guard units at different times. Thanks to precise time synchronization, the system can then determine the location of the partial discharge in the cable within a margin of less than one percent of the cable length. This means Smart Cable Guard can give a precise localization of the malfunction that is about to happen.
The system helps grid operators to reduce the number of interruption minutes. Society is strongly dependent on electricity and this dependency is only increasing. The medium-voltage grid consists for a large part of decades-old cables that are not always designed to deal with the peak loads that common nowadays. Because Smart Cable Guard can reliably predict malfunctions, and can moreover indicate the location of the problem, it becomes possible to prevent malfunctions by taking timely action. Maintenance thus becomes a planned process and impromptu repairs are reduced to a minimum.
Further development of a successful concept
Smart Cable Guard is the result of a research trajectory that brought together not only DNV but also Eindhoven University of Technology, Alliander, Enexis, Stedin and others. When it came to developing Smart Cable Guard 2.0, Technolution found in DNV an industrialization and engineering partner with extensive knowledge of digital and analog electronics, software and the underlying principles of physics. The new version of the system realizes greater cost reduction and enhanced reliability and sensitivity. In addition, Smart Cable Guard 2.0 is suitable for remote maintenance.
“The new version is has a greater sensitivity and costs only a third of the original Smart Cable Guard.”
Denny Harmsen, innovation consultant at Alliander, has been working together with DNV on developing an integrated solution for quality control for the medium-voltage grid since 2001. For Alliander the cost price of the original Smart Cable Guard was an obstacle. “The system had a lot of benefits for us, but the price was too high if you look at the components. The new version is has a greater sensitivity and costs only a third of the original Smart Cable Guard.” Harmsen is impressed by the speed with which the system was developed by Technolution. “This company is more than just a fine skyscraper in Gouda; they are very strong on hardware”.
