Overview
Each year, more than one thousand short circuits are occurring in the network of OEBB. This results in high maintenance and associated costs. At the present time, technology in substations is in place which is capable of detecting the occurrence of short circuits, but a proper localization is not possible. By the use of Distributed Acoustic Sensing (DAS) Technology, which is based on Optical Time Domain Reflectometry (OTDR) measurement, the supervision for acoustic and seismic events near a fibre-optic cable (at a distance of up to 80 km via the DAS system) is possible. As short circuits generate acoustic and seismic vibration, DAS provides the ideal basis for detection and localization of same.
DAS basic technology is integrated into the platform of Frauscher Tracking Solutions (FTS). The capability of detection is dependent on several factors, such as the installation of the fibre, the intensity of the short circuits, the distance between the fibre and the overhead line, etc. These factors result in the research questions as listed below:
- What is the required intensity of a short circuit?
- Which installation method is best to achieve the most proper localization of short circuits? Are any disturbing ambient noises and what is the influence of those on the detection of short circuits?
- Which limitations are due to the interaction of the influencing factors mentioned above?
Because testing and evaluation of the recorded raw data are extremely difficult and time consuming, an algorithm for a proper and automated detection and localization of the present has been developed. As it is exactly localized, this technology is very innovative. The technology is used for short circuit detection. The developed algorithms and the findings of this research may be used in the future.