Belgian experience with real time thermal rating system in combination with distributed temperature sensing techniques

摘要

The required permanent load of a HV cable system is an important parameter to select the right cross section and define the appropriate laying conditions. However the overload capabilities of a HV cable circuit are seldom used to avoid the risk to overheat the cable system and influence the lifetime of the system. With the use of a real time thermal rating (RTTR) system Elia wants to overload a strategic 150 kV link on a safe and controlled way. The first RTTR system of Elia was installed end 2014 on a 33 km long cable link 150 kV - 2000 mm~2 Alu between Koksijde and Slijkens. During the preparation and after the installation of the DTS/RTTR system several problems were tackled: communication and IT related problems, calibration problems of the DTS, adjustments of the thermal model of the RTTR,.... The key factor to success for an efficient integration in the Elia grid is the early involvement and collaboration between different experts: IT, cable and data communication. In order to improve the accuracy of the entire RTTR system several actions should be taken and planned after the installation: adjustment of the thermal zones, verification of communication paths, analysis of the calculated fibre temperature, different hot-spot analysis. This paper explains the experience of Elia with the installation of the RTTR system, focusing on typical problems and provides final recommendations about the integration and overload capability of the 150 kV link with a DTS and RTTR system.