High Voltage AC and DC Subsea Cables for Offshore Wind Farms and Transmission Grids

Within Energi 21 (a unifying R&D strategy for the energy sector) five technology target areas are identified in order to respond to the key challenges and to the national objectives. In the strategy document for Energi 21, one of the target areas for more intensive basic research is an energy system for the need of the future. The main priorities within this target area are related to cabling from offshore wind mill farms either to mainland Norway or to other countries by subsea cables. Reliable subsea powerAC and DC cables are of crucial importance if an offshore transmission network shall be established. Dynamic cables installed on deep waters are not a proven technology; this will be important components for offshore wind farms in the future. This c alls for technology improvements, where the knowledge about limitations for the long term performance of high voltage power cables are important design criteria. The research within this Renergi KMB project will have a generic approach in order to provide knowledge for technical improvements and consequently long and reliable service performance of high voltage subsea AC and DC cable systems. Five main research tasks are defined within the project: T1: Impact of dynamic mechanical loads and hydrostatic pressure on AC polymeric cable systems T2: Long term properties of subsea DC cable systems T3: Development of sensitive Qualification Test Methods for very long AC and DC subsea polymeric cables T4: Development of test facilities for combined dynamic / electric testing T5: Develop methods for condition assessment of long subsea AC and DC polymeric cables There will be one Ph D student and one Post Doc at NTNU working with selected activities within Task T1 or T2.