Ormen Lange Long Step-out Power Supply

Abstract

This paper gives an overview of the Ormen Lange LongStep-out Power Supply (LSPS) system which shall provide power and communication over the 120 km step out distance from Nyhamna west coast of Norway to the subsea gas compression station. The document will present status including technical description and qualification programmes. Transmitting 65 MW over a distance of 120 km is challenging not only related to voltage and power loss at full load, but also to the voltage stability at number of different load scenarios, such as reactive power production in the cable which is also present in no load situation. The subsea mounted Variable Speed Drive (VSD) dictates stringent requirements to voltage variation and stability of the power supply system. Limited track record and maturity of components and equipment meant that development and qualification testing would be necessary to ensure sufficient reliability of the subsea power supply system. On this basis StatoilHydro decided to include the LSPS system in the pilot testing of the subsea gas compression at Nyhamna west coast of Norway. The LSPS pilot project was kicked off in July 2006. Since then development and testing of LSPS equipment and components has been ongoing. The status of the Long Step-out Power Supply project is that all the qualification programs have been successfully completed together with most of the manufacturing for the pilot LSPS. System test for the LSPS pilot system is scheduled to take place during October 2009. Hook up and mechanical completion at the Nyhamna test site is scheduled for first quarter of 2010.The purpose of the LSPS pilot system is to test and qualify components and equipment to be used in the LSPS permanent system as far as practical.