Electrification of offshore petroleum installations with offshore wind integration E.Øyslebø/M.Korpås SINTEF Energy Research, N-7465 Trondheim eirik.veirod.oyslebo@sintef.no , Tlf: +47 73597191 Summary – This paper discusses transient stability issues related to combining offshore wind power with electrification of offshore petroleum installations. The study is based on a model that connects a petroleum installation cluster in the Norwegian part of the North Sea to the Norwegian power grid by using a VSC HVDC connection. Offshore wind power generation close to this petroleum cluster is investigated in the study. All parts of the modelled system are described in the paper, and several system topologies are discussed for use in the simulations part of the project. These simulations are mainly regarding transient stability of the offshore AC system, with focus on the quality of supply to the petroleum installations. Simulations show that faults on the offshore converter platform can be critical due to the dependency of the reactive power delivered by the HVDC-link to the offshore AC-system. However, it is shown that local wind power production matching the offshore power demand will improve both voltage and frequency stability. Further on, it is indicated that offshore reactive power injections or alternative wind farm control topologies could improve voltage stability offshore. The simulation work is done in the power system simulation software Simpow 11, developed by STRI AB. 1. Introduction Electricity to petroleum activities in the Norwegian part of the North Sea are mainly supplied by gas turbines located on the platforms. These turbines have a low efficiency ratio, and emit considerable amounts of CO 2 and nitrous oxides. An increased focus on climate change and emission reductions has made it interesting to address solutions for lowering these emissions from the Norwegian petroleum sector. One way to reduce the need for these turbines is to connect the petroleum installations to the Norwegian power grid. This paper will discuss issues regarding a petroleum installation cluster in the southern part of the North Sea with long life expectancy and high CO 2 and NO X emissions. The cluster is located 280 kilometers southwest of Norway, which means that it is well within the possible range of a VSC HVDC connection. This solution will however reduce, but not eliminate the CO 2 emissions from the petroleum sector. The reason for this is that Norwegian power production has a relatively high dependence of hydrologic conditions. In dry years there are high imports from fossil fueled power sources which increases the CO 2 emissions of the electricity production mix. An alternative for further emission reductions is to expand the system with offshore wind power production close to the oil and gas activities. The ocean depth and the wind conditions in this area could make such a wind farm both possible and favorable, both in terms of economy and emissions. This is the motivation for the current study, which investigates transient stability related to offshore wind and VSC HVDC in a situation where security of supply to the petroleum installations is highly valued. 2. Model data 2.1 Case study Today, the area in question consists of nine petroleum fields, which again include several installations. Five of these are not candidates for electrification due to low electricity demand and/or short remaining life expectancy of the activity on the field. The four remaining installations are suitable for further investigations. The total power demand is estimated to be