Impact of improved models on the reliability calculation of offshore wind farms

Reliability calculation programs for electrical power systems are available since the early 80s and have been since then continuously developed e.g. [1] [2]. However, these programs are designed for conventional power supply systems which consist of predominantly consumers. Through the development of electrical power systems in Europe and particularly the establishment of many new offshore wind farms, these lead to an enormous change in the power supply grids (infeed grids). Therefore it is a substantial need for adaptation of these programs to determine the reliability of the overall power system in a realistic way. In this paper, additionally to the offshore specific reliability indices, three new models are presented. These models are especially created for offshore wind farms and their characteristics. These models are respectively: the weather influence model, the power infeed control model and the reliability modeling of the wind turbine generator (WTG). Based on one exemplary wind farm design, the developed models are compared with the conventional models. This work presents the impact of the different improved models on the reliability results. The importance and the necessity of these established models in order to reach more realistic and environmental depended reliability analysis results are hereby illustrated.