Grid Connection of Large Wind Power Plants - a European Overview

Due to their increasing size, more and more wind farms are being connected at the transmission network level. As a result of this development, in many European countries guidelines for the connection of wind power plants to the transmission networks have been already adopted. Generally, these guidelines are included in the so-called Grid Codes, but they can also be found in national legislations. Grid connection procedures are accompanied by grid connection costs that may include all or a part of the necessary transmission expansion costs. Hence, the connection of new wind farms is also influenced by the way the grid connection costs are shared between the involved parties. This overview paper investigates the above mentioned issues, targeting the current situation in the European countries. Firstly, a comparison of the most common technical requirements for wind farm connection to the transmission networks is made, focusing on important features, such as: system voltage and frequency operating ranges, active power control, reactive power control, fault-ride-through capabilities and voltage support during grid faults. Secondly, the wind connection charging methods and policies adopted by the European Union countries are compared. This assessment provides an update on the degree of fragmentation and inconsistency of the technical and regulatory rules adopted for wind power connection in Europe, and also serves to emphasize the need for future harmonized approaches for the effective wind integration in the European liberalized power system. Moreover, the technical requirements survey gathers important information needed for ongoing work in wind turbine modeling. The main contributions of this paper are a systematic and easy-to-visualize comparison of the latest grid connection requirements for a large number of European countries, as well as an analysis of grid connection charging methods and policies for all the 27 European Union countries.JRC.F.3-Energy securit