The need for European Network Codes (NCs) was identified during the course of developing the third legislative package for an internal EU gas and electricity market. The first NC that was initiated by the European Commission covers `Requirements for Generators’ (NC RfG) (ENTSO-E, 2013). After an extensive debate and drafting process across TSOs, DSOs, manufacturers, generation owners, industrial consumers, NRAs and policy makers, ENTSO-E finalised drafting the NC RfG in March 2013 (Further changes, especially with respect to the fault-current injection by wind power plant (WPP) were introduced during the process of transferring NC RfG to a EU Regulation as result of the ongoing discussions between the European Commission and relevant stakeholders. See the remark in Section 3 `Outlook and Conclusion’.). European wind turbine manufacturers represented by EWEA participated strongly in the dialog with ENTSO-E and the stakeholder consultation.
A delicate exercise in developing the NC RfG was the appropriate balance between those aspects that need to be defined exhaustively at European level, and the non-exhaustive connection requirements where further specifications are needed at regional level to cover local system needs. Although improvements were seen, significant concerns still remain with the current document, largely focused on the uncertainty from the many non-exhaustive requirements and therefore having to wait for the national Grid Code processes for many parameters. This study explores the need for fault-ride-through capability from a power system security point of view. The requirements stated in the NC RfG, capabilities of WPPs and challenges related to the non-exhaustive requirements of the NC RfG are presented and discussed with the intention to provide technical background information, which may support the national implementation of these requirements.