Tools for handling high amounts of wind generation in National Control Centre in Ireland

EirGrid Group which comprises the TSOs for Ireland and Northern Ireland and the single electricity market operator operates a synchronous system with a total generation installed capacity of 11.5 GW of which 17% is wind. With 12% of annual electricity output from wind, the instantaneous wind generation frequently reaches 50% of the total generation. This figure is set to increase as both Ireland and Northern Ireland have set a target that requires 40% of generation by 2020 to come from renewable energy sources, with the majority of this from wind (37%). In order to maximise wind generation while maintaining the reliable and secure operation of the system, a number of online tools to help Grid Controllers handle wind have been introduced in the EirGrid National Control Centre (NCC) in addition to the guidelines based on off-line studies and analyses. One such tool is the Wind Secure Level Assessment Tool (WSAT). WSAT calculates the Secure Wind Level (SWL) on the system on-line by modeling thousands of static and dynamic contingencies using real-time network topology and operating conditions as a starting point. At present SWL is defined by the voltage stability limit of the system assessed through analysis of a transfer between wind and conventional generation. In future SWL will also take account of thermal, transient, and frequency stability of the system with changing wind penetration. Another tool that EirGrid is considering is a Generator Ramping Tool (GRT) that will be estimating the ramping requirement of the system and the ramping capability of the power plant with varying amount of wind over time horizons from 1 hour to 12 hours. Outputs from WSAT and GRT will support decisions of the Grid Controller at EirGrid with regards to dispatch of wind generation through EirGrid´s Wind Dispatch Tool (WDT) which allows two distinct forms of wind dispatch: Curtailment and Constraint.