The EirGrid East-West Interconnector Project (EWIP) has been built in order to facilitate the cross-border transportation of power between Britain and Ireland.
The integration of an HVDC system with the AC network required system studies to evaluate its contribution to network operation enhancement. The expert team from Power Consulting has been in charge of these studies.
Addressing the issue
System stability and damping studies have been performed using PSSE for the Irish grid. The results showed stable operation without the need of a damping controller. Additionally, the HVDC operation during emergency conditions such as disconnection of important lines and/or generators has been evaluated for the Irish grid.
Some studies were performed in PSCAD/EMTDC, using very detailed models for the HVDC system. For these studies, reduced network models were required. The AC network reductions for the Irish grid have been performed in PSSE and further implemented in PSCAD/EMTDC.
Sub-synchronous interaction between the HVDC and the nearby generators is a well known effect and therefore the interaction levels have been calculated for both the Irish and British grid by means of PSSE. Further, studies were performed in PSCAD /EMTDC with very detailed HVDC and generator models for some of the generators units on the Irish side. The HVDC has been tuned at these studies in order to avoid interaction problems.
By connecting to the British grid, Ireland will gain access to the European transmission network and respective markets.
The interconnector will enable Ireland to import and export power to and from Britain, thereby creating a more competitive market and reducing customer prices. It will also help Ireland to meet its target of one-third electric power by renewable resources by 2020.
|Power rating:||500 MW|
|No of circuits:||1|
|AC Voltage:||400 kV|
|DC Voltage:||±200 kV|
|Length of DC underground cable:||2 x 75 km|
|Length of DC submarine cable:||2 x 186 km|
|Main reason for choosing HVDC Light®:||Length of land and sea cables, controllability, black start and active reactive power support|