On-line assessment of secure level of wind on the Irish power system

A Wind penetration Secure level Assessment Tool (WSAT) is currently being developed by EirGrid Pic and Powertech Labs Inc that will help maximising use of its wind power generation while maintaining secure operation of the Irish power system. The tool is based on voltage and transient security analysis of transfers between wind and conventional power generation. In on-line WSAT application WSAT obtains modified power flow snap-shot file from SCADA/EMS and runs real-time voltage and transient stability assessment of mentioned transfers. When one of the security criteria limits is reached, the amount of corresponding wind generation with agreed margin is considered as wind generation limit according to this criterion. At present three such criteria are used for steady-state analysis of base case and N-l contingencies: thermal limits of the equipment, voltage levels of the buses and voltage collapse; and one criterion for dynamic analysis: transient frequency drop below set limit for three-phase faults on the system cleared within assumed clearance times and/or loss of conventional generation. With getting more experience with WSAT we will be adding other criteria, e.g. voltage steps, voltage changes etc. WSAT also automatically estimates wind generation limits for next 24 hours using topology data from most recent snapshot file and generation schedule from Reserve constrained unit commitment program.