Operational limitation automation: a simple and modular implementation approach

Following the increase in total electricity generation capacity from renewable energy sources — specifically wind and photovoltaic power plants — and the limited investment in modernizing the national power grid, the power system has now reached a saturation point. Although new generation units could, in principle, be connected to the National Power Grid, the grid’s connection limits have been reached. To enable the integration of new producers or new generating units during the lengthy periods required for reconductoring and grid modernization, the Romanian Energy Regulatory Authority has proposed an operational limitation method that limits the maximum power that can be exported to the grid under N−1 contingency operating conditions. This research article presents a national state-of-the-art review of Operational Limitation Automation (ALO) and a simple, cost-effective implementation approach for this automation using a Phoenix Contact solution.