Impact Assessment of Synthetic Inertia and Demand Response on Unit Commitment in Electricity Markets

The global concern for climate change has generated heightened interest in Renewable Energy Sources (RES) as alternatives to fossil fuels. As conventional generators are replaced with RES, power system inertia is reducing since RES are connected to the grid through power electronic interfaces that do not directly contribute to inertia. High penetration of RES can lead to critical frequency stability challenges. This paper analyzes the impact of synthetic inertia from energy storage units equipped with inertial frequency response capability and demand response on the dispatch of generators in a day-ahead market. A mathematical unit commitment formulation considering synthetic inertia from battery storage units and demand response is presented. The model is tested with real data from a 24-bus system. The results illustrate the benefits of simultaneously incorporating synthetic inertia and demand response in the unit commitment model.