Risk-based stochastic scheduling of centralised and distributed energy storage systems

The authors propose a continuous-time two-stage stochastic optimisation model for the integration of centralised and distributed energy storage (ES) systems into power systems with high levels of volatile renewable generation. In the proposed model, centralised and distributed ES systems, respectively, controlled by the independent system operator and distribution system operator, can offer energy and flexibility to the operation of the power system in order to help accommodate the uncertainties of renewable generation and load. The proposed model considers the power network constraints and minimises the day-ahead and real-time operation costs of the system in the first and second stages. The proposed model utilises energy and ramping flexibility trajectories of ES systems to enhance the cost-effective operation of the power system, countering the financial risks imposed by the integration of uncertain load and renewable generation. Simulations are conducted on the IEEE 24-bus reliability test system with multiple risk-aversion levels for the power system operator, and the results demonstrate the efficiency of the proposed model in utilising the ES systems to provide energy and ramping flexibility and reducing the financial risks measured by the conditional value at risk.