Chance Constraints Optimal Planning Strategy of Energy Storage Systems and Tie-Lines under Wind Power Uncertainties to Improve the Reliability

摘要

The energy storage devices and renewable energy integration have great impacts on modern power system. The optimal siteselection and network expansion under several uncertainties, however, are the challenging tasks in modern interconnectedpower system. This paper proposes a robust optimal planning strategy to find the location and the size of the energy storagesystem (ESS) among the power network buses and transmission lines expansion to accommodate the wind power energyintegration to serve the future demand growth under uncertainties. The proposed methodology provides the optimal locationconcerning the required size of ESS at each bus, along with the optimal selections to reinforce existing lines or recommendingnewones in a single solving stage. The co-optimization problem is formulated as amixed-integer linear programming problem,in which the power balance constraint is developed as an optimal power flow. The stochastic optimization problem is solvedrobustly using the chance-constrained method. Furthermore, the load shedding and wind curtailment are taken into account inthe cost function. The methodology is tested in the IEEE RTS-96 system. The simulation results demonstrate the effectivenessof the proposed strategy to find optimal size and location of ESS. The optimal candidates and transfer capacity for the tie-linesexpansion planning are also determined. The results are found using different confidence levels to assess the optimality whenthe confidence level changes. The primary generation adequacy indices are evaluated to highlight the effectiveness of theproposed methodology. The optimally sized batteries allocated in the optimally selected locations around the system enhancethe system’s performance economically and reliably.