Assessing reliability indices in switched distribution networks: A leap in computational efficiency for optimal network topology

Evaluating reliability indices is crucial for addressing operational and planning challenges within distribution networks, ensuring supply continuity, and meeting demand. Developing accurate yet simplified reliability assessment models by reducing the number of variables and constraints significantly enhances the efficiency and precision of solving various relevant problems in modern distribution networks. This paper introduces a novel formulation that utilizes a linear algebraic model to evaluate reliability indices. The open and closed states of the lines are incorporated as control variables, allowing for the determination of an optimal network topology during the reliability index calculation. This approach eliminates the need for predefined sets in selecting the optimal network topology and significantly reduces the number of variables and constraints associated with the optimization problem. Four network scenarios are analyzed: fully switched radial networks and radially operated meshed networks; and partially switched radial networks and radially operated meshed networks. These scenarios reflect practical configurations of real-life distribution systems. The proposed method achieves reductions of up to 50% in variables and 90% in constraints. This substantial decrease in the number of variables and constraints reduces the problem’s computational time, making the method particularly suitable for real-time challenges. In addition to assessing the reliability indices of the entire network, the indices are also computed for each bus. Finally, the performance is evaluated on networks of 37, 85, 137, 417, and 1080 nodes, demonstrating the method’s efficiency and accuracy.