Capacitor siting using benders decomposition

This paper presents an optimization problem of siting capacitors in a power network to achieve economic benefits. The formulated optimization problem is a nonlinear mixed integer programming problem. In order to find an approximate optimal solution, Benders decomposition is adopted. The optimization problem will be decomposed into a main problem and a subproblem. The subproblem determines dispatch patterns for generators to minimize an objective function if the sites of the capacitors are given. The subproblem is a conventional AC optimal power flow problem. Existing toolboxes such as MATPOWER is used to solve such problems. The subproblem helps to create Benders cuts for the main problem which decides where to put capacitors with a set of cuts introduced accumulatively from the subproblems at each iteration. The main problem is solved by MATLAB CVX toolbox. Numerical results for IEEE 118-bus system are given.