Two-stage approach for the optimal power flow of photovoltaic-penetrated distribution systems

摘要

The paper presents a two-stage model for achieving feasible optimal solution along with numerical validation for the exactness of the available second order cone relaxation in the distribution optimal power flow problem. To this end, the IEEE 13-bus, 34-bus and 123-bus distribution power systems are adapted by balancing the various feeder segments and by populating selected nodes with photovoltaic inverters. The different test feeders are studied under typical daily power profiles. Results generated by Matlab Software for Disciplined Convex Programming (CVX) and the nonlinear solver (fmincon) suggest that second order cone relaxation for the branch flow model is exact only for the case studies of small radial systems but not necessary for large radial systems.