Optimal operation for reliability assessment of a radial distribution systems

This paper presents an efficient algorithm for determining the minimal changes in transformer taps to control voltage levels while at the same time maintaining a practical reliability assessment for radial distribution systems, The problem to be solved is cast into a nonlinear constraint optimization. The constraints are tackled in the minimization algorithm by forming the Lagrangian. Necessary conditions for optimally are derived and solved using the Newton - Raphson method. The algorithm is efficient for large - scale radial distribution systems and can accommodate the effects of fault isolation and load restoration. The proposed algorithm is demonstrated by application to a practical system example.