Multi-conductor feeder design for radial distribution networks

A generalized model for choice of the optimal size of the ACSR type of conductor for each feeder segment is presented as an optimization problem using an efficient method based on branch wise minimization technique. The optimal conductors' sizes are determined by minimizing an objective function (total cost comprising of conductor depreciation cost and annual cost of losses) subject to the constraints on voltage at end load points and maximum current carrying capacity of the feeder segments (branches). Conductors' sizes are first selected according to upper closest maximum current carrying capacities (ampacities) from available conductors' sizes, and then upgraded through economic optimization. Next upgrading conductors in upstream branches of nodes whose voltages violate voltage constraints. The effectiveness of the proposed method (PM) is demonstrated through simulations on several IEEE benchmark Feeders. Due to space limitation only simulation results of two systems are presented. The first is a 69-node system, given by load point locations, their local demand with a graph interconnecting them solved as a module in distribution system planning. The second is an 85-node system for solving optimum reconductoring problem. The results obtained are encouraging.