Abstract :
In medium voltage (MV) power distribution network planning, especially in rural network planning, we often consider the costs of constructing a backup supply line and the resulting cost reduction for energy not supplied. A fast and simple method for this purpose is now presented. Accurate and approximate expressions for calculating the energy not supplied by a MV feeder with respect to backup supply availability are derived. The optimal number and locations of switching devices on the feeder are determined by use of approximate expressions. The minimum overall costs that consists in the energy not supplied costs and the switching equipment costs, are also calculated. Comparison of the difference in optimal total costs between the situations with and without a backup supply to the connecting line costs in the concerned period serves as a decision-making criterion. The application of the method is shown in the case of 10 kV MV feeder.
