A multiobjective placement of switching devices in distribution networks incorporating distributed energy resources

With the growth of Distributed Energy Resources (DER) in electrical systems, an increase in the benefits with the reconfiguration of radial networks related to the use of renewable energy is expected. However, in some countries the reconfiguration of radial networks has some limitations like the impossibility of island operation. Also, many of them have contracts with Distributed Generation (DG) operators that force them to buy all the available generation of electricity. After a fault these limitations increase DG unavailability resulting in a waste of resources in the form of payments of available electricity generation not used. In this paper we propose a multiobjective optimal placement of switching devices considering DG unavailability, network reliability and equipment cost, with no island network operation. Two approaches are proposed in this multiobjective problem. In the first approach, besides the minimization of the equipment cost and the reliability indices, it is proposed an extra objective function that considers the minimization of the Distributed Generation Unavailability Index (DGUI). In the second approach two new composite indices comprising DG, interruption duration and interruption frequency are presented. Results obtained from a case study using a real utility distribution network are presented and discussed. (C) 2015 Elsevier B.V. All rights reserved.