Electric Power Systems Research 105 (2013) 1–8 Contents lists available at SciVerse ScienceDirect Electric Power Systems Research jou rn al hom e page: www.elsevier.com/locate/epsr A methodology for real time analysis of parallelism of distribution networks L.L. Pfitscher a,b , D.P. Bernardon a,∗ , L.N. Canha a , V.F. Montagner a , A.R. Abaide a , J.J.A. Saldanha b a UFSM – Federal University of Santa Maria, RS, Brazil b UNIPAMPA – Federal University of Pampa, RS, Brazil a r t i c l e i n f o Article history: Received 9 May 2013 Received in revised form 5 July 2013 Accepted 8 July 2013 Keywords: Automatic reconfiguration Parallelism Smart Grid Supervisory system Transient analysis a b s t r a c t The parallelism of distribution networks can be used to transfer loads between feeders without the need of disconnection of consumers during the switching. In the context of the Smart Grid, the parallelism of feeders can be used in automatic reconfiguration of networks for the improvement of power quality and voltage levels, and reduction of energy losses. However, the switching for parallelism must be pre- ceded by studies to verify its technical and operational feasibility. This paper presents a methodology to analyze aspects of loading, protection, and voltage levels related to parallelism of distribution networks, in transient and steady-state operation. The validation of the developed methodology was carried out by comparison with simulation results from the ATP program. The study aims to be suitable for real time application in reconfiguration of distribution networks, allowing, for instance, the integration with remote controlled switches, so that the network reconfiguration can be done automatically. The results here presented are based on a real model of a distribution network of a power utility. The developed methodology has as main result a reliable indication of the technical feasibility of connecting feeders in parallel. © 2013 Elsevier B.V. All rights reserved. 1. Introduction The ability of self-reconfiguration in case of changes of service conditions is an important feature for a Smart Grid [1]. The reconfiguration of distribution networks generally has as primary objectives the reduction of losses and the improvement of power quality indicators. In the context of Smart Grid, the reconfiguration should be automatic and in real time, by using information and functionality of electronic equipment remotely accessed, such as switches and power meters. However, the reconfiguration must be preceded by analyses in order to ensure: (i) the improvement of network performance and (ii) the technical feasibility of the required switching. The first aspect is widely discussed in scientific literature [2], with several studies on mathematical, heuristics and artificial intelligence techniques to find the best topology of a distribution network, considering the combinatorial complexity of the network switch- ing elements. The works [3–6] addresses optimization methods for real time reconfiguration with the use of remotely accessed ∗ Corresponding author. Tel.: +55 55 32208792; fax: +55 55 32208030. E-mail addresses: dpbernardon@ufsm.br, dpbernardon@gmail.com (D.P. Bernardon). equipment. The second aspect has gained more attention recently, and addresses issues such as real time studies of load feeders, electromagnetic transients and protection settings. The parallelism allows performing the reconfiguration of networks without interruption of consumers. Due to the switch- ing used for the parallelism, there may be transients harmful to the operation of the network, producing, for instance, overcurrent and swells [7]. Studies of parallelism of feeders are needed as part of the analysis of the technical feasibility of the reconfiguration. Moreover, in steady-state, the loading of the feeders and the levels of voltage and current must not exceed safety limits [8]. The early indication of the viability of the operation of parallelism avoids undue performance of protective devices. Generally, the studies of parallelism are performed based on off line analysis with very simplified models, and the development of more efficient method is appealing. Many works focus on the development of new methodologies of simulation of electromagnetic transients in power systems, consid- ering the high demand for data processing in real networks [9–11]. Some works address the network behavior during parallelism, but they do not present conditions to determine if the analysis results can be effectively applied in a real time reconfiguration. Berman and Markushevich [12] present a sensitivity analysis of phase angle and voltage differences between feeders during parallelism and their 0378-7796/$ – see front matter © 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.epsr.2013.07.003