Modelo multiobjectivo para apoio à localização de condensadores em redes radiais de distribuição

 

Dulce F. Pires *

A. Gomes Martins †

C. Henggeler Antunes †

 

* Escola Superior de Tecnologia de Setúbal - Instituto Politécnico de Setúbal. Portugal

dcosta@est.ips.pt

† Departamento de Engenharia Electrotécnica e Computadores

Faculdade de Ciências e Tecnologia - Universidade de Coimbra. Portugal

† INESC Coimbra. Portugal

{amartins,ch}@deec.uc.pt

Abstract

The installation of shunt capacitors in electrical distribution networks can effectively reduce energy and peak power losses, while improving quality of service particularly promoting a better voltage profile. Economic and operational benefits depend mainly on the number, location and sizes of the capacitors installed.

In this problem, multiple and conflicting evaluation aspects are generally at stake, such as minimizing capacitor installation cost and reducing system losses. Multiple objective models explicitly address these distinct concerns, and they entail analyzing trade-offs between the different objectives to select a satisfactory compromise solution from the set of potentially non-dominated solutions which can be accepted as the output of the decision process.

In this paper, a tabu search based approach is presented, which provides decision support in the problem of capacitor location in radial distribution networks. The model explicitly considers two conflicting and incommensurate objective functions, related to cost and operation aspects of evaluation.

 

Resumo

A instalação de condensadores em redes eléctricas de distribuição reduz efectivamente as perdas de energia e a potência de pico, para além de contribuir para uma melhor qualidade de serviço, nomeadamente na melhoria do perfil de tensões apresentado pela rede. Os benefícios económicos e operacionais obtidos com a colocação de condensadores estão intimamente ligados ao número, localização e dimensão dos dispositivos instalados.

Neste problema existem vários aspectos de avaliação de natureza conflituosa, tais como a redução de perdas e a minimização do custo de instalação das baterias de condensadores. Enveredou-se, por isso, por uma abordagem multiobjectivo, com o desenvolvimento de um modelo que contempla explicitamente os diferentes aspectos de avaliação e permite a selecção de uma solução de compromisso satisfatória, a partir do conjunto de soluções potencialmente não dominadas resultante do processo de pesquisa.

Nesta abordagem, baseada em pesquisa tabu, propõe-se um modelo multiobjectivo de apoio à decisão para o problema da colocação de condensadores em redes de distribuição. O modelo considera explicitamente duas funções objectivo, relacionadas com os aspectos de avaliação referentes ao custo e à redução de perdas.

Keywords: multiobjective models, tabu search, distribution electrical networks.

Title: A multiobjective model for the location of capacitors in radial distribution networks.

 

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