# OPTIMIZATION TOOLS ADRESSING FUZZY UNCERTAINTY AT POWER FLOWS

### Eduardo M. Gouveia, Paulo Moisés Costa

#### Abstract

Power flow studies use computational tools for the planning and operation of electrical power systems purposes. The deterministic model is the most commonly used load flow approach. In this model, the input data and the results are crisp values. Therefore, to account for uncertainties, the most common approach used is the definition of scenarios, which are characterized by crisp values. This is an impractical way to solve the problem of the uncertainty in the data. A more practical way to lead with the uncertainties is the use of probabilistic power flows. On such approach, the uncertainties are modelled through the use of probability density functions (pdf). However, that approach may be inappropriate, namely when there is no available historical data in order to construct the pdf. On such cases, the fuzzy power flows (FPF) is an interesting alternative. In this paper, a methodology named Symmetric Fuzzy Power Flow is used. That methodology uses optimization models to solve power flow problems considering the uncertainty treated as fuzzy numbers. A comparison between the proposed methodology and the classic ones is also provided.

#### References

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#### Paper Citation

#### in Harvard Style

M. Gouveia E. and Moisés Costa P. (2012). **OPTIMIZATION TOOLS ADRESSING FUZZY UNCERTAINTY AT POWER FLOWS** . In *Proceedings of the 1st International Conference on Operations Research and Enterprise Systems - Volume 1: ICORES,* ISBN 978-989-8425-97-3, pages 219-222. DOI: 10.5220/0003760502190222

#### in Bibtex Style

@conference{icores12,

author={Eduardo M. Gouveia and Paulo Moisés Costa},

title={OPTIMIZATION TOOLS ADRESSING FUZZY UNCERTAINTY AT POWER FLOWS},

booktitle={Proceedings of the 1st International Conference on Operations Research and Enterprise Systems - Volume 1: ICORES,},

year={2012},

pages={219-222},

publisher={SciTePress},

organization={INSTICC},

doi={10.5220/0003760502190222},

isbn={978-989-8425-97-3},

}

#### in EndNote Style

TY - CONF

JO - Proceedings of the 1st International Conference on Operations Research and Enterprise Systems - Volume 1: ICORES,

TI - OPTIMIZATION TOOLS ADRESSING FUZZY UNCERTAINTY AT POWER FLOWS

SN - 978-989-8425-97-3

AU - M. Gouveia E.

AU - Moisés Costa P.

PY - 2012

SP - 219

EP - 222

DO - 10.5220/0003760502190222