Conference Paper

Optimal power flow problem with the integrated renewable energy sources: A survey

Authors:
  • COMSATS University Islamabad, Islamabad capmus
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Abstract

In a transmission network, optimal power flow (OPF) is considered as one of the most widely studied non-linear, non-convex and highly constrained problem. While solving the conventional OPF problem, power generation system mainly consists of fossil fuel thermal generators; however, with the increased energy demand, renewable energy sources like wind turbines, solar photovoltaic panels and hydro plants are also introduced. OPF problem is solved using traditional and heuristic approaches to attain the stated objectives that mainly include fuel cost reduction, power loss minimization and emission reduction. These objectives are either optimized individually or in combination where two or more objectives are optimized simultaneously to achieve multi-objective optimization. Further, this study gives an overview of how these economical, environmental and technical objectives are achieved.

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A new optimal reactive power flow (ORPF) model in rectangular form is proposed in this paper. In this model, the load tap changing (LTC) transformer branch is represented by an ideal transformer and its series impedance with a dummy node located between them. The voltages of the two sides of the ideal transformer are then used to replace the turn ratio of the LTC so that the ORPF model becomes quadratic. The Hessian matrices in this model are constants and need to be calculated only once in the entire optimal process, which speed up the calculation greatly. The solution of the ORPF problem by the predictor corrector primal dual interior point method is described in this paper. Two separate prototypes for the new and the conventional methods are developed in MATLAB in order to compare the performances. The results obtained from the implemented seven test systems ranging from 14 to 1338 buses indicate that the proposed method achieves a superior performance than the conventional rectangular coordinate-based ORPF.
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This paper presents a reactive power optimization model that is based on successive quadratic programming (SQP) methods. Mathematical formulation and unified algorithm suppose different objective functions (OF) of reactive power optimization, depending on type and purposes of current reactive power control or planning problem. A bicriterion reactive power optimization model, that represents compromise between economical and security objective functions, is proposed. An efficient algorithm for approximation of initial problem by quadratic programming problem is described. The quadratic programming problem (QP) is solved on the basis of the Newton type quadratic programming method. A modified successive quadratic programming method was developed, that provides reliable convergence of the SQP method
Advances in distribution system analysis with distributed resources: Survey with a case study
  • K Joshi
  • N Pindoriya
Joshi, K. and Pindoriya, N., 2017. Advances in distribution system analysis with distributed resources: Survey with a case study. Sustainable Energy, Grids and Networks, doi, 10.1016/j.segan.2017.12.004, pp.1-15.
An efficient scenario based optimal generation scheduling of hydro-thermal system incorporating wind power
  • A Panda
Panda, A., An efficient scenario based optimal generation scheduling of hydro-thermal system incorporating wind power. International Journal of Recent Trends in Engineering and Research, 4(4), pp.1-7.