Exact Penalty Function based Constraint Relaxation Method for Optimal Power Flow Considering Wind Generation Uncertainty


This letter presents a constraint relaxation optimal power flow (OPF) model to tackle the issues when traditional OPF is infeasible under large variations such as wind generation output. In this model, the original hard constraints are relaxed into soft constraints and the objective function is adjusted for the cost of constraint violations. To guarantee the equivalence to the original OPF model when there are feasible solutions, an exact penalty function method is introduced to justify the selection of penalty factor of constraint violations. By solving an optimization problem, the lower bound of the proper penalty factor is obtained. The results of a 6-bus test system show that the proposed method achieves the same solution when the original OPF has feasible region, and an optimal solution can be obtained with minimum constraint violation when original OPF has no feasible region. Lastly, three large IEEE systems are tested to verify the effectiveness of proposed method.


Electrical and Computer Engineering

Keywords and Phrases

Acoustic Generators; Electric Load Flow; Optimization; Wind Power; Bi-Level Programming; Constraint Relaxation; Exact Penalty Functions; Karush-Kuhn-Tucker Condition; Optimal Power Flows; Functions; Exact Penalty Function; Karush-Kuhn-Tucker (KKT) Conditions; Optimal Power Flow (OPF)

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Article - Journal

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© 2015 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 May 2015