Invited Session Tue.3.MA 549

Tuesday, 15:15 - 16:45 h, Room: MA 549

Cluster 18: Optimization in energy systems [...]

Optimization for power grids


Chair: Arvind Raghunathan and Victor M. Zavala



Tuesday, 15:15 - 15:40 h, Room: MA 549, Talk 1

Arvind Raghunathan
Global optimization of power flow problems

Coauthor: Daniel Nikovski


We consider the solution of optimal power flow (OPF) problems with discrete variables. The discrete variables model changes in transformer positions. The problems falls into the category of non-convex mixed integer nonlinear programs (MINLP). We propose efficient solutions techniques for solving the OPF to global optimality. The performance of the method will be illustrated on several problems from the literature.



Tuesday, 15:45 - 16:10 h, Room: MA 549, Talk 2

Sean Harnett
Robust DCOPF

Coauthors: Daniel Bienstock, Michael Chertkov


We present a formulation for affine control of generator output to compensate for uncertain output of renewable sources. The robustness of the formulation is achieved through SOCP constraints; we present a scalable formulation and numerical experiments.



Tuesday, 16:15 - 16:40 h, Room: MA 549, Talk 3

Naiyuan Chiang
Solving SCOPF problems by a new structure exploiting interior point method

Coauthor: Andreas Grothey


The aim of this paper is to demonstrate a new approach to solve the linearized (n-1) security constrained optimal power flow (SCOPF) problem by OOPS, which is a modern structure-exploiting primal-dual interior-point (IPM) implementation.

Firstly, we present a reformulation of the SCOPF model, in which most matrices that need to be factorized are constant. Consequently, most factorizations and a large number of backsolve operations only need to be performed once throughout the IPM iterations.
Moreover, we suggest to use a preconditioned iterative method to solve the corresponding linear system when we assemble the Schur complement matrix. We suggest several schemes to pick a good and robust preconditioner based on combining different "active'' contingency scenarios. We give results on several SCOPF test problems. The largest example contains 500 buses. We compare the results from the original IPM implementation in OOPS and our new approaches.


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