A Linear AC-OPF Formulation for Unbalanced Distribution Networks

Giraldo, Juan S.; Vergara Barrios, P.P.; Lopez, Juan Camilo; Nguyen, Phuong H.; Paterakis, Nikolaos G.

doi:10.1109/TIA.2021.3085799

A Linear AC-OPF Formulation for Unbalanced Distribution Networks

Title

A Linear AC-OPF Formulation for Unbalanced Distribution Networks

Author

Giraldo, Juan S. (University of Twente)
Vergara Barrios, P.P. (TU Delft Intelligent Electrical Power Grids)
Lopez, Juan Camilo (University of Campinas)
Nguyen, Phuong H. (Eindhoven University of Technology)
Paterakis, Nikolaos G. (Eindhoven University of Technology)

Date

2021

Abstract

Linear optimal power flow (OPF) formulations are powerful tools applied to a large number of problems in power systems, e.g., economic dispatch, expansion planning, state estimation, congestion management, electricity markets, among others. This article proposes a novel mixed-integer linear programming formulation for the ac-OPF of three-phase unbalanced distribution networks. The model aims to minimize the total energy production cost while guaranteeing the network's voltage and current magnitude operational limits. New approximations of the Euclidean norm, which is present in the calculation of nodal voltage and branch current magnitudes, are introduced by applying a linear transformation of weighted norms and a set of intersecting planes. The accuracy, optimality, feasibility, and scalability of the proposed linearizations are compared with common linear approximations in the literature using two unbalanced distribution test systems. The obtained results show that the proposed formulation is computationally more efficient (almost twice) while being as accurate and more conservative than the benchmarked approaches with maximum errors lower than 0.1%. Thus, its potential application in a variety of distribution systems operation and planning optimization problems is endorsed.

Subject

Ac optimal power flow
Euclidean norm approximation
mixed-integer linear programming
unbalanced distribution networks

To reference this document use:

http://resolver.tudelft.nl/uuid:23877a19-5f8c-4b5b-aef4-1a25dada8385

DOI

https://doi.org/10.1109/TIA.2021.3085799

ISSN

0093-9994

Source

IEEE Transactions on Industry Applications, 57 (5), 4462-4472

Bibliographical note

Accepted author manuscript