Linear/Quadratic Programming-Based Optimal Power Flow using Linear Power Flow and Absolute Loss Approximations

TL;DR

This paper introduces linear and quadratic programming approximations for the nonlinear AC optimal power flow problem, enabling faster and near-optimal solutions suitable for power system planning and operation.

Contribution

The paper develops novel linear and quadratic approximations of AC optimal power flow using linear power flow and absolute loss functions, improving computational efficiency.

Findings

Errors on voltage magnitudes and angles are reasonable.

Methods achieve near-optimal results in typical scenarios.

Significant reduction in computational complexity.

Abstract

This paper presents novel methods to approximate the nonlinear AC optimal power flow (OPF) into tractable linear/quadratic programming (LP/QP) based OPF problems that can be used for power system planning and operation. We derive a linear power flow approximation and consider a convex reformulation of the power losses in the form of absolute value functions. We show four ways how to incorporate this approximation into LP/QP based OPF problems. In a comprehensive case study the usefulness of our OPF methods is analyzed and compared with an existing OPF relaxation and approximation method. As a result, the errors on voltage magnitudes and angles are reasonable, while obtaining near-optimal results for typical scenarios. We find that our methods reduce significantly the computational complexity compared to the nonlinear AC-OPF making them a good choice for planning purposes.