Virtual-Voltage Partition-Based Approach to Optimal Transmission Switching

TL;DR

This paper presents a novel virtual-voltage approximation and graph partitioning algorithm to efficiently solve the complex optimal transmission switching problem with discrete decisions and non-convex constraints, achieving accurate results with manageable computation.

Contribution

It introduces a physically-inspired virtual-voltage approximation and a graph partition-based method to improve solution bounds and computational efficiency for the optimal transmission switching problem.

Findings

High accuracy in solution bounds

Reduced computational complexity

Effective parallel subproblem solving

Abstract

This paper deals with optimal transmission switching (OTS) problems involving discrete binary decisions about network topology and non-convex power flow constraints. We adopt a semidefinite programming formulation for the OPF problem which, however, remains nonconvex due to the presence of discrete variables and bilinear products between the decision variables. To tackle the latter, we introduce a novel physically-inspired, virtual-voltage approximation that leads to provable lower and upper bounds on the solution of the original problem. To deal with the exponential complexity caused by the discrete variables, we introduce a graph partition-based algorithm which breaks the problem into several parallel mixed-integer subproblems of smaller size. Simulations demonstrate the high degree of accuracy and affordable computational requirements of our approach.