Distributed Primal-Dual Interior Point Framework for Analyzing Infeasible Combined Transmission and Distribution Grid Networks

TL;DR

This paper introduces a distributed primal-dual interior point method for analyzing infeasible combined transmission and distribution networks, enabling efficient identification of weak spots in large interconnected power systems.

Contribution

It develops a unified solution algorithm using a Gauss-Jacobi-Newton approach for infeasible T&D networks, improving over existing methods like ADMM.

Findings

Successfully models large T&D networks with over 70,000 transmission nodes and 15,000 distribution nodes.

Demonstrates performance improvements over the ADMM method.

Effectively isolates weak nodes in combined power systems.

Abstract

The proliferation of distributed energy resources has heightened the interactions between transmission and distribution (T&D) systems, necessitating novel analyses for the reliable operation and planning of interconnected T&D networks. A critical gap is an analysis approach that identifies and localizes the weak spots in the combined T\&D networks, providing valuable information to system planners and operators. The research goal is to efficiently model and simulate infeasible (i.e. unsolvable in general settings) combined positive sequence transmission and three-phase distribution networks with a unified solution algorithm. We model the combined T&D network with the equivalent circuit formulation. To solve the overall T&D network, we build a Gauss-Jacobi-Newton (GJN) based distributed primal dual interior point optimization algorithm capable of isolating weak nodes. We validate the approach on large combined T&D networks with 70k+ T and 15k+ D nodes and demonstrate performance improvement over the alternating direction method of multipliers (ADMM) method.