An Approximately Optimal Algorithm for Scheduling Phasor Data Transmissions in Smart Grid Networks

TL;DR

This paper presents an approximation algorithm for scheduling phasor data transmissions in smart grids, optimizing data flow within the grid's communication infrastructure while considering electrical properties and NP-hard constraints.

Contribution

The paper introduces a novel approximation algorithm for scheduling phasor data that accounts for electrical network properties and NP-hard constraints, improving data transmission efficiency.

Findings

The algorithm achieves near-optimal scheduling performance.

Performance evaluated on IEEE test bus systems.

Provides polynomial-time solutions for a complex NP-hard problem.

Abstract

In this paper, we devise a scheduling algorithm for ordering transmission of synchrophasor data from the substation to the control center in as short a time frame as possible, within the realtime hierarchical communications infrastructure in the electric grid. The problem is cast in the framework of the classic job scheduling with precedence constraints. The optimization setup comprises the number of phasor measurement units (PMUs) to be installed on the grid, a weight associated with each PMU, processing time at the control center for the PMUs, and precedence constraints between the PMUs. The solution to the PMU placement problem yields the optimum number of PMUs to be installed on the grid, while the processing times are picked uniformly at random from a predefined set. The weight associated with each PMU and the precedence constraints are both assumed known. The scheduling problem is provably NP-hard, so we resort to approximation algorithms which provide solutions that are suboptimal yet possessing polynomial time complexity. A lower bound on the optimal schedule is derived using branch and bound techniques, and its performance evaluated using standard IEEE test bus systems. The scheduling policy is power grid-centric, since it takes into account the electrical properties of the network under consideration.