A Dynamical Systems Approach to Modeling and Analysis of Transactive Energy Coordination

TL;DR

This paper introduces a dynamical systems model for transactive energy coordination, analyzing how market factors influence DER behavior, and proposes control strategies to prevent oscillations and improve grid management.

Contribution

It develops an aggregate Markov model of DERs under transactive coordination and integrates it into a model predictive control framework to enhance grid stability and efficiency.

Findings

The model accurately predicts DER aggregate behavior under various market conditions.

Control strategies effectively prevent power oscillations and congestion.

Case study demonstrates economic management of TCLs while avoiding grid issues.

Abstract

Under transactive (market-based) coordination, a population of distributed energy resources (DERs), such as thermostatically controlled loads (TCLs) and storage devices, bid into an energy market. Consequently, a certain level of demand will be cleared based on the operating conditions of the grid. This paper analyzes the influence of various factors, such as price signals, feeder limits, and user-defined bid functions and preferences, on the aggregate energy usage of DERs. We identify cases that can lead to load synchronization, undesirable power oscillations and highly volatile prices. To address these issues, the paper develops an aggregate model of DERs under transactive coordination. A set of Markov transition equations have been developed over discrete ranges (referred to as "bins") of price levels and their associated DER operating states. A detailed investigation of the performance of this aggregate model is presented. With reformulation of the transition equations, the bin model has been incorporated into a model predictive control setting using both mixed integer programming and quadratic programming. A case study shows that a population of TCLs can be managed economically while avoiding congestion in a distribution grid. Simulations also demonstrate that power oscillations arising from synchronization of TCLs can be effectively avoided.