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Title: Optimal Load-Side Control for Frequency Regulation in Smart Grids

Abstract

Frequency control rebalances supply and demand while maintaining the network state within operational margins. It is implemented using fast ramping reserves that are expensive and wasteful, and which are expected to become increasingly necessary with the current acceleration of renewable penetration. The most promising solution to this problem is the use of demand response, i.e., load participation in frequency control. Yet it is still unclear how to efficiently integrate load participation without introducing instabilities and violating operational constraints. In this paper, we present a comprehensive load-side frequency control mechanism that can maintain the grid within operational constraints. In particular, our controllers can rebalance supply and demand after disturbances, restore the frequency to its nominal value, and preserve interarea power flows. Furthermore, our controllers are distributed (unlike the currently implemented frequency control), can allocate load updates optimally, and can maintain line flows within thermal limits. We prove that such a distributed load-side control is globally asymptotically stable and robust to unknown load parameters. We illustrate its effectiveness through simulations.

Authors:
ORCiD logo [1];  [2];  [3]
  1. National Renewable Energy Laboratory (NREL), Golden, CO (United States)
  2. Johns Hopkins University
  3. California Institute of Technology
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
U.S. Department of Energy, Advanced Research Projects Agency-Energy (ARPA-E)
OSTI Identifier:
1418124
Report Number(s):
NREL/JA-5D00-70834
DOE Contract Number:
AC36-08GO28308
Resource Type:
Journal Article
Resource Relation:
Journal Name: IEEE Transactions on Automatic Control; Journal Volume: 62; Journal Issue: 12
Country of Publication:
United States
Language:
English
Subject:
24 POWER TRANSMISSION AND DISTRIBUTION; power system control; power system dynamics; optimization; demand-side management

Citation Formats

Zhao, Changhong, Mallada, Enrique, and Low, Steven. Optimal Load-Side Control for Frequency Regulation in Smart Grids. United States: N. p., 2017. Web. doi:10.1109/TAC.2017.2713529.
Zhao, Changhong, Mallada, Enrique, & Low, Steven. Optimal Load-Side Control for Frequency Regulation in Smart Grids. United States. doi:10.1109/TAC.2017.2713529.
Zhao, Changhong, Mallada, Enrique, and Low, Steven. 2017. "Optimal Load-Side Control for Frequency Regulation in Smart Grids". United States. doi:10.1109/TAC.2017.2713529.
@article{osti_1418124,
title = {Optimal Load-Side Control for Frequency Regulation in Smart Grids},
author = {Zhao, Changhong and Mallada, Enrique and Low, Steven},
abstractNote = {Frequency control rebalances supply and demand while maintaining the network state within operational margins. It is implemented using fast ramping reserves that are expensive and wasteful, and which are expected to become increasingly necessary with the current acceleration of renewable penetration. The most promising solution to this problem is the use of demand response, i.e., load participation in frequency control. Yet it is still unclear how to efficiently integrate load participation without introducing instabilities and violating operational constraints. In this paper, we present a comprehensive load-side frequency control mechanism that can maintain the grid within operational constraints. In particular, our controllers can rebalance supply and demand after disturbances, restore the frequency to its nominal value, and preserve interarea power flows. Furthermore, our controllers are distributed (unlike the currently implemented frequency control), can allocate load updates optimally, and can maintain line flows within thermal limits. We prove that such a distributed load-side control is globally asymptotically stable and robust to unknown load parameters. We illustrate its effectiveness through simulations.},
doi = {10.1109/TAC.2017.2713529},
journal = {IEEE Transactions on Automatic Control},
number = 12,
volume = 62,
place = {United States},
year = 2017,
month = 6
}
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