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Title: Stability Assessment of a System Comprising a Single Machine and Inverter with Scalable Ratings

Abstract

From the inception of power systems, synchronous machines have acted as the foundation of large-scale electrical infrastructures and their physical properties have formed the cornerstone of system operations. However, power electronics interfaces are playing a growing role as they are the primary interface for several types of renewable energy sources and storage technologies. As the role of power electronics in systems continues to grow, it is crucial to investigate the properties of bulk power systems in low inertia settings. In this paper, we assess the properties of coupled machine-inverter systems by studying an elementary system comprised of a synchronous generator, three-phase inverter, and a load. Furthermore, the inverter model is formulated such that its power rating can be scaled continuously across power levels while preserving its closed-loop response. Accordingly, the properties of the machine-inverter system can be assessed for varying ratios of machine-to-inverter power ratings and, hence, differing levels of inertia. After linearizing the model and assessing its eigenvalues, we show that system stability is highly dependent on the interaction between the inverter current controller and machine exciter, thus uncovering a key concern with mixed machine-inverter systems and motivating the need for next-generation grid-stabilizing inverter controls.

Authors:
 [1];  [1];  [1];  [2];  [2]
  1. National Renewable Energy Laboratory (NREL), Golden, CO (United States)
  2. University of Minnesota
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Solar Energy Technologies Office (EE-4S)
OSTI Identifier:
1397151
Report Number(s):
NREL/CP-5D00-67974
DOE Contract Number:
AC36-08GO28308
Resource Type:
Conference
Resource Relation:
Conference: Presented at the IEEE North American Power Symposium, 17-19 September 2017, Morgantown, West Virginia
Country of Publication:
United States
Language:
English
Subject:
24 POWER TRANSMISSION AND DISTRIBUTION; sycnhronous generator; inverter; electric grid; stability

Citation Formats

Johnson, Brian B, Lin, Yashen, Gevorgian, Vahan, Purba, Victor, and Dhople, Sairaj. Stability Assessment of a System Comprising a Single Machine and Inverter with Scalable Ratings. United States: N. p., 2017. Web.
Johnson, Brian B, Lin, Yashen, Gevorgian, Vahan, Purba, Victor, & Dhople, Sairaj. Stability Assessment of a System Comprising a Single Machine and Inverter with Scalable Ratings. United States.
Johnson, Brian B, Lin, Yashen, Gevorgian, Vahan, Purba, Victor, and Dhople, Sairaj. 2017. "Stability Assessment of a System Comprising a Single Machine and Inverter with Scalable Ratings". United States. doi:. https://www.osti.gov/servlets/purl/1397151.
@article{osti_1397151,
title = {Stability Assessment of a System Comprising a Single Machine and Inverter with Scalable Ratings},
author = {Johnson, Brian B and Lin, Yashen and Gevorgian, Vahan and Purba, Victor and Dhople, Sairaj},
abstractNote = {From the inception of power systems, synchronous machines have acted as the foundation of large-scale electrical infrastructures and their physical properties have formed the cornerstone of system operations. However, power electronics interfaces are playing a growing role as they are the primary interface for several types of renewable energy sources and storage technologies. As the role of power electronics in systems continues to grow, it is crucial to investigate the properties of bulk power systems in low inertia settings. In this paper, we assess the properties of coupled machine-inverter systems by studying an elementary system comprised of a synchronous generator, three-phase inverter, and a load. Furthermore, the inverter model is formulated such that its power rating can be scaled continuously across power levels while preserving its closed-loop response. Accordingly, the properties of the machine-inverter system can be assessed for varying ratios of machine-to-inverter power ratings and, hence, differing levels of inertia. After linearizing the model and assessing its eigenvalues, we show that system stability is highly dependent on the interaction between the inverter current controller and machine exciter, thus uncovering a key concern with mixed machine-inverter systems and motivating the need for next-generation grid-stabilizing inverter controls.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 9
}

Conference:
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