Discovery and Characterization of Cross-Area and Intra-Area SSOs Sensitive to Delay in Droop Control of Grid-Forming Converters

Lilan Karunaratne; Nilanjan Ray Chaudhuri; Amirthagunaraj Yogarathnam; Meng Yue

doi:10.1109/NAPS66256.2025.11272289

Discovery and Characterization of Cross-Area and Intra-Area SSOs Sensitive to Delay in Droop Control of Grid-Forming Converters

Lilan Karunaratne
, Nilanjan Ray Chaudhuri
, Amirthagunaraj Yogarathnam
, Meng Yue

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

Abstract

Subsynchronous oscillations (SSOs) involving grid-forming converters (GFCs) are in a less familiar territory of power system dynamics. This paper reports a new phenomenon namely cross-area SSOs in grids with 100% droop-controlled GFC-based renewable penetration, which was discovered during our study on evaluating the adequacy of quasistationary phasor calculus (QPC) and space phasor calculus (SPC)-based models in capturing SSOs. We present frequency-domain characterization of such oscillatory modes in addition to intra-area SSOs in grids involving GFCs and study the impact of a delay in power-frequency droop feedback loop in regards to their stability. Electromagnetic transient (EMT) simulations validate our findings.

Original language	English (US)
Title of host publication	2025 57th North American Power Symposium, NAPS 2025
Publisher	Institute of Electrical and Electronics Engineers Inc.
ISBN (Electronic)	9781665477963
DOIs	https://doi.org/10.1109/NAPS66256.2025.11272289
State	Published - 2025
Event	57th North American Power Symposium, NAPS 2025 - Storrs, United States Duration: Oct 26 2025 → Oct 28 2025

Publication series

Name	2025 57th North American Power Symposium, NAPS 2025

Conference

Conference	57th North American Power Symposium, NAPS 2025
Country/Territory	United States
City	Storrs
Period	10/26/25 → 10/28/25

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

SDG 7 Affordable and Clean Energy

All Science Journal Classification (ASJC) codes

Energy Engineering and Power Technology
Renewable Energy, Sustainability and the Environment
Electrical and Electronic Engineering
Safety, Risk, Reliability and Quality
Control and Optimization
Modeling and Simulation

Access to Document

10.1109/NAPS66256.2025.11272289

Cite this

Karunaratne, L., Chaudhuri, N. R., Yogarathnam, A., & Yue, M. (2025). Discovery and Characterization of Cross-Area and Intra-Area SSOs Sensitive to Delay in Droop Control of Grid-Forming Converters. In 2025 57th North American Power Symposium, NAPS 2025 (2025 57th North American Power Symposium, NAPS 2025). Institute of Electrical and Electronics Engineers Inc.. https://doi.org/10.1109/NAPS66256.2025.11272289

Karunaratne, Lilan ; Chaudhuri, Nilanjan Ray ; Yogarathnam, Amirthagunaraj et al. / Discovery and Characterization of Cross-Area and Intra-Area SSOs Sensitive to Delay in Droop Control of Grid-Forming Converters. 2025 57th North American Power Symposium, NAPS 2025. Institute of Electrical and Electronics Engineers Inc., 2025. (2025 57th North American Power Symposium, NAPS 2025).

@inproceedings{68235e13d4594a5dba8f8a14c50865b5,

title = "Discovery and Characterization of Cross-Area and Intra-Area SSOs Sensitive to Delay in Droop Control of Grid-Forming Converters",

abstract = "Subsynchronous oscillations (SSOs) involving grid-forming converters (GFCs) are in a less familiar territory of power system dynamics. This paper reports a new phenomenon namely cross-area SSOs in grids with 100\% droop-controlled GFC-based renewable penetration, which was discovered during our study on evaluating the adequacy of quasistationary phasor calculus (QPC) and space phasor calculus (SPC)-based models in capturing SSOs. We present frequency-domain characterization of such oscillatory modes in addition to intra-area SSOs in grids involving GFCs and study the impact of a delay in power-frequency droop feedback loop in regards to their stability. Electromagnetic transient (EMT) simulations validate our findings.",

author = "Lilan Karunaratne and Chaudhuri, \{Nilanjan Ray\} and Amirthagunaraj Yogarathnam and Meng Yue",

note = "Publisher Copyright: {\textcopyright} 2025 IEEE.; 57th North American Power Symposium, NAPS 2025 ; Conference date: 26-10-2025 Through 28-10-2025",

year = "2025",

doi = "10.1109/NAPS66256.2025.11272289",

language = "English (US)",

series = "2025 57th North American Power Symposium, NAPS 2025",

publisher = "Institute of Electrical and Electronics Engineers Inc.",

booktitle = "2025 57th North American Power Symposium, NAPS 2025",

address = "United States",

}

Karunaratne, L, Chaudhuri, NR, Yogarathnam, A & Yue, M 2025, Discovery and Characterization of Cross-Area and Intra-Area SSOs Sensitive to Delay in Droop Control of Grid-Forming Converters. in 2025 57th North American Power Symposium, NAPS 2025. 2025 57th North American Power Symposium, NAPS 2025, Institute of Electrical and Electronics Engineers Inc., 57th North American Power Symposium, NAPS 2025, Storrs, United States, 10/26/25. https://doi.org/10.1109/NAPS66256.2025.11272289

Discovery and Characterization of Cross-Area and Intra-Area SSOs Sensitive to Delay in Droop Control of Grid-Forming Converters. / Karunaratne, Lilan; Chaudhuri, Nilanjan Ray; Yogarathnam, Amirthagunaraj et al.
2025 57th North American Power Symposium, NAPS 2025. Institute of Electrical and Electronics Engineers Inc., 2025. (2025 57th North American Power Symposium, NAPS 2025).

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

TY - GEN

T1 - Discovery and Characterization of Cross-Area and Intra-Area SSOs Sensitive to Delay in Droop Control of Grid-Forming Converters

AU - Karunaratne, Lilan

AU - Chaudhuri, Nilanjan Ray

AU - Yogarathnam, Amirthagunaraj

AU - Yue, Meng

PY - 2025

Y1 - 2025

N2 - Subsynchronous oscillations (SSOs) involving grid-forming converters (GFCs) are in a less familiar territory of power system dynamics. This paper reports a new phenomenon namely cross-area SSOs in grids with 100% droop-controlled GFC-based renewable penetration, which was discovered during our study on evaluating the adequacy of quasistationary phasor calculus (QPC) and space phasor calculus (SPC)-based models in capturing SSOs. We present frequency-domain characterization of such oscillatory modes in addition to intra-area SSOs in grids involving GFCs and study the impact of a delay in power-frequency droop feedback loop in regards to their stability. Electromagnetic transient (EMT) simulations validate our findings.

AB - Subsynchronous oscillations (SSOs) involving grid-forming converters (GFCs) are in a less familiar territory of power system dynamics. This paper reports a new phenomenon namely cross-area SSOs in grids with 100% droop-controlled GFC-based renewable penetration, which was discovered during our study on evaluating the adequacy of quasistationary phasor calculus (QPC) and space phasor calculus (SPC)-based models in capturing SSOs. We present frequency-domain characterization of such oscillatory modes in addition to intra-area SSOs in grids involving GFCs and study the impact of a delay in power-frequency droop feedback loop in regards to their stability. Electromagnetic transient (EMT) simulations validate our findings.

UR - https://www.scopus.com/pages/publications/105030493251

UR - https://www.scopus.com/pages/publications/105030493251#tab=citedBy

U2 - 10.1109/NAPS66256.2025.11272289

DO - 10.1109/NAPS66256.2025.11272289

M3 - Conference contribution

AN - SCOPUS:105030493251

T3 - 2025 57th North American Power Symposium, NAPS 2025

BT - 2025 57th North American Power Symposium, NAPS 2025

PB - Institute of Electrical and Electronics Engineers Inc.

T2 - 57th North American Power Symposium, NAPS 2025

Y2 - 26 October 2025 through 28 October 2025

ER -

Karunaratne L, Chaudhuri NR, Yogarathnam A, Yue M. Discovery and Characterization of Cross-Area and Intra-Area SSOs Sensitive to Delay in Droop Control of Grid-Forming Converters. In 2025 57th North American Power Symposium, NAPS 2025. Institute of Electrical and Electronics Engineers Inc. 2025. (2025 57th North American Power Symposium, NAPS 2025). doi: 10.1109/NAPS66256.2025.11272289

Discovery and Characterization of Cross-Area and Intra-Area SSOs Sensitive to Delay in Droop Control of Grid-Forming Converters

Abstract

Publication series

Conference

UN SDGs

All Science Journal Classification (ASJC) codes

Access to Document

Other files and links

Fingerprint

Cite this