Very low-frequency oscillations have been occurring on power grids with a high concentration of hydro generation and islanded grids with a lack of AC interconnection. These oscillations can persist in an ambient form or be triggered by a transient event before growing to the extent that threatens system stability. When a severe event occurs, it is important to identify the cause and have practical control actions to restore power system stability. Firstly, this paper demonstrates that synchronising a generator with a positive damping torque component can restore positively damped conditions. Simulations on a modified 2-Area system are evaluated with DIgSILENT PowerFactory. A transport delay is added to speed feedback of a GAST model governor to simulate a spontaneous negatively damped very-low-frequency oscillation with the appearance of being self-excited after a generation load imbalance. Secondly, a 300 mHz 0.08 Hz very-low-frequency oscillation on the Irish electrical grid is analysed using the governor based dissipation energy flow method. Dissipation energy flow is used to illustrate how the synchronisation of 2 generators successfully returned Ireland's power system to positively damped conditions.
|Title of host publication
|2021 32nd Irish Signals and Systems Conference (ISSC 2021): Proceedings
|Institute of Electrical and Electronics Engineers Inc.
|Published - 01 Jul 2021
|32nd Irish Signals and Systems Conference, ISSC 2021 - Athlone, Ireland
Duration: 10 Jun 2021 → 11 Jun 2021
|Irish Signals and Systems Conference: Proceedings
|32nd Irish Signals and Systems Conference, ISSC 2021
|10/06/2021 → 11/06/2021
Bibliographical noteFunding Information:
ACKNOWLEDGEMENTS The authors would like to thank SONI/EirGrid for providing PMU data and generator metadata. The authors would also like to thank DIgSILENT PowerFactory for granting a thesis license to continue research off-campus during COVID-19. The authors would also like to acknowledge the financial support from SPIRE 2 (Storage Platform for the Integration of Renewable Energy) project. The SPIRE 2 project is supported by the European Union’s INTERREG VA Programme (Grant No. INT-VA/049), managed by the Special EU Programmes Body (SEUPB). The views and
© 2021 IEEE.
- Control Decisions
- power system stability
- Very Low-Frequency Oscillations
- wide-area monitoring and control
ASJC Scopus subject areas
- Signal Processing