With the proliferation of large-scale grid-connected wind farms, subsynchronous oscillations (SSOs) incidents associated with Type-4 wind turbines (WTs) with a permanent magnet synchronous generator (PMSG) occurred frequently. These incidents have caused severe reliability risks to the power grid. Conventionally, P-Q capability charts are utilized to ensure the safety operating region of a synchronous generator. However, a PMSG WT exhibits a complete different and dynamic P-Q capability characteristics due to the difference in energy conversion technique and several other critical factors related to the power converters of the WT. This paper presents a comprehensive dynamic P-Q capability study of a PMSG WT with sufficient and accurate considerations of the WT control and operation in the dq reference frame, its specific power converter constraints, variable grid conditions, etc. Models of a PMSG WT are first developed based on its control principle in the dq reference frame. Then, algorithms for obtaining the P-Q capability charts of the WT are developed with the considerations of complete WT constraints in different aspects. The proposed study is verified via an electromagnetic transient (EMT) model of a grid-connected Type-4 WT.
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Exploring Dynamic P-Q Capability and Abnormal Operations Associated with PMSG Wind Turbines
With the proliferation of large-scale grid-connected wind farms, subsynchronous oscillation (SSO) incidents associated with Type-4 wind turbines (WTs) with a permanent magnet synchronous generator (PMSG) have occurred frequently. These incidents have caused severe reliability risks to the power grid. Conventionally, P-Q capability charts are utilized to ensure the safety operating region of a synchronous generator. However, a PMSG WT exhibits completely different and dynamic P-Q capability characteristics due to the difference in energy conversion technique and several critical factors related to the WT power converters. This paper presents a comprehensive dynamic P-Q capability study of a PMSG WT with sufficient and accurate considerations of the WT control and operation in the dq reference frame, its power converter constraints, and grid dynamics. Models of a PMSG WT are first developed based on its control principle in the dq reference frame. Then, algorithms for obtaining the P-Q capability charts of the WT are developed with the considerations of complete WT constraints in different aspects. The study analyzes the root cause of many abnormal operations of grid-connected PMSG WTs, reported in the literature, from the dynamic P-Q capability perspectives. The proposed study is verified via an electromagnetic transient (EMT) model of a grid-connected Type-4 WT.
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- Award ID(s):
- 2141067
- PAR ID:
- 10500723
- Publisher / Repository:
- MDPI
- Date Published:
- Journal Name:
- Energies
- Volume:
- 16
- Issue:
- 10
- ISSN:
- 1996-1073
- Page Range / eLocation ID:
- 4116
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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