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In this paper, we demonstrate methods to extract dq admittance for a solar photovoltaic (PV) farm from its black-box model used for electromagnetic transient (EMT) simulation. Each dq admittance corresponds to a certain operating condition. Based on the dq admittance, analysis is carried out to evaluate how grid strength and solar irradiance may influence stability. Two types of stability analysis methods (open-loop system based and closed-loop system based) are examined and both can deal with dq admittance's frequency-domain measurements directly and produce graphics for stability analysis. The findings based on dq admittance-based analysis are shown to corroborate EMT simulation results.
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DQ Admittance Model Extraction for IBRs via Gaussian Pulse Excitation
While dq admittance models have shown to be very useful for stability analysis, extracting admittance models of inverter-based resources (IBRs) from the electromagnetic transient (EMT) simulation environment using frequency scans takes time. In this letter, a new perturbation method based on Gaussian pulses in combination with the system identification algorithms shows great promise for parametric dq admittance model extraction. We present the dq admittance model extracting method for a type-4 wind turbine. Challenges in implementing Gaussian pulse excitation are also pointed out. The extracted dq admittance model via the new method shows to have a high matching degree with the measurements obtained from frequency scans.
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- Award ID(s):
- 1807974
- PAR ID:
- 10475619
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Transactions on Power Systems
- Volume:
- 38
- Issue:
- 3
- ISSN:
- 0885-8950
- Page Range / eLocation ID:
- 2966 to 2969
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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