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Title: Data-Driven Time-Varying Inertia Estimation of Inverter-Based Resources
This letter proposes a data-driven inertia estimator for inverter-based resources (IBRs) with grid-forming control. It is able to track both constant and time-varying inertia. By utilizing the Thevenin equivalent, the virtual frequency inside IBRs is first estimated with only its terminal voltage and current phasor measurements. The virtual frequency and the measurements are then used together to derive the state-space swing equation model. Then, an enhanced adaptive Unscented Kalman filter (EAUKF) is developed to estimate IBR inertia. Numerical results on the modified IEEE 39-bus power system demonstrate that the proposed inertia estimator remarkably outperforms the existing state-of-art methods both in tracking speed and accuracy.  more » « less
Award ID(s):
2328241 2550498
PAR ID:
10530278
Author(s) / Creator(s):
;
Publisher / Repository:
IEEE
Date Published:
Journal Name:
IEEE Transactions on Power Systems
Volume:
38
Issue:
2
ISSN:
0885-8950
Page Range / eLocation ID:
1795 to 1798
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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