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A recursive system identification inertia estimator for traditional and converter-interfaced generators
  • Davide Gotti ,
  • Pablo Ledesma ,
  • Hortensia Amaris
Davide Gotti
Universidad Carlos III de Madrid, Universidad Carlos III de Madrid

Corresponding Author:[email protected]

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Pablo Ledesma
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Hortensia Amaris
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This paper proposes a method to estimate the inertia constant of synchronous generators (SGs) and the virtual inertia provided by converter-interfaced generators (CIGs). It can be applied when the system is under normal operating conditions or after power imbalance events. The algorithm is based on a recursive system identification approach and uses the active power and bus frequency measurements proceeding from phasor measurement units. The measurements are preprocessed to improve the estimation accuracy. Subsequently, a model-independent rotor speed estimator is used to compute rotor speed variations (or internal frequency variations, in the case of CIGs). Afterwards, a recursive least-square equation error formulation is implemented to compute the SG and CIG parameters in the z-domain, which are later converted into their respective counterparts in the s-domain. The method is applied to several generation devices in the IEEE 39-bus and IEEE 118-bus test systems, including traditional SGs and CIGs providing virtual inertia. Numerical results show the accuracy and the low computational burden of the proposed method.
Dec 2023Published in International Journal of Electrical Power & Energy Systems volume 154 on pages 109445. 10.1016/j.ijepes.2023.109445