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DOE OSTI · 1524090

Online Static Load Model Estimation in Distribution Systems

Ren, Hongda·Krishnan, Venkat K·Zhang, Yingchen·Schulz, Noel N
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Abstract

This paper focuses on parameter identification for time-varying voltage-dependent polynomial load models in distribution systems—namely, the constant impedance (Z), constant current (I), and constant power (P). The paper assumes the presence of measurements at the distribution nodes from various sources, each at varying temporal resolutions. The least- squares estimation method with bounded variables is used to convert the measurements into ZIP parameter estimations for loads at various locations on the feeder. The results and discussions focus on some of the estimation issues faced in a distribution system caused by varying voltage sensitivities of loads along a feeder, measurement resolution, impact of window size and sampling rate of measurement data. Finally, the paper uses dynamic simulations data (synthetic high-resolution measurements) to further improve the estimation results.

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24 POWER TRANSMISSION AND DISTRIBUTIONLeast-squares estimation, load parameters, voltage measurements, dynamics, distribution systems

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BibTeXRIS

Ren, Hongda, Krishnan, Venkat K, Zhang, Yingchen, Schulz, Noel N. 2019-06-14. Online Static Load Model Estimation in Distribution Systems. https://www.osti.gov/biblio/1524090

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