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DOE OSTI · 2480252

Generalized Analytical Estimation of Sensitivity Matrices in Unbalanced Distribution Networks

Maharjan, Salish·Cheng, Rui·Wang, Zhaoyu
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Abstract

Fast and accurate estimation of sensitivity matrices is significant for the enhancement of distribution system modeling and automation. Analytical estimations have mainly focused on voltage magnitude sensitivity to active/reactive power injections for unbalanced networks with Wye-connected loads and neglecting DERs' smart inverter functionality. Hence, this paper enhances the scope of analytical estimation of sensitivity matrices for unbalanced networks with 1- Φ, 2- Φ, and 3- Φ Delta/Wye-connected loads, DERs with smart inverter functionality, and substation/line step-voltage regulators (SVR). A composite bus model comprising of DER, Delta- and Wye-connected load is proposed to represent a generic distribution bus, which can be simplified to load, PV, or voltage-controlled bus as required. Furthermore, the proposed matrix-based analytical method consolidates voltage magnitude and angle sensitivity to active/reactive power injection and tap-position of all SVRs into a single algorithm. Extensive case studies on IEEE and EPRI networks show the accuracy and wide scope of the proposed algorithm compared to the existing benchmark method.

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24 POWER TRANSMISSION AND DISTRIBUTIONDistributed energy resourceslinear modelrenewablesstep regulatorsunbalanced distribution networksvoltage sensitivity

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Maharjan, Salish, Cheng, Rui, Wang, Zhaoyu. 2024-02-26. Generalized Analytical Estimation of Sensitivity Matrices in Unbalanced Distribution Networks. https://doi.org/10.1109/tpwrs.2024.3369615

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