A Hierarchical Volt-var Optimization with Discrete Variables in Unbalanced Distribution Systems

Conference · Thu Jan 30 04:00:00 EST 2020

DOI:https://doi.org/10.1109/PESGM40551.2019.8973834· OSTI ID:1810303

Nguyen, Quan H. ^[1]; Lao, Keng-Weng ^[2]; Santoso, Surya ^[2]; Chirapongsananurak, Pisitpol ^[3]

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1. BATTELLE (PACIFIC NW LAB)
2. University of Texas at Austin
3. Chulalongkorn University

This paper proposes a framework to determine the optimal active and reactive power dispatch of distributed photovoltaic (PV) generation, switched capacitors, and voltage regulators in multi-phase unbalanced distribution systems. The objectives of the optimal dispatch are minimization of the energy loss, PV real power curtailment, and switching operations of capacitors and voltage regulators, in addition to elimination of voltage violation and reverse power flow. The optimization problem is formulated in rectangular coordinates as a nonlinear, nonconvex problem with discrete variables. A hierarchical twostage framework is proposed to effectively handle those discrete variables and reduce the computational time compared to the unified approach in which all variables are solved simultaneously. The efficacy of the proposed approach and the accuracy of the obtained numerical solution is validated using the unbalanced multi-phase IEEE 34-bus with 15-minute load and PV data.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1810303
• Report Number(s): PNNL-SA-146079
• Country of Publication: United States
• Language: English