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DOE OSTI · 1808035

Iteration-based Linearized Distribution-level Locational Marginal Price for Three-phase Unbalanced Distribution Systems

Cai, Mengmeng·Yang, Rui·Zhang, Yingchen
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Abstract

Distributed energy resources (DERs) are rocking the utilities’ business landscape. It calls for competitive market environments that incentivize DERs to form maximum operating efficiency. Among proposed pricing schemes, distribution-level locational marginal price (DLMP) is effective in signaling the marginal generation cost differences driven by energy losses and network constraints. It can be derived from a distribution-level optimal power flow (OPF) framework, as it essentially presents the sensitivity of optimized generation cost towards incremental loads. However, due to the high resistance-to-inductance ratio and unbalanced characteristics of distribution networks, computational affordable DLMPs are highly challenged. This article provides a linear-approximated DLMP that can be solved efficiently and generalized to account for reactive power flow, three-phase unbalanced loads and meshed network structure. The successive linear programming technique is introduced to enhance the model accuracy. Case studies on an IEEE 123-Bus system validate its accuracy against a nonlinear benchmark and capability in offering proper incentives.

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24 POWER TRANSMISSION AND DISTRIBUTIONdistribution-level LMPlinear OPFsuccessive linear programming

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Cai, Mengmeng, Yang, Rui, Zhang, Yingchen. 2021-07-05. Iteration-based Linearized Distribution-level Locational Marginal Price for Three-phase Unbalanced Distribution Systems. https://doi.org/10.1109/tsg.2021.3094494

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