Soft Open Points for Optimising Flexibility Exploitation in Power Distribution Networks

Carcangiu, Sara;Celli, Gianni

;Parehar, Mansoor U. M.;Pilo, Fabrizio

2026-01-01

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Abstract

Soft open points (SOPs) are installed in place of normally open tie switches, enabling controlled power exchange between adjacent feeders, typically to improve power quality in distribution networks. The main novelty of the paper is to consider this device a valuable solution for enabling the exploitation of the flexibility provided by distributed energy resources (DERs). A linear-programming operational planning framework is presented to quantify the value of coordinating SOPs with DERs for flexibility-oriented operation of distribution networks. The model optimises renewable generation curtailment and demand response along with SOP terminal active/reactive setpoints. Network adequacy and security are guaranteed through sensitivity-based linearised technical constraints around a forecast operating point, under steady and emergency network configurations. The N - 1 assessment applies a practical restoration policy that tests available network reconfiguration options and selects the one that reduces the load not served. In the post-fault topology, one SOP operates as a closed-tie switch to restore supply while keeping other devices controllable. The methodology is applied to a realistic Italian MV network and evaluated across monthly load and generation profiles. The proposed formulation provides a scalable and interpretable tool for assessing how SOP coordination impacts flexibility, procurement needs and security-constrained operating costs.