Real-Time Volt/Var Control in Active Distribution Networks With Data-Driven Partition Method

Abstract

The penetration of photovoltaics (PVs) and electric vehicles (EVs) is increasing in active distribution networks (ADN), which may lead to severe voltage violation problems. This paper proposes a two-stage real-time Volt/Var control method to mitigate fast voltage violations. In the first stage, hourly on-load tap changer (OLTC) and capacitor banks (CBs) are scheduled based on the optimal power flow method. The optimization problem is formulated as a mixed-integer second-order cone programming (MISOCP) which can be effectively solved. In the second stage, a data-driven network partition method is proposed to select critical bus and assess the voltage violation risk of each control area, followed by the intra-day dispatch of EVs. Based on the partition results, reactive power of PVs and EVs is controlled in real-time to mitigate voltage violations. Considering the suddenly active power drop of PVs, a rule-based control strategy coordinating PVs and CBs is proposed to improve the reactive power reserve in ADN. The proposed approach is tested on the IEEE 33-bus and 123-bus distribution networks and simulation results verify the effectiveness both in network partition and real-time voltage control.