Coordinated Voltage Control for Conservation Voltage Reduction in Power Distribution Systems

摘要

An efficient distribution grid operation can be achieved using network-level optimization modeled as a distribution optimal power flow (D-OPF) problem. The variable power generation profiles of distributed energy resources (DERs) may render the optimal control decisions that are obtained in advance using D-OPF methods to sub-optimal. This paper presents a coordinated centralized and local control approach that simultaneously achieves network-level objective, in this case conservation voltage reduction (CVR), while mitigating the impacts of DER variability on optimal control set-points. The centralized controller solves a D-OPF problem for substation power reduction using a bi-level approach to control the system’s legacy voltage control devices (voltage regulator and capacitor banks) and smart inverters. A penalty successive linear programming (PSLP) approach is used to obtain a computationally tractable DOPF model. Next, an adaptive volt-var droop control for the local control of smart inverters is proposed to minimize the voltage deviations wrt. the centralized control set-points. The proposed coordinated control approach is validated using IEEE 123-node test system, and it is shown to achieve the desired CVR objective even with significant levels of DER variability.