Zoning Evaluation for Voltage Control in Smart Distribution Networks

To optimize the voltage profile of distribution systems, in this paper a centralized control is adopted for determining the set-points of the controllers of the distributed energy resources connected to the grid. The voltage regulation is achieved by solving a voltage optimization problem subject to power flow equations and network constraints. To avoid solving a large non-linear programming, an innovative linear method for the steady-state operation of distribution systems is adopted to perform both sensitivity analysis and linear modeling. Sensitivity analysis is used to divide the network in voltage control zones and to identify in each of them the pilot node, so as to reduce the number of nodal voltages to be optimized. Linear modeling of the distribution system is used in place of the power flow equations to solve a quadratic programming problem. Results of a case study give evidence of the effectiveness of the proposed approach.