Volt-Var Optimization of Distribution Systems for Coordinating Utility Voltage Control with Smart Inverters

摘要

The Volt-Var control of smart inverters has drawn wide attention as one of the solutions to the voltage regulation of distribution systems with high PV penetration. Unlike utility voltage control devices, such as on-load tap changers and switched capacitors, smart inverters can provide fast and continuous voltage regulation. This paper describes a new Volt-Var optimization scheme that coordinates the utility control of switched capacitors and on-load tap changers with Volt-Var droop control of smart PV inverters. A voltage-load sensitivity matrix is used to form a linear relationship between control variables and bus voltages. A successive linear programming technique is applied to transform the original mixed-integer nonconvex programing problem into a sequence of mixed-integer linear programming problems. The proposed Volt-Var optimization model is validated on a 47-bus distribution circuit and the results show that the method is effective in improving voltage regulation as well as reducing the operations of on-load tap changers.