Voltage and Reactive Power in Active Distribution Networks

Increased intake of Distributed and Renewable Generation (DG) causes transformation of distribution networks into active distribution networks (ADN) clustered into microgrids. In this book, three phase power flow algorithms are developed to provide simulation tools of ADNs and microgrids. Using the developed power flow tools, the issues of voltage and reactive power (Volt/Var) control are assessed in order to shed the light on the potential conflicts that are expected with high DG penetration. The problem of optimal sizing and allocation of Volt/Var resources is reformulated to account for the characteristics of ADNs clustered into microgrids and capable of operating in both grid-connected and islanded modes of operation. Moreover, smart grid offers new digital technologies to be combined with the existing utility grids to substantially improve the overall efficiency and reliability of the network. Advanced network monitoring, two ways communication and intelligent control methods represent the main features of smart grids. Hence, a two ways communication-based distributed control is developed in this book to provide smart Volt/Var control in ADNs under the smart grid paradigm.