**About the Editors**

**Antonio Cataliotti** (Full Professor) received his M.S. and Ph.D. degrees in Electrical Engineering from University of Palermo, in 1992 and 1998, respectively. He is currently Full Professor in electrical and electronic measurements with the Department of Engineering of the University of Palermo. His current research interests include power quality measurements, power line communications, and smart grids.

**Dario Di Cara** (Ph.D.) received his M.S. and Ph.D. degrees in Electrical Engineering from University of Palermo, in 2005 and 2009, respectively. He is currently Researcher with the Institute of Marine Engineering of the Italian National Research Council, Palermo, Italy. His current research interests include power quality measurements, characterization of current transducers in non-sinusoidal conditions, power line communications, and smart grids.

**Giovanni Artale** (Ph.D.) received his M.S. degree in Electronic Engineering and Ph.D. degree in Electronic and Telecommunications Engineering from the University of Palermo, Palermo, Italy, in 2010 and 2014, respectively. He is currently Research Fellow with the Department of Engineering of the University of Palermo. His current research interests include low-frequency harmonic analysis algorithms, arc fault research methods, power line communications, and smart grids.

#### **Preface to "Medium/Low Voltage Smart Grids"**

In the last decade, medium voltage (MV) and low voltage (LV) distribution networks are experiencing many changes due to the high increase in distributed generation from renewable energy sources, connection of new electric loads (such as electric vehicles), integration of energy storage systems, progressive participation of passive users to demand response strategies and introduction of new players in the energy market (including energy aggregators and virtual power plant, among others), and development of novel strategies for smart metering. In this panorama, distribution system operators need to revise their network managemen<sup>t</sup> strategies, performing constant monitoring of the whole distribution network and interacting with distributed generators, energy storage systems, passive users, and energy aggregators.

This book is a collection of manuscripts proposing original and innovative solutions for accurate distributed monitoring systems and related innovative measurement instruments, distribution grid state forecast algorithms, active distribution networks with distributed generation, frequency and voltage control for network stability and quality of service, and communication systems to acquire distributed measurement data, send commands, and receive alarms. The introduction of these innovative solutions can pave the way for the effective transformation of MV and LV networks into smart grids.

The book aims to provide readers, Ph.D. students as well as research personnel and professional engineers with information not only on theoretical studies of the recent developments but also the practical application of the proposed solutions for smart grid applications both in LV and MV networks. The manuscripts of this book were developed by renowned researchers and specialists from around the world.

> **Antonio Cataliotti, Dario Di Cara, Giovanni Artale** *Editors*

### **Incremental Heuristic Approach for Meter Placement in Radial Distribution Systems**

#### **Giovanni Artale 1, Antonio Cataliotti 1, Valentina Cosentino 1, Dario Di Cara 2,\*, Salvatore Guaiana 1, Enrico Telaretti 1, Nicola Panzavecchia 2 and Giovanni Tinè 2**


Received: 26 September 2019; Accepted: 15 October 2019; Published: 16 October 2019

**Abstract:** The evolution of modern power distribution systems into smart grids requires the development of dedicated state estimation (SE) algorithms for real-time identification of the overall system state variables. This paper proposes a strategy to evaluate the minimum number and best position of power injection meters in radial distribution systems for SE purposes. Measurement points are identified with the aim of reducing uncertainty in branch power flow estimations. An incremental heuristic meter placement (IHMP) approach is proposed to select the locations and total number of power measurements. The meter placement procedure was implemented for a backward/forward load flow algorithm proposed by the authors, which allows the evaluation of medium-voltage power flows starting from low-voltage load measurements. This allows the reduction of the overall costs of measurement equipment and setup. The IHMP method was tested in the real 25-bus medium-voltage (MV) radial distribution network of the Island of Ustica (Mediterranean Sea). The proposed method is useful both for finding the best measurement configuration in a new distribution network and also for implementing an incremental enhancement of an existing measurement configuration, reaching a good tradeo ff between instrumentation costs and measurement uncertainty.

**Keywords:** optimal meter placement; smart grid; load flow analysis; Monte Carlo methods
