From Smart Grids to Smart Cities

New Challenges in Optimizing Energy Grids

Massimo La Scala, Sergio Bruno, Carlo Alberto Nucci, S. Lamonaca, Ugo Stecchi, Massimo La Scala, Sergio Bruno, Carlo Alberto Nucci, S. Lamonaca, Ugo Stecchi

• Publisher: Wiley-ISTE
• Year: 2017
• Print ISBN:
  9781848217492
• eBook ISBN:
  9781119372257
• Edition: 1
• Topic: Physical Sciences
• Subtopic: Energy

This book addresses different algorithms and applications based on the theory of multiobjective goal attainment optimization. In detail the authors show as the optimal asset of the energy hubs network which (i) meets the loads, (ii) minimizes the energy costs and (iii) assures a robust and reliable operation of the multicarrier energy network can be formalized by a nonlinear constrained multiobjective optimization problem. Since these design objectives conflict with each other, the solution of such the optimal energy flow problem hasn't got a unique solution and a suitable trade off between the objectives should be identified. A further contribution of the book consists in presenting real-world applications and results of the proposed methodologies  developed by the authors in  three research projects recently completed and characterized by actual implementation under an overall budget of about 23 million €.

1
Unbalanced Three-Phase Optimal Power Flow for the Optimization of MV and LV Distribution Grids

Smart distribution grids are developed around the concept of advanced distribution management systems (ADSM), whose features are summarized in this Chapter. Optimal power flow (OPF) techniques are a basic function of ADSM and can be applied effectively for controlling distribution grids at both MV and LV voltage levels. Specialized formulations of OPF need to be developed for defining control actions, such as move tap-ratio in on-load tap changers, switch capacitors or disconnectors, change reference signals or price signals to be sent to prosumers or active end-users. A methodology for controlling active and reactive resources in distribution systems, based on the solution of a three-phase unbalanced OPF, has been proposed and tested in this chapter. Particular attention is devoted to low voltage grids due to their importance. These grids are experiencing dramatic changes in power operations and show the potential to take full advantage of throughout metering and control. Test results showed the feasibility of the approach.

1.1. Advanced distribution management system for smart distribution grids

Smart cities take form around advanced physical infrastructures which, thanks to the pervasive presence of sensors, monitoring, communication systems, and the implementation of optimization and control functions, acquire smartness and improve their overall flexibility, security, reliability and efficiency.

The transformation required for achieving smartness in infrastructures of smart cities appears straightforward when electric power systems are considered. Several “smart” functions oriented to the monitoring and control of transmission systems, such as state estimation, topology processor, contingency analysis or dynamic security assessment (DSA), have been customarily in use since the diffusion of control centers and SCADA/EMS in the 1980s. Therefore, a substantial improvement in the smartness of electrical power systems at urban level (basically primary and secondary distribution operating, respectively, at medium voltage MV and low voltage LV level) can be achieved if these same procedures and practices in use for transmission systems were scaled down to distribution.

This basic idea was the principal objective of the earliest formulations of smart distribution networks, usually built around an extensive set of monitoring and control functions embedded centrally in the distribution management system (DMS), or in what it has also been defined as advanced DMS (ADMS). A smart grid, in fact, can be represented with a four-layer structure: the field constituted by physical components (buses, lines, transformers, loads, capacitors, etc.), the set of all measuring and actuating equipment, the ICT layer comprising all communication systems, and the control center (management system) [SAN 10]. The ICT layer is responsible for collecting information about the state of the grid and of its components from sensors, and sending such data to the control center where all evaluations and possible control actions are assessed. Being the place where all data and information are sent to be processed, and where necessary system response are elaborated, the ADMS can be considered the brain of a smart distribution grid, being, in other terms, what provides actual intell...

Table of contents

• Cover
• Table of Contents
• Dedication
• Title
• Copyright
• Preface
• Introduction: From Smart Grids to the Smart Cities: New Paradigms for Future Networks
• 1 Unbalanced Three-Phase Optimal Power Flow for the Optimization of MV and LV Distribution Grids
• 2 Mixed Integer Linear Programming Models for Network Reconfiguration and Resource Optimization in Power Distribution Networks
• 3 The Role of Nature-inspired Metaheuristic Algorithms for Optimal Voltage Regulation in Urban Smart Grids
• 4 Urban Energy Hubs and Microgrids: Smart Energy Planning for Cities
• 5 Optimization of Multi-energy Carrier Systems in Urban Areas
• 6 Optimal Gas Flow Algorithm for Natural Gas Distribution Systems in Urban Environment
• 7 Multicarrier Energy System Optimal Power Flow
• List of Authors
• Index
• End User License Agreement