Giovanni Brusco

Energy Management System for an Energy District With Demand Response Availability

During recent years the electricity supply chain (electricity production, consumption, distribution, storage, and load management) has changed. In this context a new term appears: the prosumer, that is both a consumer and producer of energy in the same entity. In the paper, an energy management approach of several prosumers aggregated in a coalition, the energy district (ED), and coordinated through a central control entity, the coalition coordinator, is proposed. The aim of the coalition coordinator is to maximize the coalition utility also reducing in this way the reverse energy flows at the point of delivery by an appropriate demand response program. The application on an Italian residential housing area is illustrated. The numerical results demonstrate the effectiveness and attractiveness of the proposed energy management scheme.

An incremental conductance method with variable step size for MPPT: Design and implementation

In this paper the authors propose a novel method for tracking the maximum power point of a PV array. This method is derived by the well known incremental conductance method and the novelty consists in varying the duty cycle of the dc-dc switching converter used as MPPT tracker using a variable step size instead of a fixed step size. A practical way to determine the minimum and the maximum values of the variable step size is explained in detail. The laboratory results demonstrate the effectiveness of the proposed method both in terms of speed in MPP tracking and accuracy in the MPP individuation.

In the future Smart Cities: Coordination of micro Smart Grids in a Virtual Energy District

In the future Smart City, new information and communication technologies will enable a better management of the available resources. The Smart Grid infrastructure is emerging as a complex system where fine-grained monitoring and control of energy generating and/or consuming entities within the electricity network is possible. This will result to better approaches that will boost energy efficiency. To make real this vision, (open) platforms providing access to the smart meter data as well as potential management and value-added functionalities are needed. These will offer basic energy services that can be commonly used by application developers. In this context, this paper proposes a new market platform in order to coordinate the energy exchanges among several micro Smart Grids aggregated in a Virtual Energy District. Some numerical results in Matlab/Simulink environment are presented to validate the proposed platform.

Implementation of a novel fuzzy-logic based MPPT for grid-connected photovoltaic generation system

This paper presents modeling and simulation of a grid connected photovoltaic (PV) generation system with maximum power point tracking (MPPT) using a novel fuzzy logic controller (FLC). The system is composed of a PV array, boost converter with MPPT and a single phase inverter connected to utility grid. The MPPT is based on fuzzy logic to control IGBT switch of the boost converter. The performance of the proposed FLC for MPPT is evaluated by simulation and the results show that the FLC is more efficient in finding the maximum power point than the conventional incremental conductance method when the PV system is subjected to variations in external operating conditions (insulation level and module temperature).

Design of a grid-connected Photovoltaic system with grid ancillary services

Over the last decade, various reasons have determined a continuous increase of grid-connected photovoltaic systems due to need of supplying the world rise demand for electric power. This gave rise to problems concerning the stability and safety of the utility grid as well as power quality issues. It has drastically changed the way in which the grid-connected photovoltaic systems should interact with the grid. In this context the purpose of this paper it is proposed a control methodology using the active and reactive power control strategy proposed by the authors in a previous paper in order to provide ancillary services to the grid to safeguard the reliability, the stability and the power quality of the electrical system. The simulations has been carry-out using Matlab/Simulink environment, demonstrating that the proposed control methodology is able to provide grid ancillary services according to a grid interconnection standard.

Demand response program implementation in an energy district of domestic prosumers

During the last years the electricity supply chain (the production, consumption, distribution, storage and load management of electricity) has changed. In this contest a new term appears: the prosumer, that is a consumer and a producer of energy in the same entity. In the paper, a demand response program is proposed considering several prosumers combined into an Energy District connected through a central control entity: an aggregator. The goal of aggregator is to minimize the reverse energy flowing at the MV/LV substation minimizing the energy costs of the Energy district. The application on a Italian residential housing area is illustrated.

A Smartbox as a low-cost home automation solution for prosumers with a battery storage system in a demand response program

On the basis that a processing resource optimally calculates the loads scheduling one day-ahead for those prosumers operating in a demand response program, the question is: who acts the scheduling? This paper presents an electronic device named Smartbox as a low-cost and feasible home automation solution; so, given a processing resource which optimally calculates the loads scheduling one day-ahead, the mission of the Smartbox is receive and act the loads scheduling. The processing resource is in the cloud computing and it calculates the optimal scheduling through the solution of a prosumer problem so to minimizes the electricity bill; such a load scheduling is sent to the Smartbox via Internet. The Smartbox receives the load scheduling and hourly sends commands to local schedulable loads through an existing home automation system. In order to demonstrate the effectiveness and the feasibility of the proposed Smartbox, a prototype using an Arduino MEGA 2560 has been realized and tested in the laboratory. Such a prototype has been tested in combination with a) a software application consisting in a Java program which serves the user for input data, b) a prosumer problem solver consisting in a personal computer with Matlab and c) a demonstration panel which represents a private household equipped with a Schneider Electric - Konnex protocol home automation system. The laboratory test demonstrate that the Smartbox prototype is genuinely effective in implementing the load scheduling because duly and correctly the Smartbox manages the switching-on and off of schedulable loads.

A feed-in tariff to favorite photovoltaic and batteries energy storage systems for grid-connected consumers

The paper proposes a feed-in tariff policy to favorite the adoption of systems which combine a photovoltaic system and a battery energy storage system. A simple optimization problem is also proposed to sizing jointly the PV and the BESS. The effectiveness of the proposed policy is evaluated using software simulations; the energy consumption of a real consumer, over each 15 minutes and covering 2011, is considered. The optimal solution is investigated further in terms of cash flows and life of the batteries. Numerical results demonstrate the feasibility of the proposed policy.

A multiperiodal management method at user level for storage systems using artificial neural network forecasts

The increase of renewable non-programmable production and the necessity to locally self-consume the produced energy led to utilize ever more storage systems. To correctly utilize storage systems, an opportune management method has to be utilized. This paper implements a multi-period management method for storage devices, using different management strategies. The method aims to minimize the total absorbed and supplied energy or the peak power exchanged with the grid. The results show the effectiveness of the method in diminishing the energy exchanged with the grid and also the possibility to optimize the performance of the storage device.

A dual active bridge dc-dc converter for application in a smart user network

The paper presents a dual active bridge converter, i.e. an isolated bidirectional DC/DC converter composed of two full-bridge DC/AC converters and an isolation high frequency (HF) transformer, useful for application in a DC-powered microgrid. The dual active bridge converter connects a battery energy storage system to a DC bus so to provide a high level of reliability and resilience to grid disturbances. In particular, the proposed converter ensures a stable DC bus voltage when the microgrid is operated in islanded mode. Numerical results demonstrate the good dynamic response of the converter under transient condition of a step change in power balancing condition.