Electric Vehicles Charging Technology Review and Optimal Size Estimation

AbstractMany different types of electric vehicle (EV) charging technologies are described in literature and implemented in practical applications. This paper presents an overview of the existing and proposed EV charging technologies in terms of converter topologies, power levels, power flow directions and charging control strategies. An overview of the main charging methods is presented as well, particularly the goal is to highlight an effective and fast charging technique for lithium ions batteries concerning prolonging cell cycle life and retaining high charging efficiency. Once presented the main important aspects of charging technologies and strategies, in the last part of this paper, through the use of genetic algorithm, the optimal size of the charging systems is estimated and, on the base of a sensitive analysis, the possible future trends in this field are finally valued

numerical simulation analysis of the impact of photovoltaic systems and energy storage technologies on centralised generation a case study for australia

In response to climate change concerns, most of the industrialised countries have committed in recent years to increase their share of Renewable Energy Sources to reduce Greenhouse Gas emissions. Therefore, the rapid deployment of small-scale photovoltaic (PV) systems, mainly in residential applications, is starting to represent a considerable portion of the available electrical power generation and, for this reason, the stochastic and intermittent nature of these systems are affecting the operation of centralised generation (CG) resources. Network operators are constantly changing their approach to both short-term and long-term forecasting activities due to the higher complexity of the scenario in which more and more stakeholders have active roles in the network. An increasing number of customers must be treated as prosumers and no longer only as consumers. In this context, storage technologies are considered the suitable solution. These can be necessary in order to solve and fill the problems of the renewable distributed sources are introducing in the management of the network infrastructure. The aim of this work was to create a model in order to evaluate the impact of power generation considering PV systems in Australia along with a model to simulate Battery Energy Storage Systems (BESSs) and Electric Vehicles future contributions using MATLAB. The methodology used to develop these models was based on statistical assumptions concerning the available details about PV systems installed and current storage technologies. It has been shown that in all the scenarios analysed, the future adoption of rooftop PV panels and impact on the CG is incredibly higher than the uptake of energy storage systems. Hence, the influence on the demand will be driven by the behaviour of the PV systems. Only in the hypothetical scenario in which the installations of BESSs will assume comparable levels of the PV systems, it will be possible to better manage the centralised resources

Transient Analysis of Large Scale PV Systems with Floating DC Section

The increasing penetration of renewable sources with power-electronic interfaces in power systems is raising technical problems and the overall efficiency of photovoltaic systems can decrease dramatically. In this context, the optimal layout for the photovoltaic system is required. The most adequate strategy to connect the renewable system to the electrical power grid or to supply the end users must be adopted. The present paper proposes a design layout of a PV plant using a DC bus system to improve the overall energy conversion efficiency. An analysis of steady-state system stability, voltage drop and DC cable conduction losses is conducted. The leakage currents to the ground are investigated through simulations. Experimental results are shown focused on the analysis of optimal layout of photovoltaic systems under particular operating conditions

Collective water transport electrification: Venetian ferry boat case study

This paper studies and analyzes the energy transition of ferry boats used in Venice as a means of public transportation. Thus, the goal is to reduce their environmental impact by replacing the current installed thermal propulsion with an equivalent low-emission electric type. A study was conducted aimed at sizing the most suitable electric motor and battery pack to be installed, as well as the most suitable charging system for the vehicle and the area involved in this case study. The shift to electric traction will bring new challenges for the service, but also the possibility to decarbonize the water transport in Venice, preserving air quality and the monuments of the UNESCO site. Therefore, it is noted how these changes may impact service delivery

Experimental investigation of PQ impact of different lighting systems in railway stations

New lighting technologies are very important for their overall efficiency in reducing the absorbed energy and the operating and maintenance costs. However, they can introduce Power Quality (PQ) problems such as harmonic distortions, losses on the grid and power factor. This paper presents the results of an experimental investigation on power and harmonic absorption of different outdoor lamps (LED and gas discharge lamps), supplied by different ballasts, used in a railway station. The PQ and harmonic analysis is based on the indexes reported in the IEEE Trial use standard definitions for measurement of electric power

Optimal locating of electric vehicle charging stations by application of Genetic Algorithm

The advent of alternative vehicle technologies such as Electrical Vehicles (EVs) is an efficient effort to reduce the emission of carbon oxides and nitrogen oxides. Ironically, EVs poses concerns related to vehicle recharging and management. Due to the significance of charging station infrastructure, electric vehicles' charging stations deployment is investigated in this work. Its aim is to consider several limitations such as the power of charging station, the average time needed for each recharge, and traveling distance per day. Initially, a mathematical formulation of the problem is framed. Then, this problem is optimized by application of Genetic Algorithm (GA), with the objective to calculate the necessary number of charging stations then finding the best positions to locate them to satisfy the clients demand

Application of genetic algorithms for driverless subway train energy optimization

After an introduction on the basic aspects of electric railway transports, focusing mainly on driverless subways and their related automation systems (ATC, ATP, and ATO), a technique for energy optimization of the train movement through their control using genetic algorithms will be presented. Genetic algorithms are a heuristic search and iterative stochastic method used in computing to find exact or approximate solutions to optimization problems. This optimization process has been calculated and tested on a real subway line in Milan through the implementation of a dedicated Matlab code. The so-defined algorithm provides the optimization of the trains movement through a coast control table created by the use of a genetic algorithm that minimizes the energy consumption and the train scheduled time. The obtained results suggest that the method is promising in minimizing the energy consumption of the electric trains

Integration and optimization of renewables and storages for rural electrification

The electricity access in Sub-Saharan African countries is below 10%; thus, introducing a microgrid for rural electrification can overcome the endemic lack of modern electricity access that hampers the provision of basic services such as education, healthcare, safety, economic and social growth for rural communities. This work studies different possible comparison methods considering variations such as land area required, location for the storage, efficiency, availability and reliability of energy resources, and technology cost variability (investment cost and levelized cost of electricity), which are among the major key parameters used to assess the best possible utilization of renewables and storage system, either using them in the form of integrated, hybrid or independent systems. The study is carried out largely with the help of the Micropower optimization modeling simulator called HOMER for Ethiopia. As a result, the study proposes the use of Photovoltaic (PV)-Wind-Hydro-Battery hybrid system model that concludes the optimal configuration of power systems at affordable price for underserved rural communities