Charging Architectures Integrated with Distributed Energy Resources for Sustainable Mobility

Abstract This paper introduces a study on the charging infrastructures, integrated with distributed energy sources, showing their ability to support the electric and hybrid mobility in a smart grid scenario. This analysis starts from a description of the main AC and DC architecture and then goes through the advantages derived by the integration of renewable energy sources within the existing electric power network. A section of this paper is then dedicated to the main technologies of energy storage systems, which allow and support the integration of unpredictable energy sources into the grid. Finally, the power on-board and off-board vehicle charging devices are analyzed with specific focus on PWM control schemes, for the regulation of AC/DC and DC/DC power converters, and on grid operations (V2G) related to different aggregation schemes

Modeling of Electric Vehicles as A Load of the Distribution Grid

Electric vehicles (EVs) are expected to reduce carbon emissions from transportation. For this reason, many vehicle manufacturers, countries and international organizations develop their energy and transportation policies in this direction and also support them with practices. As a result of the policies implemented and developments in battery technologies, serious increases are expected in the sales of the EV sector. However, there should be sufficient charging stations for EV charging. The increase in charging stations is expected to cause some positive and negative effects on the grid. In order for electric vehicles to be more acceptable in terms of power systems, it is necessary to understand what kind of electrical character they show. In this article, EV electrical modeling is performed over a charging period by Monte Carlo Simulation using the actual charging data of some EV models charged in a single phase 7, 2 kW-240 V charger. The generated probabilistic model was validated by comparing it with real data. Thus, a reliable modeling has been presented for EV, which is a new load in power systems

An Ultrafast EV Charging Station Demonstrator

This paper deals with the design of a grid-friendly ultrafast electric vehicle charging demonstrator. High charging power and short charging times impose peaks to an electricity distribution system, which necessitate over-dimensioning of the grid connection. A mitigation option lies in partial decoupling the load from the grid, achieved with the application of energy storage elements. A calculation methodology for energy storage elements is proposed and their interconnection possibilities to an ultrafast EV charging spot discussed

Studi Sistem Pengisian Cepat Baterai Kendaraan Listrik Berbasis Papan Pengendali OpenEVSE

Abstrak– Penelitian ini bertujuan untuk mempelajari sistem pengisian cepat baterai kendaraan listrik dengan menggunakan papan sistem kontrol OpenEVSE. Seiring bertambahnya jumlah kendaraan listrik yang masuk dalam ekosistem energi hijau, maka kebutuhan terhadap stasiun pengisian kendaraan listrik umum (SPKLU) juga meningkat. Kita membutuhkan perangkat pengisi baterai kendaraan listrik yang cepat dan handal, bukan lagi sebuah prototype, karena teknologi ini sudah berkembang pesat sejak satu dekade yang lalu. Sistem pengisian baterai kendaraan listrik ini sudah menggunakan teknlogi fabrikasi yang sangat baik. Teknologi terkini adalah dikembangkannya papan sistem kontrol terpadu yang khusus untuk desain perangkat pengisi baterai kendaraan listrik. Papan sistem ini adalah bersifat open source sehingga bisa dikembangkan sesuai kebutuhan

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

Dynamic Modeling and Real-time Management of a System of EV Fast-charging Stations

Demand for electric vehicles (EVs), and thus EV charging, has steadily increased over the last decade. However, there is limited fast-charging infrastructure in most parts of the world to support EV travel, especially long-distance trips. The goal of this study is to develop a stochastic dynamic simulation modeling framework of a regional system of EV fast-charging stations for real-time management and strategic planning (i.e., capacity allocation) purposes. To model EV user behavior, specifically fast-charging station choices, the framework incorporates a multinomial logit station choice model that considers charging prices, expected wait times, and detour distances. To capture the dynamics of supply and demand at each fast-charging station, the framework incorporates a multi-server queueing model in the simulation. The study assumes that multiple fast-charging stations are managed by a single entity and that the demand for these stations are interrelated. To manage the system of stations, the study proposes and tests dynamic demand-responsive price adjustment (DDRPA) schemes based on station queue lengths. The study applies the modeling framework to a system of EV fast-charging stations in Southern California. The results indicate that DDRPA strategies are an effective mechanism to balance charging demand across fast-charging stations. Specifically, compared to the no DDRPA scheme case, the quadratic DDRPA scheme reduces average wait time by 26%, increases charging station revenue (and user costs) by 5.8%, while, most importantly, increasing social welfare by 2.7% in the base scenario. Moreover, the study also illustrates that the modeling framework can evaluate the allocation of EV fast-charging station capacity, to identify stations that require additional chargers and areas that would benefit from additional fast-charging stations

Three-Phase Unfolding Based Soft DC-Link Converter Topologies for AC to DC Applications

Battery electric vehicles (BEVs) and plugin hybrid electric vehicles (PHEVs) are more efficient than internal combustion-based vehicles. Adaption of EVs will help reduce the carbon emissions produced by the transportation sector. The charging infrastructure has to grow at a rapid pace to encourage EV adaption. Installing higher capacity fast chargers will help alleviate the range anxiety of battery electric vehicle customers. More public charging stations are required for the full adaption of EVs. Utility power is distributed as ‘alternating current.’ A battery requires ‘direct current’ (DC) source to charge it. Hence a power converter that converts AC source to DC source is required to charge an electric vehicle battery. Public transportation is another sector that is adapting electric vehicles at a fast pace. These vehicles require more power to operate and hence have huge battery packs. These vehicles require ultra-high-power charger to keep the charging time reasonable. A 60 Hz stepdown transformer is required at the facility to use the power. The cost and time to install this heavy transformer will inhibit the setting up a charging station. Power converters than can connect to medium voltage directly will eliminate the need for the step-down transformer saving space and cost. Commercially available state-of-the-art fast charging converters are adapted from general purpose commercial and industrial application rectifiers. The efficiencies of these converters tend to be lower (around 94%) due to the two-stage power conversion architecture. All the power that flows from the AC utility grid to charge the battery will be processed and filtered through two power conversion stages. Due to the anticipated increase in demand, there is a renewed interest in developing power converter topologies specific to battery charging applications. The objective here is to develop cheaper and compact power converters for battery charging. This dissertation proposes an innovative quasi-single stage power converter topologies for battery charging applications and direct medium voltage connected converters. The proposed topology fundamentally can achieve higher efficiency and power density than the conventional two-stage based converters. Only one stage requires filtering and incurs power conversion losses. Control burden is usually higher for single stage topologies. Innovative control approaches are presented to simplify the control complexity