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Special Issue "Energy Storage Systems and Power Conversion Electronics for E-Transportation and Smart Grid"

A special issue of Energies (ISSN 1996-1073).

Deadline for manuscript submissions: closed (31 July 2018)

Special Issue Editors

Guest Editor
Prof. Dr. Sergio Saponara

Dip. Ingegneria Informazione (DII), University of Pisa, via G. Caruso 16, 56122, Pisa, Italy
Website | E-Mail
Interests: power electronics; integrated power converters; electric/hybrid-vehicles; smart energy systems; energy storage systems; predictive diagnostics
Guest Editor
Prof. Dr. Lucian Mihet

Faculty of Engineering, Østfold University College, Kobberslagerstredet 5, 1671 Kråkeroy-Fredrikstad, Norway
Website | E-Mail
Phone: +4792271353
Interests: Modelling, simulations, control and testing of DER components (including BESS) in Power Distribution Systems (Micro-Grids, Smart Grids); Integration of DGs and renewable energy sources including PV, EV and BESS

Special Issue Information

Dear Colleagues,

We are inviting submissions to a Special Issue of Energies entitled “Energy Storage Systems and Power Conversion Electronics for E-Transportation and Smart Grid”.

Research and technology transfer activities in energy storage systems, such as batteries and super/ultra-capacitors is essential for the success of electric transportation and to foster the use of renewable energy sources. Indeed, renewable energy sources are intermittent in nature and are not directly matched with users’ requirements. Energy storage systems are the key technology to solve these issues and to increase the adoption of renewable energy sources in the smart grid.

However, major challenges have still to be solved such as the design of high performance and cost-effective energy storage systems, the on-line estimation of state-of-charge/state-of-health of batteries and super/ultra-capacitors, the estimation of aging effects, the design and optimization of fast chargers and the integration within the smart grid of the charging infrastructure for e-transportation.

Power converters need also optimization in terms of increased efficiency and implementation of predictive diagnostic features. Beside the hardware parts, also the role of the software is increasing and new design and verification methods have to be investigated to achieve high functional safety levels.

The main objective of this Special Issue is, hence, to provide timely solutions for the design and management of energy storage systems, of renewable energy sources and of the relevant power electronics conversion systems.

Integration of all these systems within the smart grid for e-transportation and smart/green cities is also of interest for the special issue. With reference to this “internet of energy” scenario the application of IoT (Internet of things) technologies to the E-transportation and smart grid is also of interest.

The particular topics of interest include, but are not limited to:

  • New emerging energy storage technologies
  • Ageing mechanisms of power converters and energy storage devices
  • Electronic control units for energy storage system monitoring and management
  • Online estimation of state-of-charge and state-of-health
  • Power conversion electronics for renewable energy sources
  • Fast chargers and smart chargers for electric-vehicles
  • Integration of charging infrastructures in the smart grid for E-transportation
  • Predictive diagnostic for renewable energy sources and energy storage systems
  • Methods for design and verification of hardware and software for energy storage and renewable energy systems
  • Integration of IoT into E-transportation

Prof. Dr. Sergio Saponara
Prof. Dr. Lucian Mihet
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All papers will be peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Energies is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 1600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • emerging energy storage technologies
  • ageing of energy storage and power converters
  • monitoring & management of energy storage systems
  • power conversion electronics
  • renewable energy sources
  • E-transportation chargers and smart-grid
  • internet-of-energy

Published Papers (19 papers)

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Research

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Open AccessArticle Hybrid PV-Wind, Micro-Grid Development Using Quasi-Z-Source Inverter Modeling and Control—Experimental Investigation
Energies 2018, 11(9), 2277; https://doi.org/10.3390/en11092277
Received: 2 June 2018 / Revised: 16 August 2018 / Accepted: 21 August 2018 / Published: 29 August 2018
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Abstract
This research work deals with the modeling and control of a hybrid photovoltaic (PV)-Wind micro-grid using Quasi Z-source inverter (QZsi). This inverter has major benefits as it provides better buck/boost characteristics, can regulate the phase angle output, has less harmonic contents, does not
[...] Read more.
This research work deals with the modeling and control of a hybrid photovoltaic (PV)-Wind micro-grid using Quasi Z-source inverter (QZsi). This inverter has major benefits as it provides better buck/boost characteristics, can regulate the phase angle output, has less harmonic contents, does not require the filter and has high power performance characteristics over the conventional inverter. A single ended primary inductance converter (SEPIC) module used as DC-DC switched power apparatus is employed for maximum power point tracking (MPPT) functions which provide high voltage gain throughout the process. Moreover, a modified power ratio variable step (MPRVS) based perturb & observe (P&O) method has been proposed, as part of the PV MPPT action, which forces the operating point close to the maximum power point (MPP). The proposed controller effectively correlates with the hybrid PV, Wind and battery system and provides integration of distributed generation (DG) with loads under varying operating conditions. The proposed standalone micro grid system is applicable specifically in rural places. The dSPACE real-time hardware platform has been employed to test the proposed micro grid system under varying wind speed, solar irradiation, load cutting and removing conditions etc. The experimental results based on a real-time digital platform, under dynamic conditions, justify the performance of a hybrid PV-Wind micro-grid with Quasi Z-Source inverter topology. Full article
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Open AccessArticle An Overview of Energy Scenarios, Storage Systems and the Infrastructure for Vehicle-to-Grid Technology
Energies 2018, 11(8), 2174; https://doi.org/10.3390/en11082174
Received: 21 June 2018 / Revised: 7 August 2018 / Accepted: 13 August 2018 / Published: 20 August 2018
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Abstract
The increase in the emission of greenhouse gases (GHG) is one of the most important problems in the world. Decreasing GHG emissions will be a big challenge in the future. The transportation sector uses a significant part of petroleum production in the world,
[...] Read more.
The increase in the emission of greenhouse gases (GHG) is one of the most important problems in the world. Decreasing GHG emissions will be a big challenge in the future. The transportation sector uses a significant part of petroleum production in the world, and this leads to an increase in the emission of GHG. The result of this issue is that the population of the world befouls the environment by the transportation system automatically. Electric Vehicles (EV) have the potential to solve a big part of GHG emission and energy efficiency issues such as the stability and reliability of energy. Therefore, the EV and grid relation is limited to the Vehicle-to-Grid (V2G) or Grid-to-Vehicle (G2V) function. Consequently, the grid has temporary energy storage in EVs’ batteries and electricity in exchange for fossil energy in vehicles. The energy actors and their research teams have determined some targets for 2050; hence, they hope to decrease the world temperature by 6 °C, or at least by 2 °C in the normal condition. Fulfilment of these scenarios requires suitable grid infrastructure, but in most countries, the grid does not have a suitable background to apply in those scenarios. In this paper, some problems regarding energy scenarios, energy storage systems, grid infrastructure and communication systems in the supply and demand side of the grid are reviewed. Full article
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Open AccessArticle Maximum Power Point Tracking for Brushless DC Motor-Driven Photovoltaic Pumping Systems Using a Hybrid ANFIS-FLOWER Pollination Optimization Algorithm
Energies 2018, 11(5), 1067; https://doi.org/10.3390/en11051067
Received: 18 March 2018 / Revised: 21 April 2018 / Accepted: 24 April 2018 / Published: 26 April 2018
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Abstract
In this research paper, a hybrid Artificial Neural Network (ANN)-Fuzzy Logic Control (FLC) tuned Flower Pollination Algorithm (FPA) as a Maximum Power Point Tracker (MPPT) is employed to amend root mean square error (RMSE) of photovoltaic (PV) modeling. Moreover, Gaussian membership functions have
[...] Read more.
In this research paper, a hybrid Artificial Neural Network (ANN)-Fuzzy Logic Control (FLC) tuned Flower Pollination Algorithm (FPA) as a Maximum Power Point Tracker (MPPT) is employed to amend root mean square error (RMSE) of photovoltaic (PV) modeling. Moreover, Gaussian membership functions have been considered for fuzzy controller design. This paper interprets the Luo converter occupied brushless DC motor (BLDC)-directed PV water pump application. Experimental responses certify the effectiveness of the suggested motor-pump system supporting diverse operating states. The Luo converter, a newly developed DC-DC converter, has high power density, better voltage gain transfer and superior output waveform and can track optimal power from PV modules. For BLDC speed control there is no extra circuitry, and phase current sensors are enforced for this scheme. The most recent attempt using adaptive neuro-fuzzy inference system (ANFIS)-FPA-operated BLDC directed PV pump with advanced Luo converter, has not been formerly conferred. Full article
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Open AccessArticle Boundary Detection and Enhancement Strategy for Power System Bus Bar Stabilization—Investigation under Fault Conditions for Islanding Operation
Energies 2018, 11(4), 889; https://doi.org/10.3390/en11040889
Received: 9 December 2017 / Revised: 31 December 2017 / Accepted: 4 January 2018 / Published: 11 April 2018
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Abstract
Distribution systems can form islands when faults occur. Each island represents a subsection with variable boundaries subject to the location of fault(s) in the system. A subsection with variable boundaries is referred to as an island in this paper. For operation in autonomous
[...] Read more.
Distribution systems can form islands when faults occur. Each island represents a subsection with variable boundaries subject to the location of fault(s) in the system. A subsection with variable boundaries is referred to as an island in this paper. For operation in autonomous mode, it is imperative to detect the island configurations and stabilize these subsections. This paper presents a novel scheme for the detection of island boundaries and stabilizing the system during autonomous operation. In the first stage, a boundary detection method is proposed to detect the configuration of the island. In the second stage, a dynamic voltage sensitivity factor (DVSF) is proposed to assess the dynamic performance of the system. In the third stage, a wide area load shedding program is adopted based on DVSF to shed the load in weak bus-bars and stabilize the system. The proposed scheme is validated and tested on a generic 18-bus system using a combination of EMTDC/PSCAD and MATLAB software’s. Full article
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Open AccessArticle An Original Transformer and Switched-Capacitor (T & SC)-Based Extension for DC-DC Boost Converter for High-Voltage/Low-Current Renewable Energy Applications: Hardware Implementation of a New T & SC Boost Converter
Energies 2018, 11(4), 783; https://doi.org/10.3390/en11040783
Received: 25 September 2017 / Revised: 2 November 2017 / Accepted: 6 November 2017 / Published: 29 March 2018
Cited by 2 | PDF Full-text (10112 KB) | HTML Full-text | XML Full-text
Abstract
In this article a new Transformer and Switched Capacitor-based Boost Converter (T & SC-BC) is proposed for high-voltage/low-current renewable energy applications. The proposed T & SC-BC is an original extension for DC-DC boost converter which is designed by utilizing a transformer and switched
[...] Read more.
In this article a new Transformer and Switched Capacitor-based Boost Converter (T & SC-BC) is proposed for high-voltage/low-current renewable energy applications. The proposed T & SC-BC is an original extension for DC-DC boost converter which is designed by utilizing a transformer and switched capacitor (T & SC). Photovoltaic (PV) energy is a fast emergent segment among the renewable energy systems. The proposed T & SC-BC combines the features of the conventional boost converter and T & SC to achieve a high voltage conversion ratio. A Maximum Power Point Tracking (MPPT) controller is compulsory and necessary in a PV system to extract maximum power. Thus, a photovoltaic MPPT control mechanism also articulated for the proposed T & SC-BC. The voltage conversion ratio (Vo/Vin) of proposed converter is (1 + k)/(1 − D) where, k is the turns ratio of the transformer and D is the duty cycle (thus, the converter provides 9.26, 13.88, 50/3 voltage conversion ratios at 78.4 duty cycle with k = 1, 2, 2.6, respectively). The conspicuous features of proposed T & SC-BC are: (i) a high voltage conversion ratio (Vo/Vin); (ii) continuous input current (Iin); (iii) single switch topology; (iv) single input source; (v) low drain to source voltage (VDS) rating of control switch; (vi) a single inductor and a single untapped transformer are used. Moreover, the proposed T & SC-BC topology was compared with recently addressed DC-DC converters in terms of number of components, cost, voltage conversion ratio, ripples, efficiency and power range. Simulation and experimental results are provided which validate the functionality, design and concept of the proposed approach. Full article
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Open AccessArticle Sliding Mode Controller and Lyapunov Redesign Controller to Improve Microgrid Stability: A Comparative Analysis with CPL Power Variation
Energies 2017, 10(12), 1959; https://doi.org/10.3390/en10121959
Received: 11 September 2017 / Revised: 13 October 2017 / Accepted: 25 October 2017 / Published: 24 November 2017
Cited by 4 | PDF Full-text (10852 KB) | HTML Full-text | XML Full-text
Abstract
To mitigate the microgrid instability despite the presence of dense Constant Power Load (CPL) loads in the system, a number of compensation techniques have already been gone through extensive research, proposed, and implemented around the world. In this paper, a storage based load
[...] Read more.
To mitigate the microgrid instability despite the presence of dense Constant Power Load (CPL) loads in the system, a number of compensation techniques have already been gone through extensive research, proposed, and implemented around the world. In this paper, a storage based load side compensation technique is used to enhance stability of microgrids. Besides adopting this technique here, Sliding Mode Controller (SMC) and Lyapunov Redesign Controller (LRC), two of the most prominent nonlinear control techniques, are individually implemented to control microgrid system stability with desired robustness. CPL power is then varied to compare robustness of these two control techniques. This investigation revealed the better performance of the LRC system compared to SMC to retain stability in microgrid with dense CPL load. All the necessary results are simulated in Matlab/Simulink platform for authentic verification. Reasons behind inferior SMC performance and ways to mitigate that are also discussed. Finally, the effectiveness of SMC and LRC systems to attain stability in real microgrids is verified by numerical analysis. Full article
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Open AccessArticle Minimization of Load Variance in Power Grids—Investigation on Optimal Vehicle-to-Grid Scheduling
Energies 2017, 10(11), 1880; https://doi.org/10.3390/en10111880
Received: 16 September 2017 / Revised: 30 October 2017 / Accepted: 3 November 2017 / Published: 16 November 2017
Cited by 3 | PDF Full-text (7388 KB) | HTML Full-text | XML Full-text
Abstract
The introduction of electric vehicles into the transportation sector helps reduce global warming and carbon emissions. The interaction between electric vehicles and the power grid has spurred the emergence of a smart grid technology, denoted as vehicle-to grid-technology. Vehicle-to-grid technology manages the energy
[...] Read more.
The introduction of electric vehicles into the transportation sector helps reduce global warming and carbon emissions. The interaction between electric vehicles and the power grid has spurred the emergence of a smart grid technology, denoted as vehicle-to grid-technology. Vehicle-to-grid technology manages the energy exchange between a large fleet of electric vehicles and the power grid to accomplish shared advantages for the vehicle owners and the power utility. This paper presents an optimal scheduling of vehicle-to-grid using the genetic algorithm to minimize the power grid load variance. This is achieved by allowing electric vehicles charging (grid-to-vehicle) whenever the actual power grid loading is lower than the target loading, while conducting electric vehicle discharging (vehicle-to-grid) whenever the actual power grid loading is higher than the target loading. The vehicle-to-grid optimization algorithm is implemented and tested in MATLAB software (R2013a, MathWorks, Natick, MA, USA). The performance of the optimization algorithm depends heavily on the setting of the target load, power grid load and capability of the grid-connected electric vehicles. Hence, the performance of the proposed algorithm under various target load and electric vehicles’ state of charge selections were analysed. The effectiveness of the vehicle-to-grid scheduling to implement the appropriate peak load shaving and load levelling services for the grid load variance minimization is verified under various simulation investigations. This research proposal also recommends an appropriate setting for the power utility in terms of the selection of the target load based on the electric vehicle historical data. Full article
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Open AccessArticle Hardware Implementation and a New Adaptation in the Winding Scheme of Standard Three Phase Induction Machine to Utilize for Multifunctional Operation: A New Multifunctional Induction Machine
Energies 2017, 10(11), 1757; https://doi.org/10.3390/en10111757
Received: 23 July 2017 / Revised: 22 October 2017 / Accepted: 23 October 2017 / Published: 1 November 2017
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Abstract
In this article a new distinct winding scheme is articulated to utilize three phase induction machines for multifunctional operation. Because of their rugged construction and reduced maintenance induction machines are very popular and well-accepted for agricultural as well as industrial purposes. The proposed
[...] Read more.
In this article a new distinct winding scheme is articulated to utilize three phase induction machines for multifunctional operation. Because of their rugged construction and reduced maintenance induction machines are very popular and well-accepted for agricultural as well as industrial purposes. The proposed winding scheme is used in a three phase induction machine to utilize the machine for multifunctional operation. It can be used as a three-phase induction motor, welding transformer and phase converter. The proposed machine design also works as a single phase induction motor at the same time it works as a three-phase to single phase converter. This new design does not need any kind of special arrangement and can be constructed with small modifications to any standard three-phase induction motor. This modified induction machine is thoroughly tested to determine its efficiency and other parameters and also hardware implementation results are provided in the article, which validate the design and construction. Full article
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Open AccessArticle Development of Sliding Mode Controller for a Modified Boost Ćuk Converter Configuration
Energies 2017, 10(10), 1513; https://doi.org/10.3390/en10101513
Received: 18 June 2017 / Revised: 11 July 2017 / Accepted: 13 July 2017 / Published: 29 September 2017
Cited by 2 | PDF Full-text (5642 KB) | HTML Full-text | XML Full-text
Abstract
This paper introduces a sliding mode control (SMC)-based equivalent control method to a novel high output gain Ćuk converter. An additional inductor and capacitor improves the efficiency and output gain of the classical Ćuk converter. Classical proportional integral (PI) controllers are widely used
[...] Read more.
This paper introduces a sliding mode control (SMC)-based equivalent control method to a novel high output gain Ćuk converter. An additional inductor and capacitor improves the efficiency and output gain of the classical Ćuk converter. Classical proportional integral (PI) controllers are widely used in direct current to direct current (DC-DC) converters. However, it is a very challenging task to design a single PI controller operating in different loads and disturbances. An SMC-based equivalent control method which achieves a robust operation in a wide operation range is also proposed. Switching frequency is kept constant in appropriate intervals at different loading and disturbance conditions by implementing a dynamic hysteresis control method. Numerical simulations conducted in MATLAB/Simulink confirm the accuracy of analysis of high output gain modified Ćuk converter. In addition, the proposed equivalent control method is validated in different perturbations to demonstrate robust operation in wide operation range. Full article
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Open AccessArticle Coordinated Control Strategies for a Permanent Magnet Synchronous Generator Based Wind Energy Conversion System
Energies 2017, 10(10), 1493; https://doi.org/10.3390/en10101493
Received: 19 June 2017 / Revised: 21 July 2017 / Accepted: 14 August 2017 / Published: 28 September 2017
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Abstract
In this paper, a novel co-ordinated hybrid maximum power point tracking (MPPT)-pitch angle based on a radial basis function network (RBFN) is proposed for a variable speed variable pitch wind turbine. The proposed controller is used to maximise output power when the wind
[...] Read more.
In this paper, a novel co-ordinated hybrid maximum power point tracking (MPPT)-pitch angle based on a radial basis function network (RBFN) is proposed for a variable speed variable pitch wind turbine. The proposed controller is used to maximise output power when the wind speed is low and optimise the power when the wind speed is high. The proposed controller provides robustness to the nonlinear characteristic of wind speed. It uses wind speed, generator speed, and generator power as input variables and utilises the duty cycle and the reference pitch angle as the output control variables. The duty cycle is used to control the converter so as to maximise the power output and the reference pitch angle is used to control the generator speed in order to control the generator output power in the above rated wind speed region. The effectiveness of the proposed controller was verified using MATLAB/Simulink software. Full article
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Open AccessArticle Study and Analysis of an Intelligent Microgrid Energy Management Solution with Distributed Energy Sources
Energies 2017, 10(9), 1419; https://doi.org/10.3390/en10091419
Received: 11 July 2017 / Revised: 12 September 2017 / Accepted: 12 September 2017 / Published: 16 September 2017
Cited by 7 | PDF Full-text (8381 KB) | HTML Full-text | XML Full-text
Abstract
In this paper, a robust energy management solution which will facilitate the optimum and economic control of energy flows throughout a microgrid network is proposed. The increased penetration of renewable energy sources is highly intermittent in nature; the proposed solution demonstrates highly efficient
[...] Read more.
In this paper, a robust energy management solution which will facilitate the optimum and economic control of energy flows throughout a microgrid network is proposed. The increased penetration of renewable energy sources is highly intermittent in nature; the proposed solution demonstrates highly efficient energy management. This study enables precise management of power flows by forecasting of renewable energy generation, estimating the availability of energy at storage batteries, and invoking the appropriate mode of operation, based on the load demand to achieve efficient and economic operation. The predefined mode of operation is derived out of an expert rule set and schedules the load and distributed energy sources along with utility grid. Full article
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Open AccessArticle A Modular AC-DC Power Converter with Zero Voltage Transition for Electric Vehicles
Energies 2017, 10(9), 1386; https://doi.org/10.3390/en10091386
Received: 9 August 2017 / Revised: 3 September 2017 / Accepted: 8 September 2017 / Published: 12 September 2017
Cited by 1 | PDF Full-text (9283 KB) | HTML Full-text | XML Full-text
Abstract
A study of the fundamental of operation of a three-phase AC-DC power converter that uses Zero-Voltage Transition (ZVT) together with Space Vector Pulse Width Modulation (SVPWM) is presented. The converter is basically an active rectifier divided into two converters: a matrix converter and
[...] Read more.
A study of the fundamental of operation of a three-phase AC-DC power converter that uses Zero-Voltage Transition (ZVT) together with Space Vector Pulse Width Modulation (SVPWM) is presented. The converter is basically an active rectifier divided into two converters: a matrix converter and an H bridge, which transfer energy through a high-frequency transformer, resulting in a modular AC-DC wireless converter appropriate for Plug-in Electric Vehicles (PEVs). The principle of operation of this converter considers high power quality, output regulation and low semiconductor power loss. The circuit operation, idealized waveforms and modulation strategy are explained together with simulation results of a 5 kW design. Full article
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Open AccessArticle Interconnecting Microgrids via the Energy Router with Smart Energy Management
Energies 2017, 10(9), 1297; https://doi.org/10.3390/en10091297
Received: 14 July 2017 / Revised: 26 August 2017 / Accepted: 28 August 2017 / Published: 30 August 2017
Cited by 2 | PDF Full-text (3484 KB) | HTML Full-text | XML Full-text
Abstract
A novel and flexible interconnecting framework for microgrids and corresponding energy management strategies are presented, in response to the situation of increasing renewable-energy penetration and the need to alleviate dependency on energy storage equipment. The key idea is to establish complementary energy exchange
[...] Read more.
A novel and flexible interconnecting framework for microgrids and corresponding energy management strategies are presented, in response to the situation of increasing renewable-energy penetration and the need to alleviate dependency on energy storage equipment. The key idea is to establish complementary energy exchange between adjacent microgrids through a multiport electrical energy router, according to the consideration that adjacent microgrids may differ substantially in terms of their patterns of energy production and consumption, which can be utilized to compensate for each other’s instant energy deficit. Based on multiport bidirectional voltage source converters (VSCs) and a shared direct current (DC) power line, the energy router serves as an energy hub, and enables flexible energy flow among the adjacent microgrids and the main grid. The analytical model is established for the whole system, including the energy router, the interconnected microgrids and the main grid. Various operational modes of the interconnected microgrids, facilitated by the energy router, are analyzed, and the corresponding control strategies are developed. Simulations are carried out on the Matlab/Simulink platform, and the results have demonstrated the validity and reliability of the idea for microgrid interconnection as well as the corresponding control strategies for flexible energy flow. Full article
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Open AccessArticle Modelling and Simulation of Electric Vehicle Fast Charging Stations Driven by High Speed Railway Systems
Energies 2017, 10(9), 1268; https://doi.org/10.3390/en10091268
Received: 26 June 2017 / Revised: 2 August 2017 / Accepted: 10 August 2017 / Published: 25 August 2017
Cited by 1 | PDF Full-text (12690 KB) | HTML Full-text | XML Full-text
Abstract
The aim of this investigation is the analysis of the opportunity introduced by the use of railway infrastructures for the power supply of fast charging stations located in highways. Actually, long highways are often located far from urban areas and electrical infrastructure, therefore
[...] Read more.
The aim of this investigation is the analysis of the opportunity introduced by the use of railway infrastructures for the power supply of fast charging stations located in highways. Actually, long highways are often located far from urban areas and electrical infrastructure, therefore the installations of high power charging areas can be difficult. Specifically, the aim of this investigation is the analysis of the opportunity introduced by the use of railway infrastructures for the power supply of fast charging stations located in highways. Specifically, this work concentrates on fast-charging electric cars in motorway service areas by using high-speed lines for supplying the required power. Economic, security, safety and environmental pressures are motivating and pushing countries around the globe to electrify transportation, which currently accounts for a significant amount, above 70 percent of total oil demand. Electric cars require fast-charging station networks to allowing owners to rapidly charge their batteries when they drive relatively long routes. In other words, this means about the infrastructure towards building charging stations in motorway service areas and addressing the problem of finding solutions for suitable electric power sources. A possible and promising solution is proposed in the study that involves using the high-speed railway line, because it allows not only powering a high load but also it can be located relatively near the motorway itself. This paper presents a detailed investigation on the modelling and simulation of a 2 × 25 kV system to feed the railway. A model has been developed and implemented using the SimPower systems tool in MATLAB/Simulink to simulate the railway itself. Then, the model has been applied to simulate the battery charger and the system as a whole in two successive steps. The results showed that the concept could work in a real situation. Nonetheless if more than twenty 100 kW charging bays are required in each direction or if the line topology is changed for whatever reason, it cannot be guaranteed that the railway system will be able to deliver the additional power that is necessary. Full article
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Open AccessArticle Real-Time Analysis of a Modified State Observer for Sensorless Induction Motor Drive Used in Electric Vehicle Applications
Energies 2017, 10(8), 1077; https://doi.org/10.3390/en10081077
Received: 5 May 2017 / Revised: 30 June 2017 / Accepted: 3 July 2017 / Published: 25 July 2017
Cited by 4 | PDF Full-text (9458 KB) | HTML Full-text | XML Full-text
Abstract
The purpose of this work is to present an adaptive sliding mode Luenberger state observer with improved disturbance rejection capability and better tracking performance under dynamic conditions. The sliding hyperplane is altered by incorporating the estimated disturbance torque with the stator currents. In
[...] Read more.
The purpose of this work is to present an adaptive sliding mode Luenberger state observer with improved disturbance rejection capability and better tracking performance under dynamic conditions. The sliding hyperplane is altered by incorporating the estimated disturbance torque with the stator currents. In addition, the effects of parameter detuning on the speed convergence are observed and compared with the conventional disturbance rejection mechanism. The entire drive system is first built in the Simulink environment. Then, the Simulink model is integrated with real-time (RT)-Lab blocksets and implemented in a relatively new real-time environment using OP4500 real-time simulator. Real-time simulation and testing platforms have succeeded offline simulation and testing tools due to their reduced development time. The real-time results validate the improvement in the proposed state observer and also correspond to the performance of the actual physical model. Full article
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Open AccessArticle Control Strategy for a Grid-Connected Inverter under Unbalanced Network Conditions—A Disturbance Observer-Based Decoupled Current Approach
Energies 2017, 10(7), 1067; https://doi.org/10.3390/en10071067
Received: 17 June 2017 / Revised: 3 July 2017 / Accepted: 10 July 2017 / Published: 22 July 2017
Cited by 6 | PDF Full-text (8653 KB) | HTML Full-text | XML Full-text
Abstract
This paper proposes a new approach on the novel current control strategy for grid-tied voltage-source inverters (VSIs) with circumstances of asymmetrical voltage conditions. A standard grid-connected inverter (GCI) allows the degree of freedom to integrate the renewable energy system to enhance the penetration
[...] Read more.
This paper proposes a new approach on the novel current control strategy for grid-tied voltage-source inverters (VSIs) with circumstances of asymmetrical voltage conditions. A standard grid-connected inverter (GCI) allows the degree of freedom to integrate the renewable energy system to enhance the penetration of total utility power. However, restrictive grid codes require that renewable sources connected to the grid must support stability of the grid under grid faults. Conventional synchronously rotating frame dq current controllers are insufficient under grid faults due to the low bandwidth of proportional-integral (PI) controllers. Hence, this work proposes a proportional current controller with a first-order low-pass filter disturbance observer (DOb). The proposed controller establishes independent control on positive, as well as negative, sequence current components under asymmetrical grid voltage conditions. The approach is independent of parametric component values, as it estimates nonlinear feed-forward terms with the low-pass filter DOb. A numerical simulation model of the overall power system was implemented in a MATLAB/Simulink (2014B, MathWorks, Natick, MA, USA). Further, particular results show that double-frequency active power oscillations are suppressed by injecting appropriate negative-sequence currents. Moreover, a set of simulation results provided in the article matches the developed theoretical background for its feasibility. Full article
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Open AccessArticle Power Balancing Control for Grid Energy Storage System in Photovoltaic Applications—Real Time Digital Simulation Implementation
Energies 2017, 10(7), 928; https://doi.org/10.3390/en10070928
Received: 19 May 2017 / Revised: 29 June 2017 / Accepted: 30 June 2017 / Published: 5 July 2017
Cited by 14 | PDF Full-text (3333 KB) | HTML Full-text | XML Full-text
Abstract
A grid energy storage system for photo voltaic (PV) applications contains three different power sources i.e., PV array, battery storage system and the grid. It is advisable to isolate these three different sources to ensure the equipment safety. The configuration proposed in this
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A grid energy storage system for photo voltaic (PV) applications contains three different power sources i.e., PV array, battery storage system and the grid. It is advisable to isolate these three different sources to ensure the equipment safety. The configuration proposed in this paper provides complete isolation between the three sources. A Power Balancing Control (PBC) method for this configuration is proposed to operate the system in three different modes of operation. Control of a dual active bridge (DAB)-based battery charger which provides a galvanic isolation between batteries and other sources is explained briefly. Various modes of operation of a grid energy storage system are also presented in this paper. Hardware-In-the-Loop (HIL) simulation is carried out to check the performance of the system and the PBC algorithm. A power circuit (comprised of the inverter, dual active bridge based battery charger, grid, PV cell, batteries, contactors, and switches) is simulated and the controller hardware and user interface panel are connected as HIL with the simulated power circuit through Real Time Digital Simulator (RTDS). HIL simulation results are presented to explain the control operation, steady-state performance in different modes of operation and the dynamic response of the system. Full article
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Open AccessFeature PaperArticle Grid Synchronization of a Seven-Phase Wind Electric Generator Using d-q PLL
Energies 2017, 10(7), 926; https://doi.org/10.3390/en10070926
Received: 10 May 2017 / Revised: 22 June 2017 / Accepted: 26 June 2017 / Published: 4 July 2017
Cited by 6 | PDF Full-text (13988 KB) | HTML Full-text | XML Full-text
Abstract
The evolving multiphase induction generators (MPIGs) with more than three phases are receiving prominence in high power generation systems. This paper aims at the development of a comprehensive model of the wind turbine driven seven-phase induction generator (7PIG) along with the necessary power
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The evolving multiphase induction generators (MPIGs) with more than three phases are receiving prominence in high power generation systems. This paper aims at the development of a comprehensive model of the wind turbine driven seven-phase induction generator (7PIG) along with the necessary power electronic converters and the controller for grid interface. The dynamic model of the system is developed in MATLAB/Simulink (R2015b, The MathWorks, Inc., Natick, MA, USA). A synchronous reference frame phase-locked loop (SRFPLL) system is incorporated for grid synchronization. The modeling aspects are detailed and the system response is observed for various wind velocities. The effectiveness of the seven phase induction generator is demonstrated with the fault tolerant capability and high output power with reduced phase current when compared to the conventional 3-phase wind generation scheme. The response of the PLL is analysed and the results are presented. Full article
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Review

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Open AccessEditor’s ChoiceReview A Comprehensive Study of Key Electric Vehicle (EV) Components, Technologies, Challenges, Impacts, and Future Direction of Development
Energies 2017, 10(8), 1217; https://doi.org/10.3390/en10081217
Received: 8 May 2017 / Revised: 21 July 2017 / Accepted: 21 July 2017 / Published: 17 August 2017
Cited by 24 | PDF Full-text (28972 KB) | HTML Full-text | XML Full-text
Abstract
Electric vehicles (EV), including Battery Electric Vehicle (BEV), Hybrid Electric Vehicle (HEV), Plug-in Hybrid Electric Vehicle (PHEV), Fuel Cell Electric Vehicle (FCEV), are becoming more commonplace in the transportation sector in recent times. As the present trend suggests, this mode of transport is
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Electric vehicles (EV), including Battery Electric Vehicle (BEV), Hybrid Electric Vehicle (HEV), Plug-in Hybrid Electric Vehicle (PHEV), Fuel Cell Electric Vehicle (FCEV), are becoming more commonplace in the transportation sector in recent times. As the present trend suggests, this mode of transport is likely to replace internal combustion engine (ICE) vehicles in the near future. Each of the main EV components has a number of technologies that are currently in use or can become prominent in the future. EVs can cause significant impacts on the environment, power system, and other related sectors. The present power system could face huge instabilities with enough EV penetration, but with proper management and coordination, EVs can be turned into a major contributor to the successful implementation of the smart grid concept. There are possibilities of immense environmental benefits as well, as the EVs can extensively reduce the greenhouse gas emissions produced by the transportation sector. However, there are some major obstacles for EVs to overcome before totally replacing ICE vehicles. This paper is focused on reviewing all the useful data available on EV configurations, battery energy sources, electrical machines, charging techniques, optimization techniques, impacts, trends, and possible directions of future developments. Its objective is to provide an overall picture of the current EV technology and ways of future development to assist in future researches in this sector. Full article
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