A Review of Current Research Trends in Power-Electronic Innovations in Cyber-Physical Systems.

In this paper, a broad overview of the current research trends in power-electronic innovations in cyber-physical systems (CPSs) is presented. The recent advances in semiconductor device technologies, control architectures, and communication methodologies have enabled researchers to develop integrated smart CPSs that can cater to the emerging requirements of smart grids, renewable energy, electric vehicles, trains, ships, internet of things (IoTs), etc. The topics presented in this paper include novel power-distribution architectures, protection techniques considering large renewable integration in smart grids, wireless charging in electric vehicles, simultaneous power and information transmission, multi-hop network-based coordination, power technologies for renewable energy and smart transformer, CPS reliability, transactive smart railway grid, and real-time simulation of shipboard power systems. It is anticipated that the research trends presented in this paper will provide a timely and useful overview to the power-electronics researchers with broad applications in CPSs.post-print2.019 K

Modeling And Analysis Of The Eds Maglev System With The Halbach Magnet Array

The magnetic field analysis based on the wavelet transform is performed. The Halbach array magnetic field analysis has been studied using many methods such as magnetic scalar potential, magnetic vector potential, Fourier analysis and Finite Element Methods. But these analyses cannot identify a transient oscillation at the beginning stage of levitation. The wavelet transform is used for analyzing the transient oscillatory response of an EDS Maglev system. The proposed scheme explains the under-damped dynamics that results from the cradle\u27s dynamic response to the irregular distribution of the magnetic field. It suggests this EDS Maglev system that responds to a vertical repulsive force could be subject to such instability at the beginning stage of a low levitation height. The proposed method is useful in analyzing instabilities at the beginning stage of levitation height. A controller for the EDS maglev system with the Halbach array magnet is designed for the beginning stage of levitation and after reaching the defined levitation height. To design a controller for the EDS system, two different stages are suggested. Before the object reaches a stable position and after it has reached a stable position. A stable position can be referred to as a nominal height. The former is the stage I and the latter is the stage II. At the stage I, to achieve a nominal height the robust controller is investigated. At the stage II, both translational and rotational motions are considered for the control design. To maintain system stability, damping control as well as LQR control are performed. The proposed method is helpful to understand system dynamics and achieve system stability

Controlling Techniques for STATCOM using Artificial Intelligence

The static synchronous compensator (STATCOM) is a power electronic converter designed to be shunt-connected with the grid to compensate for reactive power. Although they were originally proposed to increase the stability margin and transmission capability of electrical power systems, there are many papers where these compensators are connected to distribution networks for voltage control and power factor compensation. In these applications, they are commonly called distribution static synchronous compensator (DSTATCOM). In this paper we have focussed on STATCOM and the controlling techniques which are based on artificial intelligence

Fault Management in DC Microgrids:A Review of Challenges, Countermeasures, and Future Research Trends

The significant benefits of DC microgrids have instigated extensive efforts to be an alternative network as compared to conventional AC power networks. Although their deployment is ever-growing, multiple challenges still occurred for the protection of DC microgrids to efficiently design, control, and operate the system for the islanded mode and grid-tied mode. Therefore, there are extensive research activities underway to tackle these issues. The challenge arises from the sudden exponential increase in DC fault current, which must be extinguished in the absence of the naturally occurring zero crossings, potentially leading to sustained arcs. This paper presents cut-age and state-of-the-art issues concerning the fault management of DC microgrids. It provides an account of research in areas related to fault management of DC microgrids, including fault detection, location, identification, isolation, and reconfiguration. In each area, a comprehensive review has been carried out to identify the fault management of DC microgrids. Finally, future trends and challenges regarding fault management in DC-microgrids are also discussed

A comprehensive study of key Electric Vehicle (EV) components, technologies, challenges, impacts, and future direction of development

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 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

Real-time Energy Management System of Battery-Supercapacitor in Electric vehicles

This thesis presents the design, simulation and experimental validation of an Energy Management System (EMS) for a Hybrid Energy Storage System (HESS) composed of lithium ion batteries and Supercapacitors (SCs) in electric vehicles. The aim of the EMS is to split the power demand considering the weaknesses and strengths or the power sources. The HESS requires an EMS to determine power missions for the battery and SC in real time, where the SC is commanded to assist the battery during high power demand and recover the energy generated during braking. Frequency sharing techniques have been proposed by researchers to achieve this objective, including the Discrete Wavelet Transform (DWT) and conventional filtration methods (low and high pass filters). However, filtration approaches can introduce delay (milliseconds to tens of seconds) in the frequency components which undermines the hybridisation advantages. Hence, the selection of the filtration technique and filter design are crucial to the system's performance. Researchers have proposed power demand prediction methodologies to deal with time delay, however, the advantages and drawbacks of using such methods have not been investigated thoroughly, particularly whether time delay compensation and its inherent prediction error improves the system performance, efficiency, and timely SC contribution during the motoring and braking stages. This work presents a fresh perspective to this research field by introducing a novel approach that deals with delay without complicated prediction algorithms and improves the SC contribution during the motoring and braking stages while reducing energy losses in the system. The proposed EMS allows the SC to provide timely assistance during motoring and to recover the braking energy generated. A charging strategy controls energy circulation between the battery and SC to keep the SC charge availability during the whole battery discharge cycle. The performance and efficiency of the HESS is improved when compared to the traditional use of conventional filtration techniques and the DWT. Results show that the proposed EMS method improves the energy efficiency of the HESS. For the US06 driving cycle, the energy efficiency is 91.6%. This is superior to the efficiency obtained with an EMS based on a high pass filter (41.3%), an EMS based on DWT high frequency component (30.3%) and an EMS based on the predicted DWT high frequency component (41%)

Advanced Signal Processing Techniques Applied to Power Systems Control and Analysis

The work published in this book is related to the application of advanced signal processing in smart grids, including power quality, data management, stability and economic management in presence of renewable energy sources, energy storage systems, and electric vehicles. The distinct architecture of smart grids has prompted investigations into the use of advanced algorithms combined with signal processing methods to provide optimal results. The presented applications are focused on data management with cloud computing, power quality assessment, photovoltaic power plant control, and electrical vehicle charge stations, all supported by modern AI-based optimization methods

Investigation to Improve the Control and Operation of a Three-phase Photovoltaic Grid-tie Inverter

Solar Energy or more precisely photovoltaic energy is one of the most promising sources of electricity for the future and it can be used as a distributed generator (DG) to play its role in ‘smart grids of the future’. Distributed PV (photovoltaic) generators can provide numerous potential benefits such as augmenting the capacity of distribution systems, deferring capital investments on distribution and transmission (T&D) systems and improving power quality and system reliability. The PV energy which possesses very special I-V and P-V characteristics has to be conditioned by a PV inverter before it can be consumed by an ac load and/or the grid. Technical improvements in maximum power point tracking (MPPT) and islanding detection are proposed for a three-phase photovoltaic grid tied inverter (GTI) keeping in mind the requirements of the international standards for connecting a DG to the utility grid. This PhD thesis will contain four major sections which are briefed below. A three phase GTI has been simulated using Matlab/Simulink to test the various control blocks and algorithms involved in the building of the power conditioning unit. A DS1104 dSpace DSP controlled, 5.625 kW three-phase GTI laboratory prototype has then been built. Various hardware components, including inverter switches, gate drivers, LCL filter, rectified dc source, boost circuit, transformer, 16A current protection circuit, additional sensing interface circuits and PWM level shifter have been designed and built within the laboratory. The software algorithm created in Simulink communicates directly with the built hardware via the graphical user interface that has been designed with dSPace Control Desk. Algorithms have been developed for the inverter in order to protect it from operating out of nominal frequency and voltage ranges. An algorithm has been developed iii to ensure the boost dc link voltage is controlled to 300V when dc voltage source varies between 150V and 265V. The Z-Source inverter (ZSI), with nine operating states that employs an extra shoot through (ST) state compared to the eight states (6 active and 2 zero states) in traditional VSI is one of the most recent boost topologies that has been proposed in the literature. A step by step design procedure of a ZSI has been developed. A topology comparison between Z-Source inverter and dc-dc boost with VSI is done using literature and simulations. Merits and demerits of the two topologies are summarised and the choice of the topology is justified. MPPT is a process by which maximum power from a PV panel or array is tracked and absorbed during a particular weather condition (insolation level and temperature). There are various MPPT techniques in the literature which are reviewed and a new MPPT approach based on the P&O (Perturb and Observe) method is proposed. The proposed technique is tested on the three phase GTI simulation, it is analysed and compared to the conventionally reviewed P&O MPPT approach. The issue of islanding of GTI’s has raised concerns of equipment and personal safety, for which reason the inverter has to detect and stop the inverter during loss of grid. Passive techniques can detect the grid failure quite well when there is a large power mismatch between the DG and the load but not when the mismatch is small. Active techniques can work well with lower levels of power mismatch but they degrade power quality by introducing disturbances into the power system. A novel wavelet based antiislanding technique is proposed and incorporated into the running hardware protection. This uses physical measurements to reduce the non-detection zone close to zero and keep the power quality of the inverter output unchanged. The developed algorithms have been validated in the laboratory prototype and yield very satisfactory performance