Today, there are many recent developments that focus on improving the electric vehicles and their components, particularly regarding advances in batteries, energy management systems, autonomous features and charging infrastructure This plays an important role in developing next electric vehicle generations, and encourages more efficient and sustainable eco-system This paper not only provides insights in the latest knowledge and developments of electric vehicles (EVs), but also the new promising and novel EV technologies based on scientific facts and figures—which could be from a technological point of view feasible by 2030 In this paper, potential design and modelling tools, such as digital twin with connected Internet-of-Things (IoT), are addressed Furthermore, the potential technological challenges and research gaps in all EV aspects from hard-core battery material sciences, power electronics and powertrain engineering up to environmental assessments and market considerations are addressed The paper is based on the knowledge of the 140+ FTE counting multidisciplinary research centre MOBI-VUB, that has a 40-year track record in the field of electric vehicles and e-mobility

https://www.mdpi.com/2032-6653/12/1/20/pdf

Beyond the State of the Art of Electric Vehicles: A Fact-Based Paper of the Current and Prospective Electric Vehicle Technologies

The transportation sector accounts for a significant share of greenhouse gas emissions. Hence, the electrification of this sector is a crucial contributor to the mitigation of global warming. Recent studies suggest that electric vehicles will be economically paired with internal combustion engine vehicles in the near future. However, relying on private vehicle decarbonization only cannot deliver comprehensive space management efficiency solutions in urban environments. Therefore, it is essential to invest in the technological development and deployment of electric buses for public transportation, directly enhancing the quality of life in large cities. From this perspective, this review examines a wide range of scientific literature on electric bus research using science mapping methods and content analysis to support critical thinking unveiling the main research streams, methods, and gaps of the field. The analysis indicates that future research on electric buses will be mainly devoted to sustainability (encompassing economic, environmental and quality of service dimensions), energy management strategies, and fleet operation. • Electric bus research is assessed using science mapping and content analysis. • The main electric bus research streams are recognized. • Content analysis of relevant articles is carried out to assess the methods used. • Future research is mainly aimed at energy management strategy and fleet operation. • Recent research gaps are identified. 

A review of electric bus vehicles research topics – Methods and trends

This paper proposes a co-design optimization procedure of a high-power off-board charger for electric vehicle (EV) applications. The primary purpose is to design a 175 kW SiC DC-charging system with high power density to achieve high efficiency at a wide operating range. For the active part of the DC off-board charger, a three-phase active front end (AFE) rectifier topology is considered in the design optimization and the modelling. The design methodology focuses on the optimal design of the passive filters, accurate electro-thermal modelling of the converter, inductor design, capacitor selection, loss and geometric modelling of the passive filters and control system design. The design optimization of the high-power charging system is performed in MATLAB Simulink using a closed-loop dynamic electro-thermal simulation of the off-board charger. The switching frequency, loss and temperature-dependent efficiency of the charger is investigated in parallel. Through this proposed technique, efficiency greater than 96% is achieved at a switching frequency of 40 kHz, along with a smaller size and lower weight of the system. Moreover, it operates with a current total harmonic distortion (THDi) below 3% and a power factor (PF) above 99% at rated power condition.

/pdf/design-optimization-and-electro-thermal-modeling-of-an-off-3tkjtsbtgr.pdf

Design Optimization and Electro-Thermal Modeling of an Off-Board Charging System for Electric Bus Applications

This paper provides a comprehensive overview of the state-of-the-art related to the implementation of battery electric buses (BEBs) in cities. In recent years, bus operators have started focusing on the electrification of their fleet to reduce the air pollutants in cities, which has led to a growing interest from the scientific community. This paper presents an analysis of the BEB powertrain topology and the charging technology of BEBs, with a particular emphasis on the power electronics systems. Moreover, the different key technical requirements to facilitate the operation of BEBs are addressed. Accordingly, an in-depth review on vehicle scheduling, charger location optimization and charging management strategies is carried out. The main findings concerning these research fields are summarized and discussed. Furthermore, potential challenges and required further developments are determined. Based on this analysis, it can be concluded that an accurate energy consumption assessment of their BEBs is a must for bus operators, that real-time, multi-objective smart charging management strategies with V2X features should be included when performing large bus fleet scheduling and that synchronized opportunity charging, smart green depot charging, and electric bus rapid transit can further reduce the impact on the grid. This review paper should help to enable a smarter and more efficient integration of BEBs in cities in the future.

Smart Integration of Electric Buses in Cities: A Technological Review

The emphasis on clean and green technologies to curtail greenhouse gas emissions due to fossil fuel-based economies has originated the shift towards electric mobility. As on-road electric vehicles (EVs) have shown exponential growth over the last decade, so have the charging demands. The provision of charging facilities from the low-voltage network will not only increase the distribution system’s complexity and dynamics but will also challenge its operational capabilities, and large-scale upgrades will be required to meet the inevitably increasing charging demands. An ultra-fast (UF) charging infrastructure that replicates the gasoline refueling network is urgently needed to facilitate a seamless transition to EVs and ensure smooth operation. This paper presents a review of state-of-the-art DC fast chargers, the charging infrastructure’s current status, motivation, and challenges for medium-voltage (MV) UF charging stations (UFCS). Furthermore, we consider the possible UFCS architectures and suitable power electronics topologies for UF charging applications. To address the peak formation issues in the daily load profile and high operational expenses of UFCSs, integration of renewable energy sources and energy storage systems due to their technological and economic benefits is being considered. The benefits of line frequency transformer (LFT) replacement with a solid-state transformer (SST), SST models, SST-based UF chargers, and MV SST-based UFCS architectures, as well as related MV active front-end and back-end power electronics topologies, are presented. Finally, the application of microgrids’ hierarchical control architecture is considered for chargers and system-level control and management of UFCSs.

https://ieeexplore.ieee.org/ielx7/8782706/8955964/09786788.pdf

An Overview on Medium Voltage Grid Integration of Ultra-Fast Charging Stations: Current Status and Future Trends

This paper proposes an optimal design procedure of high-power off-board charger (Off-BC) systems for electric vehicle EV applications. The main purpose is to design a high-power DC charging system with low current ripples for achieving maximum efficiency. This paper presents linear and non-linear modelling of a 175kW three-phase AC/DC converter for EV applications. This paper also presents manufacturer’s datasheet driven accurate electro-thermal modelling. The design methodology is categorized into analytical modelling of three-phase active rectifier, optimal design strategy of passive filters, and control design of DC bus voltage. Finally, closed-loop dynamic electro-thermal behavior of Off-BC is simulated using MATLAB Simulink®. The proposed Off-BC operates with a current Total Harmonic Distortion (THD) below 3% and Power Factor (PF) above 99%, while the highest efficiency achieved is approximately 99% at rated power condition.

Optimal Design Strategy and Electro-Thermal Modelling of a High-Power Off-Board Charger for Electric Vehicle Applications

This paper proposes an analytical and dynamic electro-thermal model of a three-phase inverter based on wide bandgap semiconductors (SiC) for application in electric vehicles (EV). The optimal design approach of the passive filters is presented for LCL filters at DC side and LC filters at AC side of the inverter. The analytical modelling is performed, which includes mathematical representation of the inverter’s power losses based on the specifications of the datasheet of the power modules. The dynamic electro-thermal simulation model of the inverter with integrated power loss model is developed. The designed state-space system thermal model is incorporated and can be used as a virtual sensor, for the conversion of power losses to temperature. With this inverter model, it’s possible to simulate designs for achieving high efficiency in a specific operating range of temperature, with high specific power and reduced cost and size. The proposed design is considered for a power load of 20kW.

A Rapid Non-Linear Computation Model of Power Loss and Electro Thermal Behaviour of Three-Phase Inverters in EV Drivetrains

This paper proposes a masterless control strategy for parallel active front-end (AFE) systems for off-board electric vehicle (EV) charging and stationary applications. The proposed solution enables high modularity in AC-DC power converters designated for EV charger systems, where the AFE modules can be separated and recombined, enabling them to be more versatile, flexible and scalable. The presented AFE rectifier system consists of several self-sufficient modules with distributed control that can exchange data through CAN bus. The proposed system has functions like dynamic resource allocation, automatic interleaving, circulating current control, accurate current sharing and demonstrates increased fault tolerance. In this paper, the main operating principle of the masterless control of modular AFE rectifier systems is explained. Moreover, the performance of the AFE rectifier system supplying power to a 100 kW off-board DC charger is demonstrated by MATLAB Simulink with changing load, module failures and possible manufacturing flaws.

Haaris Rasool

Papers

Design Optimization and Electro-Thermal Modeling of an Off-Board Charging System for Electric Bus Applications

Smart Integration of Electric Buses in Cities: A Technological Review

Optimal Design Strategy and Electro-Thermal Modelling of a High-Power Off-Board Charger for Electric Vehicle Applications

A Rapid Non-Linear Computation Model of Power Loss and Electro Thermal Behaviour of Three-Phase Inverters in EV Drivetrains

Masterless Control of Parallel Modular Active front-end (AFE) Systems for Vehicles and Stationary Applications