New opportunities and perspectives for the electric vehicle operation in smart grids and smart homes scenarios

New perspectives for the electric vehicle (EV) operation in smart grids and smart homes context are presented. Nowadays, plugged-in EVs are equipped with on-board battery chargers just to perform the charging process from the electrical power grid (G2V – grid-to-vehicle mode). Although this is the main goal of such battery chargers, maintaining the main hardware structure and changing the digital control algorithm, the on-board battery chargers can also be used to perform additional operation modes. Such operation modes are related with returning energy from the batteries to the power grid (V2G- vehicle-to-grid mode), constraints of the electrical installation where the EV is plugged-in (iG2V – improved grid-tovehicle mode), interface of renewables, and contributions to improve the power quality in the electrical installation. Besides the contributions of the EV to reduce oil consumption and greenhouse gas emissions associated to the transportation sector, through these additional operation modes, the EV also represents an important contribution for the smart grids and smart homes paradigms. Experimental results introducing the EV through the aforementioned interfaces and operation modes are presented. An on-board EV battery charger prototype was used connected to the power grid for a maximum power of 3.6 kW.This work has been supported by COMPETE: POCI-01-0145-FEDER-007043 and FCT – Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/2013. This work is financed by the ERDF – European Regional Development Fund through the Operational Programme for Competitiveness and Internationalisation Ǧ COMPETE 2020 Programme, and by National Funds through the Portuguese funding agency, FCT - Fundação para a Ciência e a Tecnologia, within project SAICTPAC/0004/2015- POCI- 01-0145-FEDER-016434.info:eu-repo/semantics/publishedVersio

Operation modes for the electric vehicle in smart grids and smart homes: present and proposed modes

This paper presents the main operation modes for an electric vehicle (EV) battery charger framed in smart grids and smart homes, i.e., are discussed the present-day and are proposed new operation modes that can represent an asset towards EV adoption. Besides the well-known grid to vehicle (G2V) and vehicle to grid (V2G), this paper proposes two new operation modes: Home-to-vehicle (H2V), where the EV battery charger current is controlled according to the current consumption of the electrical appliances of the home (this operation mode is combined with the G2V and V2G); Vehicle-for-grid (V4G), where the EV battery charger is used for compensating current harmonics or reactive power, simultaneously with the G2V and V2G operation modes. The vehicle-to-home (V2H) operation mode, where the EV can operate as a power source in isolated systems or as an off-line uninterruptible power supply to feed priority appliances of the home during power outages of the electrical grid is presented in this paper framed with the other operation modes. These five operation modes were validated through experimental results using a developed 3.6 kW bidirectional EV battery charger prototype, which was specially designed for these operation modes. The paper describes the developed EV battery charger prototype, detailing the power theory and the voltage and current control strategies used in the control system. The paper presents experimental results for the various operation modes, both in steady-state and during transients

E-Mobility -- Advancements and Challenges

Mobile platforms cover a broad range of applications from small portable electric devices, drones, and robots to electric transportation, which influence the quality of modern life. The end-to-end energy systems of these platforms are moving toward more electrification. Despite their wide range of power ratings and diverse applications, the electrification of these systems shares several technical requirements. Electrified mobile energy systems have minimal or no access to the power grid, and thus, to achieve long operating time, ultrafast charging or charging during motion as well as advanced battery technologies are needed. Mobile platforms are space-, shape-, and weight-constrained, and therefore, their onboard energy technologies such as the power electronic converters and magnetic components must be compact and lightweight. These systems should also demonstrate improved efficiency and cost-effectiveness compared to traditional designs. This paper discusses some technical challenges that the industry currently faces moving toward more electrification of energy conversion systems in mobile platforms, herein referred to as E-Mobility, and reviews the recent advancements reported in literature

Secondary-Side Control in Dynamic Wireless Power Transfer Systems for Double-Sided Inductor-Capacitor-Capacitor and Series-Series Compensation Topologies

Electric Vehicles (EVs) are fast becoming a great alternative as future mode of transportation, due to their promise of low emissions. Nevertheless, EVs suffer from battery related problems such as large size, heavy weight, high price, long charging times and a short driving range. Dynamic wireless power transfer systems (DWPTSs) address the battery issue by providing power to the vehicle while in motion, and eliminate the need of plugging. However, unavoidable load and coupling coefficient variations cause degradation of power delivery and efficiency. Hence, a controller must be added to the dynamic charger for power conditioning and efficiency enhancement. This project is focused on the control stage of the DWPTS adopting a post-regulation scheme as control strategy. It proposes the integration of a secondary-side-only control under double-sided inductor-capacitor-capacitor (LCC) and series-series compensation topologies. A synchronous buck converter is used to step down the voltage to the maximum power transfer efficiency (MPTE) conditions and control the direct current (DC) link by adjusting the duty cycle of the control pulse. Averaged alternating current (AC) modelling is applied for designing the controller to smooth and speed the response of both systems. An estimation equation for coupling coefficient and a controller for the double-sided LCC compensation topology are introduced. A comparison study between these two topologies comprised of their characteristics and response to the controller is carried out

Uncertainty Quantification for SAE J2954 Compliant Static Wireless Charge Components

The present work aims at quantifying how, and how much, the uncertainties on the components and material parameters of a wireless power transfer (WPT) system for the static charge of electric vehicles affect the overall efficiency and functionality of the final produced device. With the aim of considering the perspective of a possible industrial developer, the parameters selected for the uncertainty quantification are chosen to be the capacitance values of the compensation capacitors and the electromagnetic material parameters used for the construction of the magnetic structure of a WPT system, i.e. the parameters of the elements to be purchased. The analysis is based on a standard system among the ones provided by the current SAE J2954 recommended practice

Isolated Wired and Wireless Battery Charger with Integrated Boost Converter for PHEV and EV Applications

Vehicle charging and vehicle traction drive components can be integrated for multi-functional operations, as these functions are currently operating independently. While the vehicle is parked, the hardware that is available from the traction drive can be used for charging. The only exception to this would be the dynamic vehicle-charging concept on roadways. WPT can be viewed as a revolutionary step in PEV charging because it fits the paradigm of vehicle to infrastructure (V2I) wirelessly. WPT charging is convenient and flexible not only because it has no cables and connectors that are necessary, but due more to the fact that charging becomes fully independent. This is possibly the most convenient attribute of WPT as PEV charging can be fully autonomous and may eventually eclipse conductive charging. This technology also provides an opportunity to develop an integrated charger technology that will allow for both wired and wireless charging methods. Also the integrated approach allows for higher charging power while reducing the weight and volume of the charger components in the vehicle. The main objective of this work is to design, develop, and demonstrate integrated wired and wireless chargers with boost functionality for traction drive to provide flexibility to the EV customers

Wireless Power Transfer Technology for Electric Vehicle Charging

In the years 1884-1889, after Nicola Tesla invented "Tesla Coil", wireless power transfer (WPT) technology is in front of the world. WPT technologies can be categorized into three groups: inductive based WPT, magnetic resonate coupling (MRC) based WPT and electromagnetic radiation based WPT. MRC-WPT is advantageous with respect to its high safety and long transmission distance. Thus it plays an important role in the design of wireless electric vehicle (EV) charging systems. The most significant drawback of all WPT systems is the low efficiency of the energy transferred. Most losses happen during the transfer from coil to coil. This thesis proposes a novel coil design and adaptive hardware to improve power transfer efficiency (PTE) in magnetic resonant coupling WPT and mitigate coil misalignment, a crucial roadblock to the acceptance of WPT for EV. In addition, I do some analysis of multiple segmented transmitters design for dynamic wireless EVs charging and propose an adaptive renewable (wind) energy-powered dynamic wireless charging system for EV

Modeling of Magnetic Resonance Wireless Electric Vehicle Charging

Due to the fast-growing market for an electric vehicle, it is necessary that the drawbacks involved in electric vehicle technology should be overcome, therefore introducing a wireless charging technique which is more convenient as battery cost, recharge time and weight has been removed. Different wireless charging techniques for electric vehicles are discussed. This research work investigates the feasibility of wireless power transfer for Electric Vehicles by electromagnetic resonance coupling. Wireless power transfer (WPT) for Electric Vehicles by magnetic resonance coupling is of high priority due to its efficiency, high power transmission, and more considerable charging distance. Simulation results show the energy transfer efficiency between two magnetically coupled resonating coils. However, results show the effects of parameters such as an inductor, capacitor, load and coupling coefficient on efficiency. Additionally, implementation of a closed loop circuit using a three-level cascaded PI controller for the dynamic wireless electric vehicle charging to eliminate the variation of voltage because of varied spacing existing between both coils as the vehicle is in motion and thereby delivering a constant voltage and constant current to the load is carried out. Simulation results and comparison with a single level PI controller indicate the effectiveness of the control method. A fuzzy logic and neuro-fuzzy controller are implemented for the wireless electric vehicle transfer which is seen to be more robust than the PI controller as there is no undershoot in the output voltage. Furthermore, wireless power transfer with three - level cascaded PI controller with MPPT is designed. The proposed system consists of a solar PV array, boost DC/DC converter, inverter, transmitter coil, a receiver coil, rectifier, buck converter, and batteries. The design of the MPPT controller tracks the highest voltage and current from the PV array required to charge a battery in which the highest power point voltage is 61.5 V. The stability analysis for the closed-loop system has been done and the system is asymptotically stable

Optimal Speed Control of Electric Vehicles in Traffic with Wireless Charging

With the increase in electric vehicle use in recent years and expected increase in the future, a wireless network provides a possible option to allow vehicles with a route while maintaining an approximate net-zero energy balance under certain scenarios. In this type of network, a collection of wireless charging pads is installed under the road, and energy transfer occurs, while a vehicle with wireless charging capability is driven over the charging pads. This thesis describes a methodology and modeling to solve an optimization problem involving a speed-controlled vehicle in traffic. The methodology incorporates a receding horizon dynamic model with constraints. Suboptimal results are described under multiple traffic scenarios. Several scenarios are explored while the vehicle under constrain (controlled vehicle) is dynamic, its charging behavior with being the only vehicle on the route and while the vehicle is following the route while other vehicles present on the route and the controlled vehicle is following the traffic. Besides, describe the methodology for dynamic charging and the optimal charge station for the current charging rate. This model of predictive control can be adopted in real-time given certain information is available for the controlled vehicle and traffic conditions