Power Transfer For Electric Vehicles Research Articles

Wireless Power Transfer for Electric Vehicle Using an Adaptive Robot

Charging time and power transfer efficiency are the main challenges of wireless power transfer for electric vehicles. It is proposed in this paper to resolve both issues using the transformer induction concept as well as adaptive robotic technology. To this end, an autonomous robotic arm equipped with several sensors is mounted to the vehicle's undercarriage that carries a receiving coil. In case that the vehicle is parked in a parking spot equipped with wireless power transmitters, the robot will locate the receiving coil on the right place that is above the transmitting core when the vehicle is parked. When the vehicle is driven on a road equipped with the wireless power transmission system, the proposed mechanism provides the driver with signals that indicate the most efficient driving trajectory. To achieve the maximum efficiency, an advanced mathematical adaptive algorithm based on the extremum seeking method is employed. In addition, silicon carbide metal-oxide semiconductor field-effect transistor is used in power converter to retain the frequency as high as possible to decrease the charging time. Through this method, the above issues and the problem of large non-permeable air gap and accordingly electromagnetic interference are resolved; while, the charging time is decreased dramatically.

Characteristic comparison of different resonators to extend transfer distance in superconducting wireless power transfer for electric vehicle using high temperature superconducting resonance coil

AbstractThis paper presents the feasibility of technical fusion between wireless power transfer (WPT) based on resonance coupling system and superconducting technology to improve the transfer efficiency and spread the electromagnetic field widely in spite of small size coils. Until now, the various copper wires have generally been adopted in WPT system. From this reason, the transfer efficiency is limited since the copper wire keeps low Q intrinsically. On the other hand, as superconducting wires keep larger current density and higher Q value, the superconducting resonance coil can be expected as a reasonable option to deliver large transfer power as well as improve the transfer ratio since it exchanges energy at a much higher rate and keeps stronger magnetic fields out. In this study, we examined the transmission ratio using HTS and cooper wires in the antenna (Tx) or/and receiver (Rx) within input power of 500 W under various performances; copper Tx to copper Rx, HTS Tx to copper Rx, copper Tx to HTS Rx...

Wireless power transfer for electric vehicle at the kilohertz band

Wireless power transfer (WPT) technology has attracted considerable attention in recent years, and there have been numerous reports about this technology. This has led to ambiguity over the actual state of WPT technology for electrical vehicles (EV) in Japan. Therefore, this paper describes the WPT technology using the kilohertz band for EVs available in Japan. WPT requirement for EV, circuit topology, coil types, control method, component, foreign object detection, and dynamic charging in Japan are summarized in this study. © 2016 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Gaussian process surrogate model for the design of circular, planar coils used in inductive power transfer for electric vehicles

In recent years, there has been an increased interest in inductive charging systems for electric vehicles. Since the efficiency of the charging system is highly dependent on the couplers used, the design of the coil system is a key issue for inductive power transfer (IPT). As the coil system has numerous variables, a full factorial analysis of the system is not possible due to the long computation time of the numerical simulation model. Therefore, a surrogate model is developed, which approximates and interpolates the complex and expensive simulation code. With this ‘model of the model’, a reliable and efficient dimensioning and optimisation of the coil system within seconds is possible. It identifies the main important factors and their influence on the IPT system. Based on this surrogate model, important factor relations can be determined, which allow a significant improvement of the behaviour of the IPT system. All simulations conducted in this study are validated and verified.

DynamicWireless Power Transfer System for Electric Vehicles to Simplify Ground Facilities - Real-time Power Control and Efficiency Maximization -

This paper focuses on dynamic wireless power transfer for electric vehicles and proposes a vehicle-side control method for real-time power control and efficiency maximization. The proposed control strategy and controller design are presented based on a real-time estimation of the mutual inductance between a transmitter and a receiver. Simulations and experiments demonstrate that the proposed method can achieve the maximum efficiency and the desired power simultaneously.

Design Considerations of Superconducting Wireless Power Transfer for Electric Vehicle at Different Inserted Resonators

The wireless power transfer (WPT) technology based on strongly resonance coupled method realizes large power charging without any wires through the air. Recently, the WPT systems have started to be applied to the wireless charging for electrical vehicles (EVs) because of their advantages compared with the wired counterparts, such as convenient, safety, and fearless transmission of power. However, there are challenges in its commercialization, such as delivery distance and efficiency. To solve the problems, we proposed the technical fusion using high-temperature superconducting (HTS) resonance coil in the WPT system, which is called superconducting wireless power transfer for electric vehicle (SUWPT4EV) system. Since the superconducting wire has merits, i.e., a larger current density and a higher Q value than normal conducting wire, the HTS antenna coil enables to deliver a mass amount of electric energy in spite of a small-scale antenna, as well as is possible to keep much stronger magnetic fields out in the peripheral regions. Thus, the SUWPT4EV system has been expected as a reasonable option to improve the transfer efficiency of large electric power. In this study, as an advanced approach, we proposed the advanced SUWPT4EV system with inserted resonator using noncooled copper, cooled copper, and HTS resonators, respectively, in order to expand the transfer distance and improve the transfer ratio. In this paper, we presented operating characteristics of the advanced SUWPT4EV system and achieved the improvement and effects of transmission power for inserted resonators within 40-cm distance under radio frequency power of 370 kHz below 600 W.

A REVIEW ON WIRELESS POWER TRANSFER (WPT) FOR ELECTRIC VEHICLE (EV) APPLICATIONS

A REVIEW ON WIRELESS POWER TRANSFER (WPT) FOR ELECTRIC VEHICLE (EV) APPLICATIONS

Wireless Power Transfer for Electric Vehicles

Electric vehicle (EV) technology has the potential to help reduce CO2 emissions and harmful air pollution in urban areas. However, the current performance of the battery technology and plug-in charging infrastructure limit the extent to which the EV technology can be introduced and transport applications in which it can be utilised. Wireless power transfer technology could be used to develop a network of charging points and road sections capable of supplying power wirelessly to EVs that allow opportunistic charging of EVs to overcome the issues of limited range and long charging times. This article describes the principles behind the technology and discusses its possible applications in transport, opportunities that it may provide, and current issues and challenges to adoption. Case studies and examples of activities around the world where this technology is being developed, trialled or implemented are provided to support the discussion.

CONTACTLESS ELECTRIC VEHICLE CHARGING USING MAGNETIC RESONANCE COUPLING METHOD.

A convenient charging mechanism will be of great help in dispersal of Electric Vehicles more widely. The concept of Wireless transfer of electrical energy will make this possible. The feasibility of wireless power transfer for Electric Vehicles by electromagnetic resonance coupling is investigated in this paper. Using electromagnetic resonance coupling, large amount of power can be transmitted over large air gaps. The experiment is carried out on small sized antennas that can be equipped at the bottom of a vehicle. The efficiency characteristics of power transmitted wirelessly are analyzed by varying - frequency of power, gap between receiving and transmitting coils and power to be transmitted. Power transmission efficiencies at resonant frequencies are investigated. Wireless charging mechanism will make Electric Vehicles more user friendly and also reduce Carbon emissions. The feasibility of wireless power transfer with large air gaps and high efficiency by small sized antennas is proposed and analyzed in this paper.

Operating characteristics of contactless power transfer for electric vehicle from HTS antenna to normal conducting receiver

As contactless power transfer (CPT) technology using strongly coupled electromagnetic resonators is a recently explored technique to realize the large power delivery and storage without any cable or wire, this technique is required for diffusion of electric vehicles (EVs) since it makes possible a convenient charging system. Typically, since the normal conducting coils are used as a transmitting coil in the CPT system, there is limited to deliver the large power promptly. From this reason, we proposed the combination CPT technology with HTS transmitting antenna, it is called as, superconducting contactless power transfer for EV (SUCPT4EV) system. As the HTS coil has an enough current density and high quality factor Q value, it can deliver a mass amount of electric energy and improved efficiency in spite of a small scale antenna. The SUCPT4EV system has been expected as a reasonable option to improve the transfer efficiency of large electric power. In this study, we examined the improvement of transmission efficiency and properties for HTS transmitted antenna coils within 40cm distance at radio frequency (RF) generator of 60W, 370kHz. In addition, we achieved impedance matching conditions for different material coils between HTS and normal conductors.

Infrastructure Cost Issues Related to Inductively Coupled Power Transfer for Electric Vehicles

The electrification of vehicles has been accelerated over the last few years due to tighter emission regulations, volatile fuel prices, and progress in standardization as well as improvement of battery technologies. Key hurdles of electric vehicles (EV) to gain a larger share in the automotive market are the cost of the energy storage system (ESS) and the density of the EV charging infrastructure. The achievable range of an EV or full electric driving of a plugin hybrid electric vehicle (PHEV) is limited by its battery capacity. The time to recharge the battery is related to the power level of charging as well as allowable charging parameters to protect the battery life. In order to overcome the constraints of limited range of EVs (all electric driving) as well as the cost of ESS, inductively coupled power transfer (ICPT) is an interesting technology path to be considered, in particular if applied as opportunity (stop-and-go) or in-motion charging (also called dynamic wireless charging or move and charge). In-motion wireless charging could lead to significant reductions of the vehicle-related cost of electrification but this comes with the price of an infrastructure that needs to be built and maintained. In order to design the ICPT infrastructure and calculate the cost of construction and operation, certain assumptions have to be made with respect to the vehicle specifications, the specification of the charging system itself and the cost of integration into the existing road infrastructure. The objective of this paper is to provide a thorough analysis of the cost associated with the implementation of a dynamic ICPT infrastructure to support the operation of electrified vehicles and to present transportation agencies a business model that can provide a starting point for the development of a new EV infrastructure.

MAGNETIC RESONANCE COUPLING BASED WIRELESS POWER TRANSFER FOR CONTACTLESS CHARGING OF ELECTRIC VEHICLES

The availability of a convenient charging mechanism will help greatly in dispersal of Electric Vehicles more widely. The concept of Wireless transfer of electrical energy will make this possible. The feasibility of wireless power transfer for Electric Vehicles by electromagnetic resonance coupling is investigated in this paper. The experiment is carried out on small sized antennas that can be equipped at the bottom of a vehicle. The efficiency characteristics of power transmitted wirelessly are analyzed by varying frequency of power, gap between receiving and transmitting coils and power to be transmitted. The feasibility of wireless power transfer with large air gaps and high efficiency by small sized antennas is proposed and analyzed in this paper.

Study on Topology Design of Wireless Power Transfer for Electric Vehicle Based on Magnetic Resonance Coupling

Wireless power transfer (WPT) is required for the diffusion of Electric Vehicle (EV) because it makes possible the process of automatically charging EV. Magnetic resonance coupling is a new technology for WPT, which can transfer a large amount of energy with high efficiency in middle distance. In this paper the topology design of WPT for EV by using this technology is investigated. Through theoretical analysis we obtain expressions of optimal efficiency with different topologies based on equivalent circuits and define a condition criterion, which is related with load resistance, transmission distance, resonance frequency and coil size. According to the condition criterion we can design the appropriate topology easily to guarantee optimal transmission efficiency. Finally, simulations and experiments show that the defined condition criterion has high sensitivity and the proposed method of designing topology is effective and feasible.