Electric vehicles are expected to contribute to a better environment and lower dependence on oil and this new boom has already begun. In this paper, the real possibility of electric vehicles and the impact on the Japanese and American automobile industries due to EV development in the future are described. The long history of electric vehicles as future mobility has been paid attention for more than 100 years. The performance of the battery has been the key issue to EV development. As discussed later, however, current battery performance is still completely insufficient compared to the performance of gasoline. So, it is important to clarify what electric vehicles can do and also to know what is impossible to contribute to solve the issues. In a publication by Minami and Chan , titled "Current status and future of electric vehicles", 50 % is used to describe the current technologies of EV and another 50 % is used to write what EV could do. In recent international conferences on electric vehicles, the main theme seems to have shifted from the technological aspects to the ability of EV contribution to the future mobility. Amid concern over the depletion of oil resources, the development of electric vehicles as an important means of transport will support the future of civilization. It is pointed out here that electrification of passenger cars cannot contribute to solving environmental issues in advanced countries. To solve environmental issues of NOx and PM, which are the main issues of environment in advanced countries, it is essential to perform electrification of big trucks and buses, because these are emitted by such heavy duty vehicles. Due to the insufficient performance of batteries, it is difficult to develop electrification of such heavy duty vehicles. One fact is shown based on the data of Japanese and overseas markets of forklifts. It is concluded that the electrification of passenger cars does not contribute to environmental issues and little effort can be made to save the waste of fossil fuels. It is very important for governments and automobile industries to notice what they are expecting about electric vehicles. There have so far been no such political actions in Japan.
Electric vehicles (EVs) are clean due to their zero local emissions and low global emissions. They are also green due to their environmental friendliness, since electricity can be generated by renewable sources. Despite these obvious benefits, EVs have not been widely used around the world; the key reasons are due to their high price, short driving range or lack of charging facilities. With the growing concerns on price fluctuation, depletion of petroleum resources and global warming, there is fast growing interest in EVs in Macau. Thus, it is a pressing need for researchers and power utilities to develop various infrastructures for EV. This paper aims to present a time delay method for EV charging station, by shifting the night-time battery charging within the off-peak period, results are to fill in the valley of the system demand curve.
Interior permanent magnet synchronous motor (IPMSM) systems are vulnerable to uncontrolled generation (UCG) when the inverter switches loss their drive signals suddenly during flied weakening high speed operation. At this point, uncontrolled rectifier is composed by freewheel diodes in the inverter, the current comes from the motor through the rectifier, and then charges the battery. This paper develops a simple analytical model of this system firstly, and then carries out the simulation of UCG transient process to investigate the impact of the motor speed, battery capacity and other factors on UCG and feedback-power obtained throughout the process. Moreover, circuit improvement is presented in order to avoid destruction risk of the battery, motor, inverter and other relevant components during UCG.
The paper presents a surface mounted permanent magnet synchronous machine (SMPMSM) with distributed windings. The main focus of the paper is to provide a new calculation method of electric machine losses, including copper losses and iron losses at load. This method based on the separation of injected current in d-q axes and the developed iron loss models expressing the dependence between the flux density variations and these currents. This calculation is applied not only for an operating point of the machine but for thousands points represented by a driving cycle of a hybrid electric vehicle (HEV). The calculations are taken into account the flux-weakening and the non-linear magnetic material.
With the growing plug-in hybrid electric vehicles (PHEVs) integrated into the power grid, a large number of on-board batteries need to be charged via the infrastructure such as dedicated charging station and the parking lots. In this paper, a control framework is proposed to manage the charging and discharging by using vehicle-to-grid technology. In order to analyze the effect of the PHEV charging to the grid and the corresponding coordinated strategies, this paper describes a simulation model. Initially, the uncontrolled PHEV charging scenarios are performed. The load flow algorithm is applied to calculate the power distribution and power losses on a 33-bus test system. The results indicate the inadequacy of the current power system capacity for the growing electricity demand from PHEVs. Therefore, an optimal control algorithm is derived for PHEV charging and discharging to minimize the total real power loss. Compared to the uncontrolled PHEV charging results, the optimal control algorithm can achieve the maximum loss reduction. Moreover, the voltage drop at each node is limited within a tolerable range while the tightened branch current restrictions are satisfied.
In this paper, a bilateral controller of teleoperated electric vehicle system with time delay is presented using passivity approaches. We showed that the application of wave variable formalism allows the stability of the system in spite of the communication delays and scaling factors between the operator and the electric vehicle. Conditions of the passivity are given and the stability is proved for our teleoperation system. Finally, for demonstration we used the proposed architecture in real network environment.