Electric vehicle: Types, charging topologies, energy storage management system and applicability micro-grids-A review

With the looming scenario of an alarming rate of conventional energy level depletion, snowballing crude oil prices and ever-increasing environmental constraints, such as global warming and ozone layer depletion, associated with the same, energy efficiency has become a priority numero-uno. A substantial proportion of overall crude oil consumption is dedicated to road vehicle transportation systems. Therefore, battery-powered electric vehicles are becoming ever more popular all over the world in the ongoing scenario. In recent years, electric vehicles, whose requirements have grown rapidly in accordance with green energy demand, are being recognised as a viable alternative to conventional vehicle engines, i.e., internal combustion engines (ICE). Electric vehicles in various configurations and capacities like Pure/ Battery Electric Vehicles (PEV/ BEV), Plug-in Hybrid Electric Vehicles (PHEV), and Fuel-Cell Electric Vehicles (FCEV) are being researched and developed to meet current market demand. Moreover, emphasis is being given to battery technology for electric vehicles to obtain a faster rate of charging and increase the discharging time, i.e., increasing the range of travel in a single charging cycle of an EV battery. Even while electric vehicles have a broad spectrum of applications and requirements, the ongoing research spectrums are also accompanied by some major roadblocks, disadvantages and glitches. These include time-constraint of charging, the longevity of battery lifetime and standardisation. Significant research in recent years has been dedicated towards accelerating the charging time of EV batteries through various mechanisms. Herein, the charging mechanism is typically seen to adopt two major techniques, namely constant current (CC) technique and constant voltage (CV) technique. Furthermore, the charging topologies include unidirectional and bi-directional, wherein vehicle-to-grid and grid-to-vehicle schemes are the present areas of concentrated research. Moreover, in accordance with the available literature, the bi-directional power flow model is clearly seen to have an advantage over the traditional unidirectional power flow topology w.r.t. the charging techniques generally employed for electric vehicles. In this regard, an effective battery management system also becomes indispensable and a comprehendible area of vital research. Research shows that bi-directional topology with the incorporation of microgrids into the scheme forms a highly exciting and comprehendible area of future research and may potentially overcome the existing drawbacks of the schemes and methodologies that are currently being used in an attempt to accelerate the battery charging time and improve the overall working performance of the electric vehicles.