Various concerns over the environment have led to the emergence of new technologies and products, which are not only fuel efficient, but also minimize harmful emissions without compromising with the performance, safety and cost . The electrification and hybridization of vehicles is a complex task, which involves challenges related to chassis design and layout, vehicle dynamics, system integration, power management and optimization. Since electric and hybrid vehicles are complex systems, the design requires the manufacturer to consider several aspects. While the technology used for propulsion in a number of modern vehicles is through an internal combustion engine, which makes use of fuel and oxidizer, the propulsion technology in electric vehicles makes use of electricity instead of petrol and diesel. One of the greatest advantages of electric vehicles is the option of battery swapping. Electric vehicles also make use of powertrain technology, which allows the conversion of one or multiple forms of energy into mechanical energy thereby enabling propulsion of the vehicle .
Transmission technology also plays a major role in electric vehicles as it is the main agent for managing the output torque and power of the engine. With the help of this technology, the transmission system either increases or decreases the torque as per the user requirement. Electric vehicles make use of automatic transmission systems, which are more advanced when compared to the manual transmission systems in terms of gear sets and engine connection. Depending upon their source of electrical energy, electric and hybrid vehicles have the potential to transform into zero emission vehicles in spite of their limitations . Another significant advantage of electric vehicles is that they have the capability of implementing different methods in order to boost the efficiency of the internal combustion engine.
The technology implemented in electric vehicles enables high controllability, adequate robustness, and higher efficiency during hill climbing and regenerative braking. In electric vehicles, electric motors also serve the purpose of generators during regenerative braking system. This technology reduces the amount of energy lost during the braking process by integrating regenerative and conventional frictional braking systems . Certain electric vehicles make use of fuel-cells, which combine oxygen and hydrogen to generate electricity and water. Fuel-cell electric vehicles are beneficial over those, which use batteries as they include a shorter reactant feeding time and lesser maintenance requirements. Fuel-cells also offer a longer lifetime when compared to the conventional vehicles . The common fuels used in the fuel-cells are ethanol, methanol and hydrocarbons. However, one of the major drawbacks of this technology is the availability of hydrogen supply infrastructure and onboard storage. Other drawbacks include shorter life of the fuel cell and high-cost catalysts for fuel conversion. In terms of power usage, electric vehicles require additional power to overcome the losses of internal conversion and transmission .
Scientists are in the process of designing electric vehicles that operate with artificial intelligence. These vehicles have the potential of taking operational decisions as they contain an automatic guidance system, which works with the help of cables laid beneath the road. However, aspects related to vehicle safety and maintenance is still an unanswered question. Extended-range electric vehicles are another kind of electric vehicles, which make use of battery and a small engine for supplemental power. Since the output power and torque are constant in these vehicles, reliability, emission and efficiency of the vehicle are also optimal . Unlike other forms of electric vehicles, the battery capacity of extended-range electric vehicles is huge and effectively accumulates energy while driving downhill and during vehicle braking. Furthermore, the cost of battery is also low when compared to other battery-powered vehicles.
One of the major advantages of extended-range electric vehicles is that they implement a remarkable technological feature of combining battery electric vehicle with hybrid electric vehicle, thereby enabling long-distance driving . It is surprising to know that China has already been using extended-range electric technology in buses and specific passenger cars . The technology is mostly suitable for public vehicles as they produce fewer emissions and save the environment. Furthermore, in the case of deficient energy, the technology supplies power from the generator driven by power engine, which has the potential to recharge even when the vehicle is stationary. Extended-range electric technology also solves the problem of air-conditioning unlike other electric vehicles. Since the battery lasts for a longer time, the availability of charging stations and replacement batteries is not a major challenge.
References
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