Essay: Electric vehicles

CHAPTER 1
INTRODUCTION
1.1 What is electric vehicle? :
The electric vehicle (EV) is propelled by an electric motor, powered by rechargeable battery packs, rather than a gasoline engine. From the outside, the vehicle does not appear to be electric. In most cases, electric cars are created by converting a gasoline-powered car [1].
The electric car has:
‘ An electric motor.
‘ A controller.
‘ A rechargeable battery.
The electric motor gets its power from a controller and the controller gets its power from a rechargeable battery. Four main parts make up the electric vehicle: the potentiometer, batteries, direct current (DC) controller, and motor. See Figure 1.
Figure 1. An electric vehicle [1]
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1.2 Reason behind getting so much popularity:
‘ It has zero carbon emission which will help to reduce greenhouse effect.
‘ It reduces the burden of demand of conventional fuels like petrol diesel and oil.
‘ To promote sustainable new technology, government provides Subsidy.
‘ It encourages for utilization of renewable energy resources.
‘ It provides encouragement for the two way energy exchange.
‘ Fast implementation charging and strong battery backups.
‘ It can be implemented to mass transportation which will be much affordable.
1.3 Problems Encountered:
‘ Very high charging time
‘ High number of battery packs
‘ Fast discharging
‘ Can’t be used in hilly area
‘ Starting problem in winter
‘ Battery disposal is also a big concern
1.4 Area of work in the project:
As we see that there are so many problems in the field of electric vehicles or hybrid vehicles but in all the type of vehicles the main problem which is encountered is only one and that is charging time of battery [3].
In each and every type of vehicle till now the technology is just short of reducing the charging or recharging time of the electric vehicles. We have worked on how we can charge the battery in very less time so that the time can be saved as well as the loss can be also neglected. With these considerations we have made our electric car and conduction charger which will provide a lesser time to charge the battery comparing with other present systems.
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CHAPTER 2
LITERATURE REVIRW
As we have already discussed in the introduction part that we are going to work in the field of charging system, we have studied different literature papers and web articles from different automobile companies and we came to know that there are different type of charging systems [3] for different types of vehicles like hybrid vehicles, purely electric vehicles and so on. In the first paper we found that what is basically an electric vehicle [1] and what it contains and its structure. In the second literature paper mainly contains the idea about the cost of electric vehicles including all types of taxes and charging prices [2] etc. and from that it is concluded that EVs are costlier now but by the time the technology will develop and it will be healthier for the environment also and much more cheaper.
An electric vehicle charging station, also called EV charging station, electric recharging point, charging point, charge point and EVSE (Electric Vehicle Supply Equipment), is an element in an infrastructure that supplies electric energy for the recharging of plug-in electric vehicle, including all-electric cars, neighborhood electric vehicles and plug-in hybrids.
As plug-in hybrid electric vehicles and battery electric vehicle ownership is expanding, there is a growing need for widely distributed publicly accessible charging stations, some of which support faster charging at higher voltages and currents than are available from residential EVSEs. Many charging stations are on-street facilities provided by electric utility companies or located at retail shopping centers and operated by many private companies. These charging stations provide one or a range of heavy duty or special connectors that conform to the variety of electric charging connector standards
Fig-2 Nissan Leaf recharging from a NRG Energy eVgo station in Houston, Texas
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‘ Advantages
‘ Protected connections ‘ no corrosion when the electronics are all enclosed, away from water or oxygen in the atmosphere.
‘ Safer for medical implants ‘ for embedded medical devices, allows recharging/powering through the skin rather than having wires penetrate the skin, which would increase the risk of infection.
‘ Durability ‘ Without the need to constantly plug and unplug the device, there is significantly less wear and tear on the socket of the device and the attaching cable.
‘ No e-waste
‘ Non radiative energy transfer
‘ Disadvantages
‘ Lower efficiency, waste heat ‘ The main disadvantages of inductive charging are its lower efficiency and increased resistive heating in comparison to direct contact. Implementations using lower frequencies or older drive technologies charge more slowly and generate heat within most portable electronics.
Next two articles contains the concept of smart grid [8,9] through which one can supply the power which is in the EV to the system and can earn too at the same time. This concept is not in the routine life till now but so many experiments have been done by the researchers and hey got success in this concept. A smart grid is an electricity network that incorporates a suite of information, communication and other advanced technologies to monitor and manage the transport of electricity from all generation sources to meet the varying electricity demands of end-users. Smart grids allow for better co-ordination of the needs and capabilities of all generators, grid operators, end-users and electricity market stakeholders in operating all parts of the system as efficiently as possible, minimizing costs and environmental impacts while maximizing system reliability, resilience and stability.
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CHAPTER 3
PROBLEM DEFINITION
Electric Vehicles are having too many advantages over hybrid vehicles and other IC engine vehicles but with that it has many problems or drawbacks too, like the charging time of electric vehicles is too much high as it is of 6-8 hours normally through charger. EVs are not cost efficient now a days so everyone can’t afford it. So it is not economical. EVs are using Li-Ion batteries for their power storage purpose and the disposal of these batteries is again a major concern as it is very harmful to the environment and all the living creatures.
EVs are not as fast as the IC engine vehicles and the highest speed is also somewhat lesser than the IC engine vehicles. In the hilly areas the EVs are not as much capable of withstanding the load as IC engine vehicles can. Battery capacity of EVs is also very low and if we will increase the battery capacity then the weight of the EV will also increase again which is a disadvantage. The transportation is also not so sustainable. As there is motor in the construction we can use either AC or DC motor. Almost 80-85% EVs are having BLDC (brushless DC motor) but some automobile companies use AC motors instead of BLDC motor through which they get high speed but the cost is also increased. So which motor should be used is also the main concern.
As it can be seen that there are so many problems in the EVs but we will work on only one problem because in such a short time period it is extremely hard to work on all the problems together so we will try to sort out only one problem which is conduction charging of EVs with the reduced time for charging.as normal charger can take almost 6-8 hours to charge fully EVs while the new technology of conduction charging can charge the vehicle in the minutes. So it will be time consuming and better for the users also.
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4. Methodology
4.1 Conductive Charging
‘ Conductive charging requires a physical connection between the electronic device’s battery and the power supply. The need for a metal-to-metal connection between the chargers. In this type of charging system charger is provided to charge the rechargeable battery as shown below,
‘
Figure 3 Public charging stations in a parking lot near Los angelus airport. Shown are two old/obsolete (6kW level-2) EVSE units (left: inductive Magne-charge gen2 SPI, right: conductive EVII ICS-200 AVCON).
‘ Subtypes of conductive charging
‘ Based on supply
a) AC charging by charger
b) DC charging by charger
‘ Based on Location
a) Residential(Household) charging
b) EV charging station
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4.2 COMPARISON BETWEEN AC & DC CHARGING
Table 1 Comparison between ac & dc charging
Charging time for 100 km of BEV range Power supply Voltage Max current 6’8 hours Single phase – 3.3 kW 230 VAC 16 A 2’3 hours Three phase – 10 kW 400 VAC 16 A 3’4 hours Single phase – 7 kW 230 VAC 32 A 1’2 hours Three phase – 22 kW 400 VAC 32 A 20’30 minutes Three phase – 43 kW 400 VAC 63 A 20’30 minutes Direct current – 50 kW 400 – 500 VDC 100 – 125 A 10 minutes Direct current – 120 kW 300 – 500 VDC 300 – 350 A
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4.3 Residential charging
Mode 1: Household socket and extension cord
Mode 1 : Fixed, non-dedicated socket.
The vehicle is connected to the power grid through standard socket-outlets present in residences, which depending on the country are usually rated at around 10 A. To use mode 1, the electrical installation must comply with the safety regulations and must have an earthing system, a circuit breaker to protect against overload and an earth leakage protection. The sockets have blanking devices to prevent accidental contacts.
The first limitation is the available power, to avoid risks of
‘ heating of the socket and cables following intensive use for several hours at or near the maximum power (which varies from 8 to 16 A depending on the country)
‘ fire or electric injury risks if the electrical installation is obsolete or if certain protective devices are absent.
The second limitation is related to the installation’s power management
‘ as the charging socket shares a feeder from the switchboard with other sockets (no dedicated circuit) if the sum of consumptions exceeds the protection limit (in general 16 A), the circuit-breaker will trip, stopping the charging.
All these factors impose a limit on the power in mode 1, for safety and service quality reasons. This limit is currently being defined, and the value of 10 A appears to be the best compromise.
Mode 2: Domestic socket and cable with a protection device
Mode 2 : Non-dedicated socket with cable-incorporated protection device.
The vehicle is connected to the main power grid via household socket-outlets. Charging is done via a single-phase or three-phase network and installation of an earthing cable. A protection device is built into the cable. This solution is more expensive than Mode 1 due to the specificity of the cable.
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Mode 3: Specific socket on a dedicated circuit
Mode 3: Fixed, dedicated circuit-socket.
The vehicle is connected directly to the electrical network via specific socket and plug and a dedicated circuit. A control and protection function is also installed permanently in the installation. This is the only charging mode that meets the applicable standards regulating electrical installations. It also allows loadshedding so that electrical household appliances can be operated during vehicle charging or on the contrary optimize the electric vehicle charging time.
Mode 4: Direct current (DC) connection for fast recharging
Mode 4 : CC Connection.
The electric vehicle is connected to the main power grid through an external charger. Control and protection functions and the vehicle charging cable are installed permanently in the installation.
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4.4 ELECTRIC CAR BATTERY CHARGER
Figure 4 Electric vehicle charger
WORKING
When a 230v supply is given to the step down transformer it will convert it into the 12v.9v battery will supply power which will be converted to 5b through IC7805 and it will work as transmitter. At the receiving end receiver will receive the signals and turn on the relay which will transfer the 12v supply to the battery and hence the battery will be charged. When battery will be fully charger the indicator will glow.
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4.5 Circuit diagram of charger
Figure 5 Circuit diagram of EV Charger
Components Used in the Charger
‘ IC LM358 ‘ 1 no
‘ IC 7805 ‘ 1 no
‘ IR Transmitter ‘ 1 no
‘ IR Receiver ‘ 1 no
‘ 10??f Capacitors ‘ 2 nos
‘ 9V Battery ‘ 1 no
‘ Preset ‘ 3 no
‘ LED ‘ 2 nos
‘ 10K Resistor ‘ 2 nos
‘ 1K Resistor ‘ 2 nos
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Description of components
‘ IC LM358
The LM358 datasheet specifies that it consists of two independent, high gain, internally frequency compensated operational amplifiers which were designed specifically to operate from a single power supply over a wide range of voltages. Operation from split power supplies is also possible and the low power supply current drain is independent of the magnitude of the power supply voltage.
‘ IC 7805
A regulated power supply is very much essential for several electronic devices due to the semiconductor material employed in them have a fixed rate of current as well as voltage. The device may get damaged if there is any deviation from the fixed rate.
‘ 0-12v 1.5Amp transformer
This is a step down transformer which converts the 230v supply in to the 12v supply. Its readings are 0-12v 1.5Amp transformer.
Figure 6 Step down Transformer
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5. Other related technologies
‘ Smart grid communication
Recharging a large battery pack presents a high load on the electrical grid, but this can be scheduled for periods of reduced load or reduced electricity costs. In order to schedule the recharging, either the charging station or the vehicle can communicate with the smart grid. Some plug-in vehicles allow the vehicle operator to control recharging through a web interface or smartphone app.[63] Furthermore, in a Vehicle-to-grid scenario the vehicle battery can supply energy to the grid at periods of peak demand. This requires additional communication between the grid, charging station, and vehicle electronics. SAE International is developing a range of standards for energy transfer to and from the grid including SAE J2847/1 “Communication between Plug-in Vehicles and the Utility Grid”.[64] ISO and IEC are also developing a similar series of standards known as ISO/IEC 15118: “Road vehicles — Vehicle to grid communication interface”.
‘ Renewable electricity and RE charging stations
Charging stations are usually connected to the electrical grid, which often means that their electricity originates from fossil-fuel power stations or nuclear power plants. Solar power is also suitable for electric vehicles. SolarCity is marketing its solar energy systems along with electric car charging installations. The company has announced a partnership with Rabobank to make electric car charging available for free to owners of Tesla Motors’ vehicles traveling on Highway 101 between San Francisco and Los Angeles. Other cars that can make use of same charging technology are welcome.[65]
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Figure 7 Several Chevrolet Volts at a charging station powered with solar panels in Frankfort, Illinois.
‘ SPARC station
The SPARC (Solar Powered Automotive Recharging Station) uses a single custom fabricated monocrystalline solar panel capable of producing 2.7 kW of peak power to charge pure electric or plug-in hybrid to 80% capacity without drawing electricity from the local grid. Plans for the SPARC include a non-grid tied system as well as redundancy for tying to the grid through a renewable power plan. This supports their claim for net-zero driving of electric vehicles.
‘ E-Move charging station
The E-Move Charging Station is equipped with eight monocrystalline solar panels, which can supply 1.76KWp of solar power. With further refinements, the designers are hoping to generate about 2000KWh of electricity from the panels over the year.[66]
‘ Wind-powered charging station
In 2012, Urban Green Energy introduced the world’s first wind-powered electric vehicle charging station, the Sanya SkyPump. The design features a 4 kW vertical-axis wind turbine paired with a GE WattStation. [67]
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6. CONCLUSION
As we have succeeded in making Charger for electric vehicle of 12v battery, the same concept can be applied in the Electric or hybrid cars but the only difference will be that the ratings and specifications will be changed and after that we can easily able to fully charge the electric car in 10 minutes as shown in the table. By this we also can say that the charging system for this electric vehicle is far cheaper than the wireless charging or the supercapacitor charging. The IC engine cars can also costlier if we compare the new technology loaded electric or hybrid cars. The fuel cost and the maintenance charge is also much lesser.
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REFERENCES
[1.] Electric Cars: Effect on the Environment. (1998) Retrieved January 31, 2010 from http://library.thinkquest.org/20463/environment.html.
[2.] Cassen, C., Hourcade, J.-C., Sassi, O., & Vogt-Schlib, A. (2009, Octobre). Electric vehicles: What economic viability and climate benefits in contrasting futures? Nogent-sur-Marne, France: Centre International de Recherche sur L’Environnementet le D??veloppement (CIRED).
[3.] 7182.Chan CC, Wong YS, “Electric vehicles charge forward”,IEEEPower and Energy Magazine Nov/Dec 2004, pp. 24’333.
[4.] LalitKumar , ShailendraJain, “Electric propulsion system for electric vehicular technology: A review”, Renewable and Sustainable Energy Reviews 29(2014), pp. 924’9404.
[5.] Siang FuiTie, CheeWei Tan, “A review of energy sources and energy management system in electric vehicles”, Renewable and Sustainable Energy Reviews 20 (2013), pp. 82-1025.
[6.] Texas Instruments Application note, “Hybrid and Electric Vehicle Solutions Guide” 6. James Gover,”ATutorial on Hybrid Electric Vehicles: EV, HEV, PHEV and FCEV”
[7.] Boots, M., Thielens, D., Verheij, F. (2010), International example developments in Smart Grids – Possibilities for application in the Netherlands, confidential report for the Dutch Government, KEMA Nederland B.V., Arnhem.
[8.] Deloitte Consulting (2010). ‘Gaining Traction: A Customer View of Electric Vehicle Mass Adoption in the US Automotive Market.’ Deloitte Consulting LLP, 2010.
[9.] Lorico, A., J. Taiber and T. Yanni (2011). “Inductive Power Technology System Integration for Battery-Electric Vehicles.” Clemson University International Center for Automotive Research. Presented at International Conference on Sustainable Automotive Technologies, 2011.
[10.] Miller, Paul (2009-01-08). “Palm Pre’s wireless charger, the Touchston”.Engadget.