Illumination Engg

EX- 501 Utilization of Electrical Energy

Unit-VIntroduction to Electric and Hybrid VehiclesUNIT V- Introduction to Electric and Hybrid VehiclesConfiguration and performance of electrical vehicles, traction motor characteristics, tractive effort, transmission requirement, vehicle performance and energy consumption.

Electric carAnelectric caris anautomobilethat ispropelledby oneelectric motoror more, using electrical energy stored inbatteriesor another energy storage device.Electric motorsgive electric cars instant torque, creating strong and smooth accelerationElectric cars are significantly more expensive than conventionalinternal combustion enginevehicles. Hybrid electric vehicles are expensive due to the additional cost of theirbatterypack. Electric cars have several benefits over conventional internal combustion engine automobiles, including a significant reduction of localair pollution.An EV recharged from the grid electricity emits about 115grams ofCO2per kilometer, whereas a conventional Patrol powered car emits 250g(CO2)/kmConfiguration and performance of electrical vehiclesElectric vehicles are divided into two general categories: battery-electric vehicles and hybrid-electric vehiclesA switch to Electric Vehicles would reduce the total primary energy consumed for personal transportation as EVs are more energy efficient than Conventional Vehicles.A Battery EV produces zero vehicular emissions.Hybrid EV leads to more effective emission controls because it is technically easier to control combustion-engine emissions when the engine runs continuously and at a constant output.EV can also reverse direction and convert vehicle motion (kinetic energy) back into energy stores through regenerative brakingSome electric vehicles have very small motors, 15kW some have bigger 55 to 200 KW for more Acceleration.

Battery-electric vehicles

Hybrid Vehicle

Batteries for electric carLead acid batteriesare still the most used form of power for most of the electric vehicles used today.Most current highway-speed electric vehicle designs focus onlithium-ionand other lithium-based batteries.DC Fast Chargingstations recharge battery to 80 percent in about 30 minute.Battery swapping: An alternative to quick recharging is to exchange a discharged battery or battery pack for a fully charged one.Battery life should be considered when calculating the extended cost of ownership, as all batteries eventually wear out and must be replaced.Grainger Center for Electric Machines and Electromechanics University of Illinois at Urbana-Champaign9Why Not Just Big Batteries?Lead-acid battery energy density is only about 1% of that in Patrol.

Electric and Hybrid GalleryGeneral Motors EV1.650 Kg battery pack at 312 V, 102 kW motor.0-60 mph in less than 9 s.

Volvo turbine-basedhybrid prototype.

Electric Car Component

Toyota Hybrid Specs1500 cc engine.Small NiMH battery set, 288 V.40 HP motor, ac permanent magnet type.Continuously-variable transmission with sun-planet gear set for energy control.0-60 mph in about 17 s.Rated 30 Km/ L city, 48 Km/ L highway.12

Electric and Hybrid Car GalleryToyota architecture

Honda architecture:

15Highest power handling: 500 A x 500 V = 250 kW

Adifferentialis a particular type of simpleplanetary gear trainthat has the property that the angular velocity of its carrier is the average of the angular velocities of its sun and annular gears. This is accomplished by packaging the gear train so it has afixed carrier train ratioR = -1, which means the gears corresponding to the sun and annular gears are the same size. This can be done by engaging the planet gears of two identical and coaxialepicyclic gear trainsto form aspur gear differential. Another approach is to usebevel gearsfor the sun and annular gears and a bevel gear as the planet, which is known as abevel gear differential.

A spur gear differential constructed by engaging the planet gears of two co-axial epicyclic gear trains. The casing is the carrier for this planetary gear train.Vehicle performance and energy consumptionElectric vehicles consume less energy than fossil fuel vehicles.An electric vehicle consumes around three times less final energy than a fossil fuel (= petrol, diesel) vehicle with the same weight and the same performance.However, energy is required to produce fossil fuel and electricity, as well as to distribute them. If we include this energy, then fossil fuel vehicles consume Well-to-Wheel 20 to 80% more primary energy than electric vehicles of the same weight and performance, excluding driving range (20% = diesel-lead comparison, 80% = petrol-lithium comparison).Vehicle performanceElectric vehicles generate significantly less CO2 than fossil fuel vehicles.Electric vehicles do not produce emissions and therefore, on a Tank-to-Wheel basis, cause infinitely less pollution than fossil fuel vehicles.If we compare Well-to-Wheel CO2 emissions generated from the source of the primary energy (oil well, mine) to the vehicle, an electric vehicle generates on average, less than half the CO2 of a fossil fuel vehicle of the same weight and performance .Electric vehicles will generally be smaller and lighter and therefore even cleaner and more fuel-efficient.

Petrol-engined, Diesel-engined vehicle

Petrol-engined: Nominally, for each kWh of energy transmitted to the wheels, around 5.6 kWh of petrol in the tank is required Tank-to-Wheel (18% efficiency= 1 kWh) ). This number is higher in most real traffic conditions.Diesel-engined: Nominally, for each kWh of energy transmitted to the wheels, around 4.5 kWh of fuel is required Tank-to-Wheel (22% efficiency = 1 kWh). This number is higher in most real traffic conditions. Electric vehicle with lead-acid batteriesFor each kWh of energy transmitted to the wheels, an average of 1.7 kWh of electrical energy is required Battery-to-Wheel (= 1 kWh / 60%). Nominal Well-to-Wheel consumption: approximately 15 to 39 kWh/100 kmElectric vehicle with lithium batteries For each kWh of energy transmitted to the wheels, an average of 1.4 kWh of electrical energy is required (= 1 kWh / 72%). Nominal Battery-to-Wheel consumption: 12.7 to 20 kWh of electricity/100 kmBenefits of Electric CarRegenerative braking Usingregenerative braking, a feature which is present on manyelectric and hybrid electric vehicles, approximately 20% of the energy usually lost in the brakes is recovered to recharge the batteriesPollution free on road.Smooth driving

Traction motor characteristics

Tractive effortItis theforcegenerated by a vehicle's engine or motor in order to generatemotionthrough tractive force. Tractive effort differs fromtractive force, which is the actual force applied at the road surface, by the amount ofrolling resistancepresent. In mathematical terms-Tractive Effort = Tractive Force + Rolling Resistance

FRP e-rickshaw Indian manufacturedThese rickshaws are built on M.S(Mild Steel)Chassis,consist of 3 wheels with a differential mechanism at rear wheels. The motor is brush less DC motor manufactured mostly in India and China. The electrical system used in Indian version is 48V and Bangladesh is 60V. The body design from most popular Chinese version is of very thin iron or aluminum sheets. Some variants made in fiber are also popular because of their strength and durability, resulting in low maintenance.[7]Body design is varied from load carriers. passenger vehicles with no roof, to full body with windshield for drivers comfort[8]It consist of a controller unit.They are sold on the basis ofvoltagesupplied andcurrentoutput, also the number ofmosfet(metal oxide field effect transistor) used.[8]The battery used is mostlylead acid batterywith life of 612 months.Fuel Cell- an electrochemical energy conversion deviceTo convert the chemicals hydrogen and oxygen into water, and in the process it produces electricity. Battery : the other electrochemical device that we are all familiar. A battery has all of its chemicals stored inside, and it converts those chemicals into electricity too. This means that a battery eventually "goes dead" and you either throw it away or recharge it. For a fuel cellChemicals constantly flow into the cell so it never goes dead.As long as there is a flow of chemicals into the cell, the electricity flows out of the cell. Most fuel cells in use today use hydrogen and oxygen as the chemicals. All fuel cells have the same basic operating principle.Fuel cells consist of an electrolyte material which is sandwiched in between two thin electrodes (porous anode and cathode). The input fuel passes over the anode (and oxygen over the cathode) where it catalytically splits into ions and electrons. The electrons go through an external circuit to serve an electric load while the ions move through the electrolyte toward the oppositely charged electrode. At the electrode, ions combine to create by-products, primarily water and CO2. Depending on the input fuel and electrolyte, different chemical reactions will occur.

An input fuel is catalytically reacted (electrons removed from the fuel elements) in the fuel cell to create an electric current.It consists of three components - a cathode, an anode, and an electrolyte sandwiched between the two. Oxygen from the air flows through the cathodeA fuel gas containing hydrogen, such as methane, flows past the anode. Negatively charged oxygen ions migrate through the electrolyte membrane react with the hydrogen to form water, The reacts with the methane fuel to form hydrogen (H2) & carbon dioxide (CO2).

This electrochemical reaction generates electrons, which flow from the anode to an external load and back to the cathode, a final step that both completes the circuit and supplies electric power. To increase voltage output, several fuel cells are stacked together to form the heart of a clean power generator. Animation of PEMFC

Electrochemical reactions in PAFC At the anode:Hydrogen is split into two hydrogen ions (H+), which pass through the electrolyte to the cathode, and two electrons which pass through the external circuit (electric load) to the cathode. At the cathode: the hydrogen, electrons and oxygen combine to form water.

Problems with Fuel CellsThe fuel cell uses oxygen and hydrogen to produce electricity. The oxygen required for a fuel cell comes from the air. In fact, in the PEM fuel cell, ordinary air is pumped into the cathode. The hydrogen is not so readily available, however. Hydrogen has some limitations that make it impractical for use in most applications. For instance, you don't have a hydrogen pipeline coming to your house, and you can't pull up to a hydrogen pump at your local gas station. Hydrogen is difficult to store and distribute, so it would be much more convenient if fuel cells could use fuels that are more readily available. This problem is addressed by a device called a reformer. A reformer turns hydrocarbon or alcohol fuels into hydrogen, which is then fed to the fuel cell. BANSAL INSTITUTE OF SCIENCE AND TECHNOLOGY BHOPALASSIGNMENT NO : 5DEPT : EXSESSION : JULY - DEC 2014Electrical and ElectronicsSUBJECT: UEEUtilization of Electrical EnergyCODE501SEM: VSECTION: A & BFACULTYM.K.MaluISSUE DATE: 15/10/15 SUBMISSION DATE:2/11/15RETURN DATE: 5/11/15

Explain with sketches three important methods of transmission of mechanical power from traction motor to the driving wheel. Give essential electric and mechanical characteristics of traction motor.What is vehicle performance and energy consumption?