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- 1. Hybrid Electric Vehicles By:GOPAL CHANDRA MAHATO
- 2. Module-1:Introduction to HybridElectric Vehicles and Conventional Vehicles Introduction to Hybrid Electric Vehicles: History of hybrid and electric vehicles, social and environmental importance of hybrid and electric vehicles, impact of modern drive-trains on energy supplies; Conventional Vehicles: Basics of vehicle performance, vehicle power source characterization, transmission Characteristics, mathematical models to describe vehicle performance.
- 3. What is anHEV? HEV – Hybrid Electric Vehicle A vehicle that has two or more energy conversion technologies combined with one or more energy storage units
- 4. Possible combinationsinclude diesel/electric, gasoline/fly wheel, and fuel cell (FC)/battery Typically, one energy source is storage, and the other is conversion of a fuel to energy. The combination of two power sources may support two separate propulsion systems. Thus to be a True hybrid, the vehicle must have at least two modes of propulsion.
- 6. For example,a truck that uses a diesel to drive a generator, which in turn drives several electrical motors for all-wheel drive, is not a hybrid. But if the truck has electrical energy storage to provide a second mode, which is electrical assists, then it is a hybrid Vehicle.
- 7. History of hybridand electric vehicles The story begins in Scotland in 1839, where Robert Anderson claims to have built the World’s first electric vehicle in his workshop in Aberdeen. Technology at the time severely limited both range and speed of any electric model, a problem Sir David Salomon encountered in 1870 with the development of his electric protoype – which used a light electric motor but very heavy storage batteries. Driving speed and range were therefore poor.
- 8. The firsthybrid car was built in the year 1899 by engineer Ferdinand Porsche. Called the System Lohner-Porsche Mixte, it used a gasoline engine to supply power to an electric motor that drove the car's front wheels. The Mixte was well-received, and over 300 were produced. In 1904, Henry Ford developed his range of low-price, light weight petrol-powered cars, later to include the Model T, significantly enough that within a few years the Electric Vehicle Company went bust. Electric and hybrid vehicles continued to develop, however, and in 1916 two electric vehicle makers – Baker of Cleveland and Woods of Chicago – both bought hybrid cars to market. Woods claimed that its hybrid model reached a top speed of 35mph and achieved fuel efficiency of 48mpg (miles per gallon). However, it was more expensive and less powerful than its petrol-powered competition, and therefore sold poorly – just six hundred were made.
- 9. The massmarket for petrol vehicles exploded in the US in the 1920’s and 30’s as local and federal governments developed roads across the country. By 1935 the electric vehicle had all but disappeared. Fast forward to the 1960’s, though, and the electric and hybrid vehicle was set to return in a big way. In 1966 U.S. Congress introduced its first bills recommending the use of electric vehicles in order to reduce air pollution – which had steadily become a significant problem in many major cities. Two years later, in 1968, three scientists working at components supplier TRW created a practical hybrid powertrain. Designated as an electromechanical system (EMT), its aim was to provide swift vehicle performance with an engine smaller than required by a conventional internal combustion unit. Many of the engineering concepts incorporated in that system are used in today’s hybrids.
- 10. 1973 sawthe introduction of the Arab oil embargo, and with it the price of fuel rocketed. Volkswagen’s ‘Taxi’, a hybrid which allowed switching between the petrol engine and electric motor, logged over 8,000 miles on the road and was shown at car shows throughout the world. Over the next 25 years, auto manufacturers spent billions of dollars on research and development of hybrid technologies. In spite of this, very few vehicles were produced that could both reduce the world's dependence on oil and compete with gasoline vehicles on price and performance. In the late 1990s, a handful of all-electric vehicles were introduced, the GM EV1 and Toyota RAV-4 EV being two examples. These all-electric vehicles failed to attract widespread interest and were soon dropped from production. It wasn't until Toyota released the Prius in Japan in 1997 that a viable alternative to gas-powered vehicles was introduced.
- 11. In 1999,the Honda Insight became the first mass-production HEV released in the United States. The two-door, two-seat Insight may have been first, but it was the Toyota Prius sedan, released in the United States in 2000, that gave hybrid technology the foothold it was looking for. In the years since its United States introduction, the Prius has become synonymous with the term "hybrid." It is the most popular HEV ever produced, and auto manufacturers around the world have used its technology as a basis for countless other vehicles. In this era of ever-increasing environmental awareness, the Prius may be in for some stiff competition. Honda released the second-generation Insight, and Chevrolet introduced of the Volt. As hybrid technology continues to improve, it will continue developing an even stronger foothold in the world's auto market. Whatever the future holds, one thing is certain, auto manufacturers will keep developing and building hybrids, just as they have all along.
- 12. The nextchange that consumers should expect to see in the next few years is automakers producing plug-in versions of hybrid vehicles that are able to operate at an extended range in all-electric mode. While consumers have modified current versions of hybrid vehicles to be plug-in models, there are currently no commercially available hybrid cars in a plug-in configuration. Expect the first generation of plug-in hybrids to have a 40 to a 70-mile range in electric-only mode at speeds of up to 50 mph.
- 14. social and environmentalimportance of hybrid and electric vehicles
- 15. Impact of moderndrive-trains on energy supplies
- 16. Impact of moderndrive-trains on energy supplies
- 17. increase in powerdemand?
- 26. Why…Modern Drive Trainson Energy Supplies
- 28. HEV Objectives Objectives theHEV wants to obtain: Maximize fuel economy Minimize fuel emissions Minimize propulsion system cost to keep affordable Maintain acceptable performance with a reasonable cost Reduce the conventional car weight
- 29. HEV Advantages OverConventional Engines Regenerative Braking Reduction in engine and vehicle weight Fuel efficiency is increased Emissions are decreased Cut emissions of global warming pollutants by 1/3 or 1/2 Reduce the dependency on fossil fuels Some states offer incentives with owning an HEV ~2 times more efficient than conventional engines
- 30. Motor Components Drive train Electric Motors/Controllers Electric Energy Storage systems Hybrid power units Transmission
- 31. Motor Components BasicComponents An Armature or Rotor A Commutator Brushes An Axle Field Magnet DC Power Supply Electric Motors/Controllers
- 32. Motor Components Electric Motor/Controllers Advancedelectronics allows the motor to act as a generator Draws energy to accelerate and regenerates the battery when slowing down Motor uses magnets and magnetism to create motion
- 33. Motor Components Electric EnergyStorage Systems Batteries: Lithium Ion and Nickel-metal hydride batteries Ultracapacitors Flywheels
- 34. Motor Components Electric EnergyStorage Systems Desirable attributes: High-peak and pulse specific power High specific energy at pulse power High charge to maximize regenerative braking Long life Challenges: Accurate techniques to determine battery state of charge Develop abuse-tolerant batteries Recycleability
- 35. Motor Components Batteries Nickel-MetalHydride Lithium Ion Current Uses Computer and Medical equipment Laptops and Cell phones Life Cycle Much larger than lead acid batteries Low Current contribution Used successfully in low production of HEVs Challenges High Cost High self-discharge Heat generation Control losses of hydrogen Low cell efficiency Life cycle Cell and battery safety Abuse tolerant Acceptable cost Miscellaneous Reasonable specific energy and power Components are recyclable Abuse-tolerant High specific energy and power High energy efficiency Good high-temperature performance Low elf-discharge Recyclable parts NA
- 36. Motor Components Energy Storage:Ultracapacitors Store energy as an electric charge in a polarized liquid layer between an ionically electrolyte and conducting electrode Primarily used for acceleration, climbing hills and regenerative braking
- 37. Motor Components Energy Storage:Flywheel Store kinetic energy within a rapidly spinning wheel Complex, heavy, and large Contains no acid or hazardous material Not affected by temperature Delivers a smooth flow of power Click for more information on the fly wheel
- 38. Motor Components Charging/Discharging theBattery The following are some links to visually display the characteristics of the motor and engine during different scenarios Driving at low speeds City driving Highway driving Uphill driving Coasting/Slowing/Stopping
- 39. Motor Components Regenerative Braking Whenthe driver brakes, the motor becomes a generator and the kinetic energy generates electricity stored into the battery The Toyota Prius uses about 30% of the heat lost kinetic energy from braking
- 40. Motor Components CompressionIgnition Direct Injection Engines (CIDI) Spark Ignition Engines Gas Turbines Fuel Cells Hybrid Power Units 4 Types:
- 41. Motor Components Hybrid PowerUnits: CIDI Most promising power unit Achieves combustion through compressions without the use of a spark plug High pressure injection of the fuel into the combustion chamber Throttle and heat losses travels into the combustion chamber increasing thermal efficiency
- 42. Motor Components Hybrid PowerUnits: Spark Ignition Runs on an Otto cycle Uses a homogeneous air-fuel mixture before entering the combustion chamber When the combustion chamber is compressed, the spark plug is ignited Controlled by limiting the amount of air allowed into the engine
- 43. Motor Components Hybrid PowerUnits: Gas Turbines Runs on a Brayton cycle A compressor raises the pressure and temperature of the inlet air Air is moved to the burner and fuel is injected and combusted to raise the air temperature Power is produced when the heated pressure mixture is expanded and cooled through the turbine
- 44. Motor Components Hybrid PowerUnits: Fuel Cells Generate electricity through an electrochemical reaction combining hydrogen with ambient air Pure hydrogen or any fossil fuel produced is used as hydrogen- rich gas Water vapor is emitted Click to see an animation of the steps to make electricity from a fuel cell.
- 45. Motor Components ContinuousVariable Transmission (CVT) Automated shifted transmission Manual transmission Traditional automatic transmission with torque converter Transmission 4 Types:
- 46. Motor Components Transmission: CVT Infinitenumber of variable transmissions Currently not able to compete with 4-speed and 5-speed transmissions in size, cost, and reliability Provides seamless, stepless acceleration and deceleration The Toyota Prius uses this
- 47. Vehicle Propulsion Series“Power Assist” Parallel “Range Extender” Dual-Mode: Combination of a series and parallel
- 48. Vehicle Propulsion Series Configuration Smallfuel-burning engine that directly drives an alternator to generate electricity Electricity is stored in the battery or sent the to electric motor When the batteries are drained to a certain level, the engine turns on and recharges the battery
- 49. Vehicle Propulsion Parallel Configuration Twopower paths Hybrid power unit or electric propulsion system or both can power the wheels For long trips the engine is used For hills, acceleration, and high power scenarios the electric motor is used
- 50. Vehicle Propulsion Propulsion Comparison Series ConfigurationParallel Configuration Benefits Engine never idles reducing emissions Engine drives a generator to run at optimal performance Allows a variety of options in mounting the engine Some don’t need a transmission Has more power from simultaneous power from motor and engine Don’t need a separate generator because the motor generates the battery Power is directly coupled to the road so can be more efficient
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- 52. Examples Toyota Prius HondaInsight Electric Motor/Generator /Power Storage Output 273.6V (228 cells @ 1.2V) 144V (120 cells @ 1.2V) Battery Type Nickel-Metal Hydride Nickel Metal Hydride Power Output 33kW @ 5600rpm 10kW @ 3000rpm Transmission ECVT CVT Mileage City/Highway 52/45 61/68 Gasoline Engine Horsepower @ rpm 70hp @ 4500rpm 67h @ 5700rpm Emission Rating SULEV ULEV
- 53. HEV Challenges Energystorage devices with high power-to-energy ratios Frequent shut down and start up of the HEV Reduce the size, weight, and cost Higher efficiency in the conversion of fuel to useful power Advanced configurations for the propulsion system components
- 54. Review What isan HEV? HEV objectives HEV advantages over conventional engines Motor components Vehicle propulsion Examples HEV Challenges
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