ppt FUNDAMENTAL OF EV-INTRODUCTION OF EV unit-2.pptx

introduction of electric vehicle

1. ELECTRIC VEHICLES

2. Introduction An electric vehicle is one powered by an electric motor rather than a traditional petrol/diesel engine. This electric motor is powered by rechargeable batteries that can be charged by common household electricity

3. History of electric vehicles 1900S –EV car, twice the conventional vehicle. wasn’t until the 1920s that interest in electric cars dwindled. It was Henry Ford who put the nail in the electric car coffin when his company began to mass-produce the Model T. The limited maximum speed of electric cars (up to 30mph) limited their practicality. 1970s and 80s –due to increasing the oil price people search alternate source Tesla ’s Roadster, which went on sale in 2008 As of September 2016, there are more than one million pure electric cars and vans owned globally

4. What are the benefits of electric cars? They produce no tailpipe emissions, so are better for the planet. They are exempt from road tax and from the London Congestion Charge. They often have a smoother drive than petrol cars. They are cheaper to run. Do not need much maintenance, as they have fewer moving parts.

5. ELECTRIC VEHICLES Battery-powered vehicles give off virtually no pollution and offer one of the best options for reducing motor vehicle emissions in polluted cities. The driving range of today's electric cars is limited by the amount of power and the battery can provide. Current batteries take hours to recharge and the cost of electric vehicles is high. Recent developments in electric vehicle technology show much promise for future.

6. Working principle of EVs The inverter (power electronic) takes direct current (DC) electricity from battery and converts it to alternating current (AC) electricity and sends it to the motor. The electric motor (electric machine) uses AC current to create torque (mechanical power) to power the wheels for propulsion.

7. Electric Vehicle Types (1)Battery Electric Vehicle (BEV) (2) Hybrid Electric Vehicle (HEV) (3) Plug-in Hybrid Electric Vehicle (PHEV) (4) Fuel Cell Electric Vehicle (FCEV)

8. Components of EV

9. Battery

10. Motor

11. Control Unit

12. Charging Unit

13. Inverter

14. BMS

15. Driver Interface

16. Layout of EV

17. Block diagram of electric vehicle system

18. BATTERIES The batteries are essential and important part of the EV system. Batteries replace IC engine of the vehicle. ( i) Lead-Acid batteries: Lead-acid batteries can be designed to be high power, inexpensive, safe and reliable. But low specific energy, poor cold temperature performance and short calendar and cycle life are still barriers to their use.

19. (ii) Nickel-cadmium batteries: Although nickel-cadmium batteries used in many electronic consumer products have high specific energy and better life cycle than lead-acid batteries, they do not deliver sufficient power and they are not being considered for EV applications. ( iii) Nickel-metal hydride batteries: Nickel-metal hydride batteries have a much longer life cycle than lead acid batteries and they are safe and abuse-tolerant. These batteries have been used successfully in producing electric vehicles. The main challenges with nickel-metal hydride batteries are their high cost high self-discharge and heat generation at high temperatures, need to control losses of hydrogen and low cell efficiency

20. (iv) Lithium ion batteries The lithium ion batteries have high specific power, high-energy efficiency, good high temperature performance and low self-discharge. Components of lithium-ion batteries could also be recycled. These characteristics make lithium ion batteries suitable for EV applications . However, further development is needed in improvement of calendar and cycle life , higher degree of cell and battery safety, abuse tolerance and acceptable cost. (v) Lithium polymer batteries: Lithium polymer batteries with high specific energy initially developed for EV applications also love the potential to provide high specific power for EV applications. The other key characteristics of the lithium polymer are safety, good cycle and calendar life. The battery could be commercially viable if the cost is lowered and increased specific power batteries are developed.

21. BATTERY CHARGER Batteries are replenished by the battery chargers. The battery charger converts AC power available on our electricity network to DC power stored in a battery. It controls the voltage level of the battery cells by adjusting the rate of charge. It will also monitor the cell temperatures and control the charge to keep the battery healthy. Some EVs have on-board chargers whereas others plug into a charger located outside the vehicle.

22. Electric motors The core element of the EV, apart from batteries, is an electric motor. The electric motors used for automotive applications should have characteristics such as high starting torque, high power density, good efficiency, etc .

23. Brushless DC Motors (BLDC ) These motors have traction characteristics such as high starting torque, high efficiency around 95-98%, etc. They are suitable for high power density design approach. Therefore , they are the most preferred motors for the electric vehicle application due to its traction characteristics. The main drawback is high cost due to permanent magnets.

24. Permanent Magnet Synchronous Motor (PMSM ) This motor is also similar to BLDC motor and it has traction characteristics such as high-power density and high efficiency. The difference is that PMSM has sinusoidal back EMP PMSM is the best choice for high performance applications like cars, buses as it is available with higher power ratings. Most of the automotive manufacturers use PMSM motors for their hybrid and electric vehicles. For example, Toyota Prius, Chevrolet Bolt EV, Ford Focus Electric, Honda Accord, BMW i3, etc. use PMSM motor for propulsion.

25. Three Phase AC Induction Motors The induction motors do not have high starting toque similar to DC series motors. But this characteristic can be altered by using various control techniques and the maximum torque is made available at the starting of the motor. Induction motors are the preferred choice for performance oriented electric vehicles due to its cheap cost. Mahindra Reva e20 uses a three phase induction motor for its propulsion

26. Inverter Inverter is a device that converts DC power to AC power used in an electric vehicle motor. The inverter can change the speed at which the motor rotates by adjusting the frequency of the alternating current. It can also increase or decrease the power or torque of the motor by adjusting the amplitude of the signal.

27. Controller The controller is like the brain of a vehicle, managing all of its parameters. It controls the rate of charge using information from the battery. It also translates pressure on the accelerator pedal to adjust the speed in the motor inverter.

28. Comparison with Internal Combustion Engine

29. Comparison with Internal Combustion Engine

30. Advantages or Merits of Electric Vehicles There is no pollution due to emission. i.e., zero emission. It ensures smooth operation. i.e., vibration and noise is less. Cost of operation is less. Less maintenance is required. It is easy to start the vehicle. It takes up less space on the road. So, they help to reduce traffic congestion.

31. Limitations of Electric Vehicles 1. It has less initial torque. 2. It is more expensive. 3. Frequent recharging of battery is needed and also battery charging needs moretime . 4. The performance is poor. 5. Less variety of vehicles is available in the market.

32. HYBRID VEHICLES The word hybrid means, something is mixed together from two things. Hybrid electric vehicles (HEVs) typically combine IC engine of a conventional vehicle with the battery and electric motor of an electric vehicle. The combination offers low emissions, power, range and convenient fueling of conventional (gasoline and diesel) vehicles and they never need to be plugged in. The inherent flexibility of HEVs makes them well-suited for fleet and personal transportation.

33. Layout of hybrid electric vehicle system

34. Working principle of hybrid vehicles Hybrid electric vehicles are powered by an internal combustion engine and one or more electric motors, which uses energy stored in batteries. A hybrid electric vehicle cannot be plugged in to charge the battery. Instead , the battery is charged through regenerative braking and by the internal combustion engine.

35. HEVs typically consist of an electrical storage device, such as a battery, flywheel, or an ultracapacitor . They also combine this energy storage source with a mechanical device, like an internal-combustion engine (ICE), gas turbine, or a fuel cell. This combination reduces both fuel consumption and tailpipe emissions.

36. 4 different types of Parallel hybrid vehicles Understanding Hybrid Vehicles: The 4 Main Types Mild Hybrids. One of the newest innovations in hybrid technology is that of a “mild” hybrid system Full Hybrids Plug-In Hybrids Electric Vehicles with Range Extender Hybrids .

37. Two types of hybrid configurations are considered: ( A) parallel; ( B) series; and ( C) power-split (parallel/series).

38. Parallel HEV Configuration

39. Parallel HEV Configuration The vehicle can be powered by the gasoline engine working alone, the electric motor by itself, or by both energy converters working together. Power distribution between the engine and motor is designed so that the engine can run in its optimum operating range as much as possible.

40. Series HEV configuration

41. Series HEV configuration A series hybrid is like a battery electric vehicle (BEV) in design. Here , the combustion engine drives an electric generator instead of directly driving the wheels. The generator both charges a battery and powers an electric motor that moves the vehicle. When large amounts of power are required, the motor draws electricity from both the battery and the generator. Series hybrids may also be referred to as  extended-range electric vehicles (EREVs )   or  range-extended electric vehicles (REEVs)   since the gas engine only generates electricity to be used by the electric motor and never directly drives the wheels. Modern examples include the Cadillac ELR, Chevrolet Volt, and  Fisker Karma.

42. Power Split or Combined Series-parallel HEV Configuration

43. Power Split or Combined Series-parallel HEV Configuration The vehicle can be powered by the gasoline engine working alone, the electric motor by itself, or by both energy converters working together. Power distribution between the engine and motor is designed so that the engine can run in its optimum operating range as much as possible.

44. Comparison with Electric Vehicles

45. Comparison with Electric Vehicles

46. Advantages of hybrid vehicles 1 . Hybrid vehicles have lower emissions than conventional vehicles because an electric motor is used with an IC engine which offsets how often the engine is usedand therefore, it reduces the fuel use and emissions. 2. Hybrid vehicles provide better fuel economy as it can go 20-30 kms per litre ofgasoline . 3. Cost of operation is less. 4. As hybrid vehicle requires less fuel to run, it can reduce Nation's dependence onfossil fuels and help to decrease foreign oil imports thereby increasing energy security. 5. Instant torque is obtained during the starting. 6. More reliable and comfortable operation are ensured.

47. Disadvantages of hybrid vehicles 1 . The initial cost will be very high i.e., higher than other cars. 2. Since a lot of batteries will be needed, the car will be very heavy. 3. As there are electrical components, there is a risk of shock during an accident. 4. The vehicle can be repaired only by professionals. Therefore, the maintenancewill be higher. 5. Spare parts will be very costly and rare. 6. Full hybrid vehicle may not be a powerful as conventional vehicle.