building an electric vehicle: components and construction part 1: volkswagen conversion
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Building an Electric Vehicle: Components and Construction Part 1: Volkswagen Conversion Part 2: Electric Go-Kart Race. Michael D. Kane, PhD (1) Associate Professor of Bioinformatics (2) University Faculty Scholar (3) Chair of Graduate Education - PowerPoint PPT PresentationTRANSCRIPT
Building an Electric Vehicle:Components and Construction
Part 1: Volkswagen ConversionPart 2: Electric Go-Kart Race
Michael D. Kane, PhD(1) Associate Professor of Bioinformatics
(2) University Faculty Scholar(3) Chair of Graduate Education
Department of Computer and Information Technology
(4) Lead Genomic ScientistBindley Bioscience Center at Discovery Park
Purdue UniversityWest Lafayette, Indiana, USA
evw.tech.purdue.edu
1. range: function of energy density of the battery.Compare gasoline @ 12,000 (theo.) / 2600 Wh/kgwith the lead-acid battery @ 175 (theo.) / 35 Wh/kg
2. time to refuel: charge 40 kWh in 5 minutes?220 V × 2200 A!!!When you pump gasoline @ 20 /min,your energy transfer rate is about 10 MW!(Hint: energy density of gasoline is 10 kWhth/.)
3. cost:(a) light but safe means higher materials costs,e.g., less steel, more aluminum; and higher processing costs,e.g., fewer castings, more forgings...(b) to reduce load on the battery requires high efficiency appliances = costly(c) low cycle life — batteries priced @ $4,000 to $8,000lasting about 2 years
Problems with EV propulsion
Specific Energies of Battery Chemistries
(Wh/kg) (MJ/kg)lead acid 35 0.13NiCd 45 0.16NaS 80 0.28NiMH 90 0.32Li ion 150 0.54gasoline 12,000 43
NOTE: 1 Wh/kg storage capacity equals about 1 mile driving range
Specifications & Performance:
http://evw.tech.purdue.eduDrive system: 72 volts (lead acid)Top Speed: 40 mphDistance: 25 milesCost: $5,000 (total)
Vehicle: $1,500Batteries: $700Electronics: $2,000Batt Chargers: $500Mechanical: $300
Original VW Motor: 150 pounds (70 kg)55 hp
Conversion to Electric Motor: 70 pounds (30 kg)27 hp*200 pounds (90 kg) in batteries.
Conversion is +120 pounds (55 kg)
* The electric motor used in the conversion is rated at 15 hp (peak), but calculating horse-power in an electric motor is different than an internal combustion engine.
Contactor: A relay that closes the “drive batteries” circuit (i.e. turns the vehicle “on”)
Throttle Box
Controller
Shunt
Throttle and Controllers
Configuration: 5 k ohm sealed pot without 3-terminal microswitch
Conection: 4 foot long, 2-wire unshielded, #22 AWG cable
Stroke: Spring-returned lever arm drilled for variable throw distances
Metal Parts: Corrosion-resistant stainless steel
Dimensions: 3.75" H X 4.00" W X 2.06" D
Configuration:
5 k ohm sealed pot with 3-terminal microswitch
Connectons: Potentiometer: 4 ft. long, 2-wire unshielded, #22 AWG cableMicroswitch: Three 0.188" X 0.018" tabs
Stroke: Spring-returned lever arm drilled for variable throw distances
Metal Parts: Corrosion-resistant stainless steel
Dimensions:
3.75" H X 4.00" W X 2.06" D
Throttle Controls
Batteries : 6 x 12V lead-acid deep-cycle AND 1 x 12V for accessories
Controller
Used in the VW conversion
Used in the EV Go-Kart
Controller (Programmable through Software)
Electric Motor
Electric Motor Mount
Gauges
TESLA$110,000
270 hp
EV-Bug$5,00027 hp
Tesla BatteryThe pack weighs 990 pounds, stores 56 kWh of electric energy, and delivers up to 215 kW of electric power, 375 volts. Battery cost is about $30,000
Each cell is 18mm in diameter by 65mm length, The small cell size enables efficient heat transfer, allows for precise charge management, improves reliability, and extends battery pack life. Each cell is enclosed in a steel case which effectively transfers heat away from the cell. The small size makes the cell essentially isothermal, and its large surface area allows it to shed heat to the ambient environment.
Sixty-nine cells are wired in parallel to create bricks. Ninety-nine bricks are connected in series to create sheets, and 11 sheets are inserted into the pack casing. In total, this creates a pack made up of 6,831 cells.
Chassis
Motor mount added to rear
Battery mounts added to sides of cart.
5 x 12V AGM Deep-cycle batteries in parallel
Some carts used lithium iron phosphate batteries (3.3 V)
Controller
Power Switches
Fuses
Contactor
60V system with top speed of about 40 mph, endurance at about 40 laps.
Technology and Innovation
On-board CameraGPS (speed)Lap-top to controllerBlue-tooth helmet
1) Remote desktop to cart PC2) Alter power settings during the race to optimize power/performance3) Video feed sent to Jumbotron (entertainment)4) Audio communications with driver