The MGA With An Attitude
MGAguru.com The Electric MGA, from UTA - ET-301J MGAguru.com
Conversion of an MGA to Electric Power by engineering students at UTA
 




1957 MGA Electric Conversion

Team Lead:
Powertrain:
Power System:
Chassis:
Schedule/Budget:
 		Steve Gillespie
Rich Bergs
Jay Krueger
Hank Danford
Chris Pickering




Presentation Overview
  • Project Overview
  • Motor System Comparisons
  • Battery Comparisons
  • Designed Adaption Components
  • Schedule
  • Budget
  • Conclusion
 



Required Performance
  • Able to reach and maintain 40-50 mph
  • A range of 20 miles per charge
  • Able to climb grades
  • Accelerate in a reasonable amount of time
 



Modeling of Vehicle
  • Results of Model
      -Required power output at speed
      -RPM range required of system
      -Effects of added weight to performance
 



Systems Considered
  • Brushed DC
      -System used for comparison: FB1-4001
  • Brushless DC
      -System used for comparison: CaliberEV 32
  • AC
      -System used for comparison: AC42A
 



Brushed DC System
  • Pros
      -Pricing
      -Availability
      -Lowest Voltage
  • Cons
      -Efficiency
      -Maintenance
      -Lowest Voltage
torque & Power vs Speed
 




Brushless DC System
  • Pros
      -Regenerative Braking
      -No Major Maintenance
      -Low Voltage
  • Cons
      -Availability
      -Cost
      -Low Power Output
      -Low Voltage
torque & Power vs Speed




AC System
  • Pros
      -Regenerative Braking
      -No Major Maintenance
      -High Voltage
      -High Power Output
  • Cons
      -Availability
      -Cost
      -High Voltage
torque & Power vs Speed




Performance of Systems

Pewer vs Speed for Vehicle in High Gear

 



Choice of System
  • Brushed DC
      -Top Speed ? 90 mph   -0 to 60 = 10 sec.*
  • Brushless DC
      -Top Speed ? 80 mph   -0 to 60 = 17 sec.
  • AC
      -Top Speed ? 102 mph   -0 to 60 = 15 sec.
 



Battery
  • Hawker Genesis 42EP batteryGenesis 42EP
    Hawker Energy Products, Inc.
  • Size
    LxWxH 7.78 x 6.53x6.72
  • Weight
    33 pounds
  • Power
    394 Wh
  • Cost
    $141.00 Delivered.




Front Battery Box
9 battery box assembly
  • Material
    AISI 1040 CR 16 Gage (1/16”)
  • Size
    LxWxH 21x24x9
  • Box Weight
    24 pounds
  • Assembly Weight
    340 pounds



Behind Seat Battery Box
2 battery box assembly
  • Material
    AISI 1040 CR 16 Gage(1/16”)
  • Size
    LxWxH 10x14x9
  • Box Weight
    10 pounds
  • Assembly Weight
    80 pounds



Rear Battery Box
12 battery box assembly
  • Material
    AISI 1040 CR 16 Gage (1/16”)
  • Size
    LxWxH 21x33x9
  • Box Weight
    31 pounds
  • Assembly Weight
    480 pounds




Front Battery Box Analysis
displacement image
  • Applied Force
    3G =1050 lb
  • Deflection (shown)
    Less than 0.001”
  • Stress
    16.5 kpsi
  • Conclusion
    Stress is below yield strength of material (60 kpsi) by factor of 3.6



Rear Battery Box Analysis

displacement image
  • Applied Force
    3G =1050 lb
  • Deflection (shown)
    Less than 0.006”
  • Stress
    18.7 kpsi
  • Conclusion
    Stress is below yield strength of material (60 kpsi) by factor of 3.2




Battery Summary
  • 25 Batteries connected in series
  • 4 Battery boxes
  • 900 lb of added weight to car
  • 76 mile range at 45 mph
 



Chassis Considerations
MGA rolling chassis
  • Frame is welded, steel box section
  • Cross-braced and has integral suspension mounts
  • Very strong; designed with endurance capacity for racing




Brakes
  • Four wheel drum brakes
    (10 inch)
  • Convert front to disk brakes
    (maybe rear also)
  • MGB parts to upgrade or
    use after market kits
 



Shocks/Springs/Other
 
  • Rebuild or upgrade stock lever shocks (heavy duty shock valves)
  • Upgrade front coil springs and rear leaf springs
  • Add front sway bar (maybe rear also)
  • Polyurethane bushings where applicable
  • Weight Distribution
     -Original Curb Weight 1862 lbf
        = Front 52%
        = Rear 48%
     -Estimated Final Curb Weight 2450 lbf
        = Front 45%
        = Rear 55%




Motor Controller Mounts
  • Mounts to existing brackets in engine compartment
  • AISI 1030 12 gage steel Motor Controller mounting




    • Motor Assembly
    Motor diegram



    Motor Adapter
    Motor adapter diegram



    Motor Shaft

    Motor shaft stress



    Schedule
    • Approximately 1 week behind schedule
       -Air Control Design
       -Regenerative Braking Design
          * Manual from Motor System Needed
        -Motor Mount Design - 25%
          * Final Specifications on Motor Needed
        -Transmission Design - 80%
       -Controller Mounting Design - 80%




    Budget
    • Over Budget
       - Components
          * Motor $291
          * Controller $250
          * Batteries $825
    • Under Budget
       - Components
          * Throttle Pot Box $170
          * Miscellaneous $2,548
          * Materials $1,352
       - Labor
          * Engineering Hours $8,981
    • Bottom Line
       - Budgeted-Spent
          * $74,223 - $63,890 = $10,333




    Conclusion
  • Purpose
  • Motor/Controller
     - Solectria AC42A/UMOC440TF
  • Battery
     - Hawker Genesis G42EP
  • Adaption Components
     - Component Design and Analysis as Complete as Possible
  • Chassis
     - Chassis Modification Not Needed
  • Schedule
     - 1 Week Behind
  • Budget
     - Under By $10,333

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