Design Solutions Sponsored by: National Science Foundation Advisors: Abdullah Eroglu, Hosni Abu-Mulaweh, Hossein Oloomi Team Members: Mitchell Eilerman, Leandra Lee, Charles McIntosh, Josh Weaver, Andres Cobos, Austin Swihart March 19, 2015 IPFW Electric Vehicle

Project Overview  Electrically powered vehicle with solar recharge  Uses data and equipment from previous senior design projects  Bipolar DC-DC converter with four quadrant topology  Solar Panel  Mini-Baja frame

Project Overview  Project’s Final Goals:  Reach speed of 10 mph in 15 seconds time  Achieve Driver Controlled Speed  Design Cooling System  Provide information display  Stay within $1000 budget

Project Diagram

Subsystems  DC-DC Converter  Control System  Cooling System  Charging System

DC-DC Converter Concepts  Decoupling capacitors  Decoupling capacitors and shielding  Decoupling capacitors, shielding, separate Arduino from MOSFET drivers, and reduce the length of the wires

Concept 1: Decoupling capacitors Advantages:  Drastically reduces switching noise  Relatively simple design Disadvantages:  Consume more space  High Cost

Concept 2: Decoupling capacitors & shielding Advantages:  Least expensive solution  No relocation of components Disadvantages:  Consumes space  System more unwieldy Wires Arduino microcontroller

Concept 3: Decoupling capacitors, shielding, separate Arduino from MOSFET drivers, and reduce the length of the wires Advantages:  Less affected by interference from MOSFET drivers  May be placed closer to any needed sensors Disadvantages:  There may not be space  Longer wires cause additional power loss  Longer wires introduce additional noise MOSFET drivers Arduino microcontroller

Control System Concepts  Pedal press linear with speed  Pedal press linear with voltage  Two-state system: acceleration and constant speed

Concept 1:Pedal press linear with speed Advantages:  More accurate control of speed  Pedal scheme relatively easy to learn Disadvantages:  Significant testing required

Concept 2: Pedal press linear with voltage Advantages:  Control code already designed for application Disadvantages:  Harder for driver to control vehicle speed

Concept 3: Two-state system: Acceleration and constant speed Advantages:  Accelerates at set rate  Easier to maintain speed Disadvantages:  Cannot directly control acceleration  Steep learning curve

Cooling system  Forced convection by use of fans  Radiator with a water jacket  Fin and fan combination

Concept 1: Forced convection by use of fans Advantages:  Simple and easily implemented  Reliable, low maintenance and inexpensive  Can affect a large area of components  Free convection changed to forced convection  Can remove variable amount of heat Disadvantages:  Relies on the ambient air

Concept 2: Radiator with a water jacket Advantages:  High capacity for heat removal  More easily controlled Disadvantages:  Components will require a partial disassembly to maintain  Potential safety issues  Requires large amount of energy from batteries  More complicated and more maintenance

Concept 3: Fin and Fan combination Advantages:  Low maintenance  Localized heat removal  Low cost Disadvantages:  Relies on ambient air temperature

Charging System Concepts  Use existing 48V booster  Replace booster with 24V booster  Include AC option with either of the previous ideas

Concept 1: Use Existing 48V booster Advantages:  No additional purchasing of parts  Allows batteries to reach peak voltage Disadvantages:  The charge time of the batteries will be increased  Power will be lost  System is dependent on light available

Concept 2: Replace booster with 24V booster Advantages:  Higher efficiency  Charges the batteries faster Disadvantages:  Purchase of a new booster is necessary  System is dependent on light available

Concept 3: Include AC option with either of the previous ideas Advantages:  Charges more quickly if an AC power source available.  Can be charged without light source. Disadvantages:  No longer solely dependent on solar energy  Control system must be developed  Additional space is needed for the system

Cross’s Matrix - DC-DC Converter

Cross’s Matrix - Control System

Cross’s Matrix - Cooling System

Cross’s Matrix - Charging System

Design Decisions

Design Decisions (cont.)

Final Design Decision Primary ConceptSecondary Concept Control SystemPedal press linear with voltagePedal press linear with speed DC-DC ConverterDecoupling Capacitors between sourcesShielding wires leading to Arduino Cooling SystemFins and fansWater jacket Charging System48 V booster24 V booster

Questions?