Drawing Electrical Schematics and Implementing a Student Outreach Program For STAR Charter School

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Yasser Alherz , Mohammed Alsulaiman, Devin
Fredrickson, David Glennon, Kamran Sheikh
Department of Electrical Engineering Computer
Science, Northern Arizona University
performance criteria of an electric vehicle, and
our motor controller will be programmed to
reflect this.


Development of electric vehicles is essential to
reducing pollutants and additionally beneficial
to reducing transportation costs. Part of the
Shell Eco-Marathon was to design the electric
systems of such a vehicle, and our goal was to
optimize efficiency of the vehicles battery
usage. To achieve this we programmed a motor
control system to improve acceleration efficiency
for the SAE-NAU urban concept vehicle. All
components were chosen to work together in order
to optimize efficiency and reliability based on
statistical data gathered about the motor,
potentially increasing battery life up to several
hours in an urban driving environment. Making
electric vehicles more efficient is a key
improvement to the worlds economy and
environment.
For the future on this project, there are plans
to implement real time efficiency mapping of the
torque curve in Figure 3. This differs from the
current auto-acceleration setup in that it is
reactive to the drivers input rather that
pre-programmed. There is also the potential for
construction of a solar charging station for the
battery. This would serve as a better model of
efficiency for future electric vehicles, and
serve as an education research project in energy
generation for the vehicle, as well as also serve
as a showcase with the vehicle.
The Block diagram in Figure 2 shows the basic
layout of the electric subsystems in the vehicle.
Power to the accessories from the accessory
battery is regulated by switches in the dashboard
interface, which also sends signals to the
programmable controller, along with the throttle
and brake switches. This information, in
combination with encoder feedback from the motors
is used to regulate efficient power usage by the
individual motor controllers

• We are very thankful to Dr. Scott for the
  opportunity to work on the Urban Concept Project
  and participate in Shell Eco-Marathon
  competition. The team appreciates the help from
  Dr. Tester, who is our client for the whole
  project. The team would like to thank Dr.
  Venkatraman, who supported the project in many
  technical ways, and also Dr. Kipple who was the
  main advisor for the team.
• The team also would like to give special thanks
  for the generous financial help received from our
  sponsors
• Motor Excellence
• NAPA Auto-parts
• Architectural Environmental Assoc
• Advanced Digital Solutions International, INC
• Encoder Products Co.

The graph shown in Figure 3 below shows the power
consumption (color) of the motor for an applied
torque at a given speed. This information was
used to program efficient drive cycles to be
implemented by the programmable microcontroller
in competition.


Figure 3 Torque Curve
The EE Team is responsible for all electrical
features for the vehicle. The two major
electrical aspects of this project are the
critical drive train system and accessories
required to make the vehicle viable and
efficient. There will be a 12V accessory battery
that will power two headlights, two front turn
signals, two rear brake lights, windshield
wipers, two cooling fans, two rear running lights
that will have integral blinkers, and a horn. In
addition to the accessories, a crucial part in
designing our Shell Eco-Marathon competition
vehicle is electrical power control and
distribution, Figure 1, specifically, the
behaviors of various electrical components.
Efficient power usage of the electric subsystems
is a key
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Figure 1 The motor controllers, bottom, and
electric subsystem control rack, top, of the
Urban Concept EV.