Transcript bonus_presentation_f..

ECE 477 Senior Design
Group 12  Spring 2006
Daniel da
Silva
Atandra
Burman
Eric
Aasen
Harsha
Vangapaty
Outline
• Project overview
• Design challenges faced
• ECE 362 knowledge used
Project Overview
Maximum Power Point Tracker (MPPT) :
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DC to DC converter that converts the input voltage from a solar cell
array to the output voltage of a battery pack.
Optimum “power point” along
current vs. voltage curve that
produces power for solar array.
Our tracking algorithm will provide
control of the DC to DC converter by
adjusting the duty cycle on the PWM
in order to achieve this power point.
Relay data to the telemetry unit and driver interface system on the
solar car via the CAN bus.
Design Challenges Faced
• Board size
– Board area must be no larger than 1.8” by 3.0”
• Efficiency
– Car puts out a maximum of 1200W of power
– Critical that most of this power is used for motion of the car
– 8 converters on the solar car, thus 1mW consumed by this tracker
equals 8 mW consumed on the car
• High DC Accuracy
– Critical for finding the maximum power point of the solar array
– Critical for data as, solar array power output and converter
efficiency, gathered by vehicle’s telemetry system
ECE 362 Knowledge Used
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Understanding and implementing ISA of a microcontroller
Buffer I/O handling
Interrupt Handling
Analog-to-Digital Converter
– Convert input voltage, current and temperature
• PWM
– Controls conversion ratio of DC-DC converter board
• SPI
– Load the CAN address of the device, detect cables, send various
flags to diagnostic LEDs
Project Demo
• Demo shown in conjunction with the other
two Solar teams.
ECE 477 Senior Design
Group 13  Spring 2006
Matt Cozza, Joe Waugh, Evan Zelkowitz, Elmer Chao
Outline
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Project overview
Design challenges faced
ECE 362 knowledge used
Project demo
Project Overview
Our team designed and created a telemetry
board for the Purdue Solar Racing team
• Interfaces with Motor Controller, Battery
Pack, Packet Modem, PowerPoint trackers,
and Driver Interface System.
• Gathers temperature, acceleration, and GPS
data.
• Transfers information out to Driver Interface
System and Packet Modem.
Design Challenges Faced
• Integrating with motor controller, battery
system, GPS module, driver interface
system, and power point trackers
• CAN protocol
• PIC processor and compiler quirks
– Banked memory
– Compiler “issues”
ECE 362 Knowledge Used
• Register settings
• Microcontroller SPI port operations and
UART
• Timers and interrupts
Project Demo
• Demo shown in conjunction with the other
two Solar teams.
ECE 477 Senior Design
Group 14  Spring 2006
Jason, Nathanael, David, David
Outline
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Project overview
Design challenges faced
ECE 362 knowledge used
Project demo
Project Overview
• Driver interface for Solar Racing Team
• Communication with onboard power trackers
and telemetry board via CAN bus
• Allow driver to navigate through a text-based
interface to issue commands to the solar
battery chargers (power trackers)
• Display speed, battery power, and other
information on the LCD
Design Challenges Faced
• Low Power Requirements
– Used high efficiency switching regulator
• OrCAD bug with overlapping nets on different layers
• I2C bus needs pull up resistors
• PLDs are small
– had to move functionality to microcontroller
Design Challenges Faced
• Component Datasheets (configuration/usage
information buried deep)
– Such as LCD requires few seconds to boot
up
• Controlled Area Network (CAN)
communication protocol
– Send/Receive CAN messages
• Useable Menu System
ECE 362 Knowledge Used
• Assembly Language (and embedded C)
• Software/Hardware Debug skills
• On-Chip Peripherals
– I2C serial interface (LCD communications)
– A/D Module (Temperature and Diagnostics)
– Timers (Timeouts, CAN interrupts)
– SCI (RS232)
– Software Debouncing
Project Demo
• Link
Questions / Discussion