1. ECE 477 Senior Design Group 12  Spring 2006 Daniel da Silva Atandra Burman Eric Aasen Harsha Vangapaty

3. Outline Project overviewProject overview Design challenges facedDesign challenges faced ECE 362 knowledge usedECE 362 knowledge used

4. Project Overview Maximum Power Point Tracker (MPPT) : DC to DC converter that converts the input voltage from a solar cell array to the output voltage of a battery pack.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” alongOptimum “power point” along current vs. voltage curve that produces power for solar array. Our tracking algorithm will provideOur 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.Relay data to the telemetry unit and driver interface system on the solar car via the CAN bus.

5. Design Challenges Faced Board sizeBoard size –Board area must be no larger than 1.8” by 3.0” EfficiencyEfficiency –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 AccuracyHigh 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

6. ECE 362 Knowledge Used Understanding and implementing ISA of a microcontrollerUnderstanding and implementing ISA of a microcontroller Buffer I/O handlingBuffer I/O handling Interrupt HandlingInterrupt Handling Analog-to-Digital ConverterAnalog-to-Digital Converter –Convert input voltage, current and temperature PWMPWM –Controls conversion ratio of DC-DC converter board SPISPI –Load the CAN address of the device, detect cables, send various flags to diagnostic LEDs

7. Project Demo Demo shown in conjunction with the other two Solar teams.Demo shown in conjunction with the other two Solar teams.

8. ECE 477 Senior Design Group 13  Spring 2006 Matt Cozza, Joe Waugh, Evan Zelkowitz, Elmer Chao

9. Outline Project overviewProject overview Design challenges facedDesign challenges faced ECE 362 knowledge usedECE 362 knowledge used Project demoProject demo

10. 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.Interfaces with Motor Controller, Battery Pack, Packet Modem, PowerPoint trackers, and Driver Interface System. Gathers temperature, acceleration, and GPS data.Gathers temperature, acceleration, and GPS data. Transfers information out to Driver Interface System and Packet Modem.Transfers information out to Driver Interface System and Packet Modem.

11. Design Challenges Faced Integrating with motor controller, battery system, GPS module, driver interface system, and power point trackersIntegrating with motor controller, battery system, GPS module, driver interface system, and power point trackers CAN protocolCAN protocol PIC processor and compiler quirksPIC processor and compiler quirks –Banked memory –Compiler “issues”

12. ECE 362 Knowledge Used Register settingsRegister settings Microcontroller SPI port operations and UARTMicrocontroller SPI port operations and UART Timers and interruptsTimers and interrupts

13. Project Demo Demo shown in conjunction with the other two Solar teams.Demo shown in conjunction with the other two Solar teams.

14. ECE 477 Senior Design Group 14  Spring 2006 Jason, Nathanael, David, David

15. Outline Project overviewProject overview Design challenges facedDesign challenges faced ECE 362 knowledge usedECE 362 knowledge used Project demoProject demo

16. Project Overview Driver interface for Solar Racing TeamDriver interface for Solar Racing Team Communication with onboard power trackers and telemetry board via CAN busCommunication 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)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 LCDDisplay speed, battery power, and other information on the LCD

17. Design Challenges Faced Low Power RequirementsLow Power Requirements –Used high efficiency switching regulator OrCAD bug with overlapping nets on different layersOrCAD bug with overlapping nets on different layers I2C bus needs pull up resistorsI2C bus needs pull up resistors PLDs are smallPLDs are small –had to move functionality to microcontroller

18. Design Challenges Faced Component Datasheets (configuration/usage information buried deep)Component Datasheets (configuration/usage information buried deep) –Such as LCD requires few seconds to boot up Controlled Area Network (CAN) communication protocolControlled Area Network (CAN) communication protocol –Send/Receive CAN messages Useable Menu SystemUseable Menu System

19. ECE 362 Knowledge Used Assembly Language (and embedded C)Assembly Language (and embedded C) Software/Hardware Debug skillsSoftware/Hardware Debug skills On-Chip PeripheralsOn-Chip Peripherals –I2C serial interface (LCD communications) –A/D Module (Temperature and Diagnostics) –Timers (Timeouts, CAN interrupts) –SCI (RS232) –Software Debouncing

20. Project Demo LinkLinkLink

21. Questions / Discussion