Solar Jackets Motor Control

1. Andy Lian Gabriel Miranda Chris McManus Drew Pearson Andrew Perez Solar Jackets Motor Control

2. Project Overview • Design motor control system for the Solar Jackets solar racing vehicle • Continuing work from previous group • Fall 2010 • System responsibilities: • Electric motor operation • Central communication between vehicle subsystems

3. Fall 2010 Project Results • Test bench construction • Safety systems designed and installed • Functioning motor control using serial and analog signals

4. Fall 2010 Project Shortfalls • Effective cruise control • Switch between serial and analog control • Air gap adjustment and control • Effective load testing

5. Technical Objectives • Dynamic control of motor air gap • Functional cruise control using SBC • Regenerative braking • Load testing • Communication with vehicle subsystems

6. Air Gap Adjustment • Air gap between rotor and stator • Adjustable while motor in use • Increase air gap –> Increase top speed/Decrease torque • Decrease air gap –> Decrease top speed/Increase torque • Need highest torque when gap is minimized • 35-40 in-lb (640 oz-in)

7. Air Gap Motor – Option 1 • Stepper Motor • Planetary Gear Set • Specs • ~120 oz-in • 4.5” L x 3.2” H x 2.2” W • 12 VDC • SBC Control • Pricing • Motor: $227-$336 • Gearbox: $452-$589

8. Air Gap Motor – Option 2 • Window Lift Motor • FIRST Robotics • Specs • 82 in-lb • 12 VDC • Pricing • $60-$80

9. Air Gap Motor - Comparison

10. Controller Inputs - Discrete • All I/O except serial interface lines • Serial used to check status of controller

11. Controller Inputs - Serial • Configures controller • Provides all inputs • Checks controller status

12. Controller Mode Issue • Controller prevents change from serial to discrete or vice-versa while coasting • Proposed solution: • Keep controller in serial mode • Run inputs to SBC IFM SBC Inputs

13. Single Board Computer • Responsibilities • Automated motor control • Vehicle subsystem communication

14. Vehicle Subsystem Communication • RS-485 • Battery Management • Maximum Power Point Tracking • USB • Human-Machine Interface

15. Vehicle Subsystem Communication • RS-485 • Battery Management • Maximum Power Point Tracking • USB • Human-Machine Interface

16. Vehicle Subsystem Communication • RS-485 • Battery Management • Maximum Power Point Tracking • USB • Human-Machine Interface

17. Discrete Motor Control • Speed control mode • Speed is represented by throttle pot voltage • Full voltage represents full speed • Braking is represented by regen pot voltage • Torque control mode • Difference in pot voltages determines motor phase current • Motor phase current is proportional to torque

18. Serial Motor Control • Values exist in registers on motor controller • SBC routines include • Cruise control • Regenerative braking control • Report motor condition to other subsystems • Respond to condition of other subsystems

19. Load Testing • Use motor-generator setup • Will provide • Verification of motor and cruise control functionality • Variable loading of motor

20. Diagram of Load Testing– Motor Setup • Previous test setup

21. Diagram of Load Testing– Generator • Generator • Added for load testing • Connected via shaft

22. Diagram of Load Testing– Load • Variable load • Mimic drive cycles

23. Current Status: Load Testing • With permission from Professor Habetler or Harley, we will conduct load testing in Van Leer Room W 139. • We will receive help from Stefan Grubic

24. Current Progress • Successful operation of Fall 2010 motor setup • SBC code restructuring and cleaning • Preliminary load test strategy • Preliminary air gap control system specs

25. Future Work • Successful compilation of SBC code • Select air gap adjustment motor • Serial control of motor • Write cruise control algorithm • Load and test motor • Regenerative braking algorithm/setup • Communicate with other subsystems

26. Questions