1. HydroFly: Flywheel Gavin Abo Nate Stout Nathan Thomas

2. Background The flywheel is a mechanical energy storage device –Once up to speed very little energy is required to maintain desired speed Small draw on AMPS

3. Background Continued Flywheels were used during the industrial revolution to smooth out torque pulses in mechanical systems –We will use it in a similar fashion to smooth out voltage sags on the AMPS

4. Voltage Sags Drop in RMS voltage –Typically last from 1/2 cycle to a minute –Caused by actions on the system that have large current draws Motors starting Transformers energizing Pulsed load switching Electrical faults

5. Why Sags Are Bad Voltage sags have adverse affects on sensitive loads –Sags can cause loads to shutdown Loss of use Loss of Data Loss of production time

6. Navy Survivability of Naval ships in battle situations –In battle situations voltage sags can occur due to various reasons, causing critical systems to go offline Flywheel voltage sag detection devices could be used to help protect these critical systems

7. Education The flywheel energy storage system may be implemented into future power classes at the University of Idaho for educational purposes –Power quality classes –System protection classes –Transient analysis classes

8. Main Objective Implement the design by Satish Samineni –Be able to correct for up to 33% voltage sags on AMPS

9. We will focus on –Induction motor controller –Programming of the DC link –Synchronizing to AMPS –Protection circuitry We will not do: –Design of DC link –Design of Induction motor controller

10. Block Diagram

11. Switching

12. PWM A triangle wave reference is applied to a signal –Compared –Triangle high: logic 0 –Signal high: logic 1 –Applied to all 3 phases

13. Block Diagram

14. Series Transformer Diagram

15. Synchronization & Protection Use a phase lock loop to monitor and regulate phase Add any additional protection needed

16. In phase Out of phase

17. Budget *Shared costs between the two groups

18. Time Schedule

19. Questions? www.ece.uidaho.edu/hydrofly