1. Point of Waveform Closure Sponsored by: Schweitzer Engineering Laboratories, Inc. Team Rush

2. Point of Waveform Closure Team Andrew King Scott Henderson Mentor: Normann Fischer (SEL) Advisors: Joe Law, Richard Wall Consultant: Jared Mraz Team Rush

3. Point of Waveform Closure Overview Purpose Need/Specs System Block Diagram Breakdown of Components Budget Plan/Schedule Priorities Team Rush

4. Point of Waveform Closure Team Rush What’s the point? Transformer failure is expensive

5. Point of Waveform Closure Team Rush Need Bank of power electronics switches Energize at any point in the voltage waveform Three phase capability

6. Point of Waveform Closure Team Rush Specifications Microprocessor Control Switches: withstand 400A peak Control three phases

7. Point of Waveform Closure Team Rush Specifications cont. Zero detection circuit System accuracy: within 500μs Track voltage/current waveform Budget not to exceed $3000.00

8. Point of Waveform Closure Team Rush Solution Versatile microprocessor based system Power electronics switches Voltage and current monitoring

9. Point of Waveform Closure Team Rush Solution cont. Modular for each phase –Less Risk –Ease of troubleshooting –More easily adaptable

10. Point of Waveform Closure Team Rush

11. Point of Waveform Closure Team Rush 0 Cross Detection Methods Explored: –Op-Amp Circuit –Comparator Circuit –Detection Through Software

12. Point of Waveform Closure Team Rush 0 Cross Detection Methods Explored: –Op-Amp Circuit Effective in Testing Accuracy within 100-200μs

13. Point of Waveform Closure Team Rush 0 Cross Detection Methods Explored: –Comparator Circuit Less complicated than op-amp circuit Accuracy reported to 1-2μs Will test in near future

14. Point of Waveform Closure Team Rush 0 Cross Detection Methods Explored: –Detection Through Software Could require significant processor resources Build capability into processor, explore at a later date

15. Point of Waveform Closure Team Rush Microprocessor Considered: –Rabbit –ARM –PSoC Best Choice: –PSoC

16. Point of Waveform Closure Team Rush Microprocessor PSoC –Capture and Compare –Flexible –Cheap Modularization Limited Risk Several available for experimentation

17. Point of Waveform Closure Team Rush PSoC Programmable System On Chip –Mfg. by Cypress Semiconductor –Mixed signal array 8-bit M8C microprocessor 24 MHz clock speed Analog and digital peripherals –Constructed based upon needs Building block architecture Programmed with C

18. Point of Waveform Closure Team Rush Switching Device Considered: –Triac –Thyristor(SCR) –SCR Modules Best Choice: –IXYS SCR Module MCC-220

19. Point of Waveform Closure Team Rush Switching Device IXYS SCR Module MCC-220 –Cheap –Back to back package –Easy to mount –Price: $136 each

20. Point of Waveform Closure Team Rush SCR Gate Driver Considered: –Enerpro –Applied Power Systems –Build it ourselves Best Choice: –Enerpro--Single Phase SCR Firing Board

21. Point of Waveform Closure Team Rush SCR Gate Driver Enerpro--Single Phase SCR Firing Board –Don’t have to build anything –Fires two SCRs –Possible source for 0 cross detection –Instantaneous Inhibit/Enable –Price: $269 each

22. Point of Waveform Closure Team Rush Heatsink Considered: –Purchase –Non-utilized heat sink belonging to the U of I Best Choice: –Non-utilized heat sink Slightly oversized but will work Price: Free

23. Point of Waveform Closure Team Rush Mechanical Contactor Cutler Hammer C25FNE350A –3 Pole 50A contactor –110-120V AC Coil –Price: appx. $200.00

24. Point of Waveform Closure Team Rush Current Measurement LEM HTFS 400-P/SP2 Isolated/Hall effect device Price: $47.00 each

25. Point of Waveform Closure Team Rush Voltage Measurement LEM CV 3-500 Closed loop voltage transducer Price: currently unknown, approx. $70.00

26. Point of Waveform Closure Team Rush PCBs Two per Phase –Board 1--Processor/0 cross detect –Board 2—Sensor/Sensor Support Price: Appx. $800

27. Point of Waveform Closure Team Rush Budget –Initial Budget$3000 SCRs(3)$408 SCR Driver Boards (3)$810 Contactor (1)$200 Microprocessors (3)$450 PCBs (6)$800 Current Transducers (3)$150 Voltage Measurement (3)$210 Miscellaneous Equipment$100 –Total$3128 –Amount Over Budget $128

28. Point of Waveform Closure Team Rush Plan/Schedule Remainder of First Semester –Order all purchasable components* –Work with loaner PSoC processor –Construct SCR/Driver/Contactor –Continue work on 0 cross detection

29. Point of Waveform Closure Team Rush Plan/Schedule Second Semester –Design/Build integrated PCBs –Integrate Microprocessor –Complete/Test entire system –Write paper for WCPRC

30. Point of Waveform Closure Team Rush Priorities (In order of importance) 1) Single phase switch 2) Priority 1—3 phase 3) Testing 4) Voltage/current monitoring 5) Residual flux measurement

31. Point of Waveform Closure Team Rush Any Questions? Andy King andrewking@vandals.uidaho.edu Scott Henderson scott.henderson@vandals.uidaho.edu http://seniordesign.engr.uidaho.edu/2007_2008/rush/