Web-based Interrogation

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Web-based Interrogation Control of a Power
QualityData Acquisition Device

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DESIGN TEAM
Glenn Wilson
Dr. Mark Halpin
Team Advisor
Team Leader Web Page Software Research Design
Jason Koberger True RMS meter Research
Design Hardware Testing Simulation
Melissa Wilson Documentation True RMS
meter Research, Design Simulation
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Motivation

• Need for improved data acquisition device for
  Southern Company
• Southern Company is our Co-op employer

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Problem

• Signal Information is not Readily Available
• Remotely
• Nonexistent
• On-site
• Must have computer available

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Approach

• On-site
• 4-Channel Voltmeter
• LCD Display Added
• Good/Bad Signal Indicator
• Button(s) to Cycle Through LCD Data

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Design Requirements

• Accuracy For voltage readings, the circuitry and
  display must begin reading at a minimum of 1 V
  and accurately read for low and high voltages.
  The RMS meter must also function as a true RMS
  meter.

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Design Requirements

• Temperature Circuitry must withstand 0? C
  minimum and 50? C maximum.

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Design Requirements

• Physical Packaging All design additions to the
  existing power quality device must be limited in
  size in order to fit in the existing box.

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Flow Diagram
Incoming Signal
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Flow Diagram
Input Signal
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Analytical Calculation
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Circuit 1
Meter Design from Electronic Design News
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Simulation Results
Vrms(actual) 148.49 V Percent Error 2.45
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Simulation Results
Vrms(actual)1.1 V Is this REALLY a true RMS
meter?
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Proof
Simulated value Vrms 0.77649 V
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Circuit 2
Maxim RMS circuit
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Accuracy Results
Vrms(actual) 0.7071 V Percent Error 0.15
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Accuracy Results
Vrms(actual) 148.49 V Percent Error 0.15
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Accuracy Results
Vrms(actual) 1.1 V Percent Error 0.18
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Temperature Results
All simulation values between 147.95 V and 148.64
V. Less than 1 error!!!
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Temperature Results
From 0º C to 50º C the error is lt1
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Physical Packaging Results
Component Quantity Dimensions(mm)
Varitronix Limited LCD Panel 1 94 x 24 x 4
Toggle Switch 1 Diameter 3.5 Height 29.5 (total) Height 3.5 (external)
LEDs 8 Diameter 1.8 Height 1.1
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Physical Packaging Results
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Conclusions

• Our circuit functions as a true RMS circuit.
• The true RMS circuit can accurately read low and
  high voltages, as well as non-sinusoidal
  waveforms.
• It operates properly throughout the required
  temperature range of 0º C to 50º C.
• All circuitry can conform to the existing device.

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Future Work

• Implement this circuit design in hardware form
• Add display circuitry and current reading
  functionality
• Implement remote interface

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Questions?
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References

• 1 Home Power Quality, http//energyoutlet.co
  m/res/powerqual/index.html, Energy Outlet, Iris
  Communications, Inc, USA, 1996.
• 2 R. C. Dugan, M. F. McGranaghan, and H. W.
  Beaty, Electrical Power Systems Quality,
  McGraw-Hill, New York, New York, USA, p. 1-3,
  1996.
• 3 W. M. Grady and A. H. Noyola, End User and
  Electric Utility Perspectives, Results of Power
  Quality Surveys in the United States, University
  of Texas at Austin, Austin, Texas, USA, 1995.
• 4 C. Peacock, Interfacing the PC,
  http//www.beyondlogic.org/serial/serial3.htm,
  USA, February 28, 2000.

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References

• 5 T. Cambra, Developing a Visual Basic
  Component for IIS/MTS, http//msdn.microsoft.com/
  workshop/server/components/vbmtsiis.asp,
  Microsoft Development Network, USA, June 19,
  1998.
• 6 D. Adair, J. Ball, and M. Pawlan, Trail 2D
  Graphics, http//web2.java.sun.com/
  docs/books/tutorial/2d/index.html, Sun
  Microsystems, USA.
• 7 P. Coleman and M. Halpin, Long Term
  Monitoring, 1999 Southeastern Meter School
  Conference, pp. 2-3, Birmingham, Alabama, USA,
  1999.
• 8 W. Berry, COM Objects and ASP,
  http//msdn.microsoft.com/workshop/server/
  asp/comtutorial.asp, Microsoft Development
  Network, USA, January 12, 1998.

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References

• 9 LCD Products, http//www.eio.com/lcdprodt.h
  tm, Electronics Information Online, USA, August
  23, 2000.
• 10 Newark Electronics http//www.newark.com,
  Newark Electronics, USA, 2000.
• 11 R. Moffat, ElectronicsCooling,
  http//www.electronics-cooling.com/Resources/ECArt
  icles/JAN97/jan97-01.htm, Stanford University,
  Stanford, California, USA, January 1997.
• 12 California Instruments Programmable AC
  Power Sources,
• http//www.ixpres.com/calinst/acpower.htm,
  California Instruments, San Diego, California,
  USA, September 2000.