Transcript Web-based Interrogation of a Power Quality Data Acquisition Device

Web-based Interrogation
of a Power Quality
Data Acquisition Device
DESIGN TEAM:
Dr. Mark Halpin
Team Advisor
Jason Koberger
Glenn Wilson
Debugger
Web Page
Software Research
& Design
Melissa Wilson
True RMS meter
Research & Design
Team Leader
Hardware Testing
& Simulation
True RMS meter
Research, Design &
Simulation
Problem
• Signal Information is not Readily Available
– Remotely
• Nonexistent
– On-site
• Must have computer available
Circuit
Flow Diagram
Incoming
Signal
Squared
Integrated over
1 period
Square Root
RMS Output
Signal
Hardware Design Constraint
For voltage readings, the circuitry and display
must begin reading at a minimum of 1 Volt
and be accurate to ± 1 Volt. Also, the
voltmeter must act as a True RMS
voltmeter.
Accuracy Results
Closer
at the
Results for
VrmsLook
Values
forWorst
a Generated
60the
Hz60
Hz Sine Wave Input
Sine Wave
200
Actual
Vrms
150
110
Vrms from
Circuit
Vrms
Vrms
115
100
105
Worst
deviation
from actual
value
50
0
100
0
280
100
290 200
300300
Vpk-pk
Vpk-pk
400
310
500
320
Actual
Actual
Vrms
RMSfrom
+1V
Vrms
Circuit
Actual
RMS
Minus 1V
Accuracy Results
Vrms Values
a Generated
Triangle
Closer
Look for
at the
Worst Results
for
Wave Wave Input
the 60 Hz Triangle
Actual
Vrms
140
99
97
100
95
80
93
60
91
89
40
87
20
85
Vrms
Vrms
120
0
300
0
Vrms
from
Actual
Circuit
Worst
deviation
from actual
value
Vrms
Actual
Vrms
from
Vrms
+1
our circuit
310 200320 300 330 400 340500
Vpk-pk
Vpk-pk
100
Volt
Actual
Vrms
Minus
1Volt
Hardware Design Constraint
The circuitry should be able to operate
correctly within the ranges of 0° C to 50° C
(32° F to 122° F).
Temperature Constraints
Vrms
Vrms
Closer
Worst
Section
of with
Results
Plot
of Look
Vrms at
forthe
a 60
Hz sine
wave
the
temperature increased to 50 C
20
160
140
15
120
100
10
80
60
5
40
20
0
0
0
Actual Vrms
from
oscilloscope
Actual
Vrmsvalues
from
from
our circuit
oscilloscope
Actual value
Values
from
plus 1 Volt
our circuit
Worst
deviation
from actual
value
0
20
100 200
40
300
Vpk-pk
Vpk-pk
400
Actual Value
minus 1 Volt
60
500
Hardware Design Constraint
The cost of hardware additions to the
existing power quality device must be kept
below $50.00.
Cost Comparison
8 to 1 Multiplexer
RMS Converter
LCD Screen
Voltage Source
A/D Converter
9V Battery
Misc. Parts
$3.28
$12.25
$6.80
$2.58
$9.18
$1.50
$4.00
Maximum Cost:
$50.00
Prototype Cost:
$39.59
20% below cost
constraint
Software Design Constraint
The web interface must be compatible with
the latest versions of both Microsoft
Internet Explorer and Netscape Navigator.
Web Browser Compatibility
Software Design Constraint
The server side web code must be
executable via Windows NT Internet
Information Server.
Hardware/Web Status
Future Work
• Implement 8-1 Mux to allow switching
between 8 ports on the box
• Implement Indicator lights for each port
• Test the update rate of the RMS circuitry
and LCD screen
• Package Hardware
• Perform Real-Time testing on software
Questions?
References
[1] “Home Power Quality,” http://energyoutlet.com/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.
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.
References
[9] “LCD Products,” http://www.eio.com/lcdprodt.htm, Electronics
Information Online, USA, August 23, 2000.
[10] “Newark Electronics” http://www.newark.com, Newark Electronics,
USA, 2000.
[11] R. Moffat, “ElectronicsCooling”, http://www.electronicscooling.com/Resources/ECArticles/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.