Initial Project Summary
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Note: Our first client interview was before our initial project summary was complete, so this was composed after having had an interview with the client. During the first part of our interview the client answered most of the questions we had.

Stakeholders
•    Sponsor: Normann Fischer and Schweitzer Engineering Laboratories, Inc.
•    Customer: Power engineers who test power transformers for faults.
•    Advisor: Joe Law
•    Design Team: Jared Mraz, Jacob Pomeranz, Eevi Maki
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Problem Statement
    Faults in transformers are usually found when it’s too late and the transformers are already ruined. This costs many companies (including power) lots of money. Testing is available in the lab, but it’s not practical. Some of the tests performed in the lab cannot be performed on site while the transformer is connected in its circuit and energized. If the transformer is connected to a large part of the power grid it cannot be shut down for testing at random times. Some transformers are too large to move to a lab for testing, anyway. Many large power transformers take years to build and have to be shipped at extreme expense via barge. These transformers are not replaced often.
    We want to find the limits of sensitivity when testing these inter turn winding faults. Can the fault be detected when it’s 1% of the windings? Can the fault can be detected when the transformer is energized without hurting the circuit the transformer is connected to or the transformer itself? These are just a few of the questions we want to answer. In the long run, power companies would have lower costs and consumers could have lower cost power.
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Questions
1.    Who is our main contact?
Normann Fischer
2.    How do we contact the client?
E-mail or phone
3.    Why is the client interested in this problem?
It’s an ongoing problem in the power industry, and SEL would like to work towards fixing it.
4.    Why is this such a problem?
It affects the entire power industry and costs an inordinate amount of money.
5.    What are the current transformer tests in the industry?
Oil test using a relay that detects air bubbles in the oil, but by the time, the transformer is tripped—it’s too late and transformer is ruined. Other tests need to be performed in a lab and it’s unrealistic to move large transformers.
6.    How well do they work?
Answered above.
7.    What is our initial goal?
Test power transformer to find sensitivity of inter-turn winding faults.
8.    What is our final goal?
Write a paper on our findings and present at power conference.
9.    What is an ultimate goal? (That may not be completed in this project.)
Have a method to test energized transformers in the field with no harm to tester.
10.    What are our specifications?
Listed on spec sheet.
11.    What should the transformer’s rating be?
25 kVA for core size and 50 kVA for wire.
12.    What are our constraints?
Listed in constraint section.
13.    What is the top priority right now?
•    Specifications for the transformer.
•    Ordering the transformer (takes 6-8 weeks to build).
14.    What should our focus be after that?
Work on building the test bench and testing the existing transformer.
15.    What specific training will we need?
See learning needs below.
16.    How should the test bench look?
Professional and well-labeled.
17.    What are the specifications for the test bench?
Listed with specs.
18.    What are the constraints for the test bench?
Listed with constraints.
19.    What other concerns should we be looking into?
A safe way to cause the short without ruining the transformer using fuses, circuit breakers, or switches. Also consider thermal analysis.
20.    When should we have this completed?
Transformer should be ordered to arrive ASAP. Initial testing can begin once transformer is ordered. Paper should be complete by March 2007.
21.    What is our budget for the transformer?
About $5,000.
22.    What is our budget for the project?
Besides the transformer cost, there will be about $3,000 for other supplies which will be requested from Normann as needed .
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Learning Needs
Technical
•    Transformer theory (brush up)
•    Transformer manufacturing (a bit)
•    3-phase power
•    Inter turn winding faults
•    Limits of inter turn winding sensitivity
•    Analyze collected data
•    Thermal analysis
•    Contactor

Specialized Design and Instrumentation
•    Relays
•    Labview
•    Current transformers
•    Thermocouples
•    Search coils

Interdisciplinary Topics
•    Creating test bench

Codes & Standards
•    IEEE C57.19-1995
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Preliminary Budget
ITEM COST
Current transformers
Controllers
Fuses
Circuit breakers
Material for test bench and testing
$3,000
Relay (provided) $0
Labview (UI has) $0
Graduate Student Support $0
Transformer $5,000
TOTAL $8,000
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Preliminary Schedule
DATE (S) DELIVERABLES & MEETINGS
Tuesdays at 4:45pm Client meeting
Thursdays at 3:30pm Team meeting
October 24, 2006 Web site review
November 3, 2006 Preliminary Design Review
December 1, 2006 Snapshot Day (Mid-semester review)
Interim Design Report
March 2007 Detailed Design Review
April 2007 Design Expo
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For problems or questions regarding this web site, contact eevicmaki@vandals.uidaho.edu
Last updated: 4/26/07.
University of Idaho, Moscow, Idaho.