It happens every year—the Fall Meetings of the Doble Client Committees—a “utilities only” private forum. This is where electric-utility engineers share experiences in an open environment and freely voice their concerns. Some attendees are staunch veterans of 10, 20, or more of these gatherings. Also in the crowd are new faces, who having replaced retiring veterans now seek out the wisdom of their peers.

No matter which company or geographic area is represented, all of the delegates are united by a single mission – to further the safe and efficient delivery of electric power. The latest Fall meeting was no exception: In October, over 250 electric engineers gathered in Vancouver, British Columbia, to continue on this “knowledge expedition.”

Doble Engineering thanks area utilities BC Hydro and BC Transmission Corporation for their active participation in the October event, which included a keynote by Bruce Ripley, Vice President of Engineering for BC Hydro, and a field trip to BC Hydro’s Stave Falls Generating Plant. Producing an average of 280 gigawatt hours of electricity per year—enough to serve about 28,000 households—the original plant was turned into an electric power learning center after being replaced in service by a new plant with more efficient turbines. The Doble Client community also had the benefit of participation by many engineers from BC Hydro and BC Transmission.

For the latest listing of the April 2005 Doble Client Conference presentations and schedule, go to: www.doble.com/general/eventdetail.php?id=157

Following are highlights of Client Committee Meetings:

Arresters, Capacitors and Cable Accessories (ACCA)

ACCA delegates were updated on the progress of several Committee projects.

Arrester tabulations in the works—Doble Engineering is developing an Arrester Tabulations document for release in 2005. Who will find these useful: MEU and M2H test set users, and M4000 users.

Coming soon in electronic formats:  Arrester Field Test Guide and the Reference Book on Cables and Accessories will soon be included in electronic format of the M4000 Insulation Analyzer User Guide.

Tutorial on topic drawing serious interest—A tutorial on  “Manufacturing and Testing of Surge Arresters” submitted by Steve Brewer of Ohio Brass was considered. The audience indicated serious interest in this topic. As there is no IEEE standard on these tests, this offering would be beneficial and provide useful guidance to the Client Community.

DGA poll results—Doble Engineering reported an increase in the last year in the frequency of dissolved gas analysis (DGA) performed on cable. The committee was polled on a question that appeared on the “Ask Doble” e-mail forum about performing DGA on 115 kV high pressure fluid-filled cables. Only four delegates had this type of cable of which only one performed DGA.

DGA results are based on the type of incipient fault; key gases formed are as follows:

• arcing causes production of acetylene
• high-temperature overheating causes ethylene
• overheating causes methane and ethane production
• hydrogen indicates partial discharge and moisture problems.

Careful analysis of DGA results is critical to guide maintenance.

Doble reported that one client had installed sample valves at the cable splices. DGA performed at these sample locations did reveal cables with high combustible gas levels. This information caused cables with the highest gas content to be inspected and repaired.

Questions on failures—Other ACCA discussions included questions and exchange on failures of Ohio Brass, type VN, surge arrester, MCOV 70kV, Voltage Rating 90kV, as well as failures of different Joslyn arresters.

Topics for Doble’s Boston conference—The ACCA Committee selected five topics for presentation at the 2005 Doble Client Conference in Boston. Three of these have since been confirmed by the presenters:

• “Maintenance Testing of Medium Voltage Cables,” Skip Hicks, Electrical Reliability Services, Inc.  Phoenix, AZ.
• “Capacitor Bank Failure: Investigation of 2 700 kVAR, 13.8 kV Bank Capacitor Failure in Service,” Jean-François Chrétien, MESAR, Ghislain Garant, Alcan, Long Pong, Doble Engineering
• “On-line Condition Monitoring of Gapless Metal Oxide Surge Arresters,” Stig Kyrkjeeide, Oddgeir Kvien, Vegard Larsen, TransiNor

Responses are still pending from other selected ACCA presentations.

Asset & Maintenance Management (AMM)

Arc Flash safety proposals—Discussions included an Equipment Health Rating (EHR) Program on Transformers, and two proposals on topics relating to safety in regards to Arc Flash. Florida Power & Light shared their latest knowledge with a presentation on Hurricane Preparedness.

Topics for Doble’s Boston conference—The AMM Committee selected a number of presentations that will be included in the upcoming 2005 Doble Client Conference. These include: 

• “Facilitating Essential Repairs to 400kV GIS substation through the Use of Temporary Overhead Line Bypass Arrangements,” Zac Richardson, National Grid Transco
• “Reliability Centered Maintenance Program at Grant County PUD,” Laurie Dayton, Grand County PUD
• “Reliability Centered Maintenance Program at NYPA,” John Troisi, New York Power Authority
• “Equipment Health Rating (EHR) Program on Transformers,” Mike Lau, BC Transmission Corporation

Additional AMM presentations were selected and confirmations from those presenters are pending.

Bushings, Insulators and Instrument Transformers (BIIT)

Discussions—The BIIT Committee discussed a variety of subjects, including Bushings problems and failures, Daytime Corona Testing of Insulators, and Gasket problems.

Tutorial for Doble’s Boston conference— A tutorial on Coupling Capacitor Voltage Transformers (CCVTs) has been under consideration and is tentatively scheduled to be included on Sunday afternoon, April 10, at the April 2005 Doble Client Conference agenda. Ritz and Trench are two of the companies expected to participate. For a preliminary outline of the CCVT Tutorial agenda, click here.

BIIT papers for Doble’s Boston conference—The BIIT Committee selected numerous papers for presentation at the 2005 Doble Client Conference. Here are a few examples:

• “Daytime Corona Testing of Insulators Using the DayCor Camera,” Dr. Pinhas Lindher, Ofil, Ltd.
• “ABB Type GOB Neutral Bushing Failures,” Richard Michaud, National Grid
• “A Review of Past Bushing Problems,” Eileen Duarte, Doble Engineering

Important reminder: ABB Service Advisory—Another topic planned in the April 2005 BIIT session is a presentation by ABB regarding a past Service Advisory on ABB Bushing Types O Plus C, EEMAC/CSA, and T, with Ratings of 15 kV through 69 kV, 1200 Amps and under. While the Service Advisory was originally issued in 1998, ABB feels that utilities should be reminded of the Advisory, and the proposed course of action, in order to prevent bushing failures. For further details on the ABB Advisory, click here.

Circuit Breakers (CB)

The Circuit Breaker Committee met with close to 100 persons in attendance. Of prime importance were several safety related topics concerned with very serious arc flash issues, SF6 fault byproduct handling, and some shock issues in circuit breaker cabinets where DC terminals are not covered with a safety cover. The Committee considered some ideas for rewriting the Circuit Breaker Field Test Guide. They were updated on IEEE Switchgear committee work related to transformer failures caused by traveling waves originating in the arc of circuit breaker interruptions. Work on TRV determination and changes to standards were also noted.

On the maintenance side, the clients considered the issues of the correct overhaul intervals for breakers and disconnect switches. Problems with SF6 gas from manufacturers, SF6 leaks to atmosphere, and SF6 usage monitoring systems were discussed and experiences traded. New work in the use of byproducts in SF6 gas to diagnose issues within SF6 switchgear were presented. The testing of vacuum bottles in low voltage breakers was discussed. The agenda included discussion of 500 kV air blast breaker failures, SF6 high voltage interrupter failures and operating mechanism problems, as well as several issues with circuit switchers. The meeting closed with an open forum where new subjects such as important new failures of breakers and other switchgear were presented that had not been covered in the other discussions.

Topics for Doble’s Boston conference—The following three presentations have been confirmed for the April Client Conference:
 

• “Handling of SF6 Containers,” Bob Mueller, Airgas
• “Handling of SF6,” Lukas Rothlisberger, Dilo
• “Inspection, Maintenance, and Rebuilding Options for Older Circuit-Switchers,”  David Myers, John Hilgenkamp, S&C Electric Company

 Insulating Materials (IM)

Committee projects—A variety of Committee projects were discussed, including an update to the Insulating Fluids Reference Guide, a Gasket Material Selection Guide for Different Fluids, Insulating Materials Identification Guide, and work on an IEEE Gas Guide regarding DGA.

Nine proposed presentations were reviewed by the group, all of which received a high level of interest. A tutorial was suggested for consideration, “Eliminating hazards with pumping oil containing combustible gases.”

Oil Committee

Oil survey results—The "Doble Oil Survey," a survey of electrical insulating oils available on the market, was reviewed for 2004 results. "Stray Gassing," which is the gassing behavior of new oils at low temperatures, was discussed and drew interest.

New research—A concern has been raised about corrosive sulfur in transformer oils that goes undetected in traditional tests. The Oil Committee has performed new research on this topic and expects a presentation possibly as early as the 2005 Doble Conference.

Protection Apparatus Test (PAT)

PTUG collaboration—The PAT Committee meeting was able to benefit from attendance of the ProTesT User Group (PTUG) members. PAT’s main focus will continue to be held at Doble’s Fall event, as this has the largest number of Protection-related attendees. PAT will work closely with PTUG planners to design a program to be held in conjunction with the Fall PTUG and Fall Client Committee Meetings.

Going forward, the PAT committee will hold a committee meeting at the Spring Conference, and may offer presentations as part of the Spring Conference, in conjunction with another Client Committee.

Rotating Machinery (RM)

Proposals for Doble’s Boston conference—Eleven proposals were voted as having high interest for presentation at the 2005 Client Conference. These included a high-voltage insulating system, the impact of recent IEEE standards on new windings purchases, a hydroelectric generator exciter replacement program, and problems with turbine lubrication oils used at hydroelectric plants. Of the accepted RM presentations, Doble has received confirmation on the following:

• “Rehabilitation at Crystal Power Plant,  U.S. Bureau of Reclamation
• “System stability and Black Start Capability,” U.S. Bureau of Reclamation. This paper will discuss the new requirements to demonstrate black start.
• “Impact of Recent IEEE Stator Insulation Standards on Buying New Windings,” Greg Stone, Iris Power Engineering. Iris will also present “Trends in Stator Winding Partial Discharge Activity on Modern air-cooled Motors and Generators.”
• “Hydroelectric generator exciter replacement program at several U.S. Army Corps of Engineer sites,” Steven Tanner, U.S. Army Corps of Engineers
• “Problems with Turbine Lubrication Oils Used at Hydroelectric Powerplants,” John Micetic, US Army Corps of Engineers
• "Visual Inspections," a presentation sponsored by the RM Committee, on Tuesday, April 12.

Transformers

The Transformers Committee meeting was well attended to review the extensive selection of proposed presentations. Topics of interest included: Electromagnetic Interference (EMI) Diagnostics of Power Transformers, and Test Result Analysis. Sweep Frequency Response Analysis (SFRA) remains of interest to the group, as the methodology continues to be developed and refined. A presentation highlight will be the application of the SFRA test equipment to perform transformer turns ratio measurements.

One client shared an experience with a 115kV, 13.2kV, 40MVA, core form transformer with high Ch power factor obtained during acceptance testing. The experience highlighted the value of the enhanced voltage factory testing and field testing. The client advised that the levels of partial discharge allowed during the enhanced voltage test should be included in the IEEE document or in the company’s specifications. Also, the customer specification needs to be clear concerning what factory test failures need to be reported.

Proposals for Doble’s Boston conference—The Spring 2005 Transformers session agenda is expected to be jam-packed with relevant presentations and discussions. Here is a brief selection of just a few of the confirmed subjects:

•  “Client Case Study: Advanced Diagnostics Support Critical Decision Making,” Richard K. Ladroga, Doble Engineering
• “Field Experience with the Implementation of a New On-Line Vibro-Acoustic Diagnostic for On-Line Tap Changers”, Claude Rajotte, Hydro-Quebec
• Presentations on Swept Frequency Response Analysis (SFRA) by Tony McGrail and Charles Sweetser, Doble Engineering
•  “FRA Equipment Used to Perform Percent Impedance and TTR Testing”, Servando Sánchez, Substations Department Comisión Federal de Electricidad Morelia , Mich. , MEXICO; Alberto Avalos, Graduate Dept. Universidad Michoacana de San Nicolás de Hidalgo Morelia, Mich., MEXICO

Other Activities in Vancouver: ProTesT User Group Meeting (PTUG)

One-on-one clinic—A PTUG clinic kicked off the week, enabling PTUG members to get one-on-one assistance with software questions. This was followed by two full days of technical presentations by Clients, Doble Engineering, and outside presenters.

Program discussions—A PTUG “Steering Committee” meeting was held on Wednesday morning. This included very active discussions on the desired direction for future PTUG events. Delegates expressed interest in future PTUG programs to include two separate tracks: an “Introduction to ProTesT” for beginner training and presentations and “Advanced” track for experienced users. This program would justify multiple delegates from PTUG user companies, and would continue to educate new Protection personnel, while expanding the knowledge of other delegates. Vancouver PTUG delegates also expressed a desire for the PTUG event to be a “Protection” Users Group, and not exclusively ProTesT-related.

PTUG cheerleading—Two representatives from the "Australasian Protection Users Group" shared their own event organization process. This is a group that encompasses Protection Users Groups in both Australia and Asia. Their North American colleagues especially liked the concept of having utility client representatives share the work to solicit presentations from colleagues. It was proposed that the North American PTUG follow the Australasian process, and pinpoint client representatives with whom to work together in order to plan the 2005 agenda. These individuals would be the key contact/cheerleaders within their company regarding the Doble PTUG. Note: If you have interest in being your region’s PTUG organizer, please send a message to lcolby@doble.com

Client Committee—The PAT Client Committee held its meeting in conjunction with the PTUG while in Vancouver.

Training—PTUG Training Sessions on Thursday and Friday were well-attended and delegates found them to be beneficial. Topics included "Introduction to ProTest, "Advanced Macros," "Introduction to ProTesT, "ProTesT Settings, and "Transducers and Meter Testing."

Evening events—The Vancouver events provided many opportunities for delegates to network in a relaxed manner. Evening receptions were held in the Doble product room the first three evenings; on Wednesday evening, a “Casino Night” was offered for some welcome fun and games.

"Best of" rating—Many clients rated this event to be the best “Doble Fall Meetings” in years. Praise-earning factors mentioned were the hotel and city, schedule of events, and technical content of the meetings. The Westin Bayshore Hotel was indeed a wonderful site, located on the edge of the city’s beautiful Stanley Park. Delegates experienced both the legendary Vancouver rainy weather, as well as gorgeous blue skis and fall colors.

Mark your calendars —The 2005 Fall Meetings of the Doble Client Committees and the ProTesT/Protection User Group Meeting will be held September 25-30, 2005 at the Grand America Hotel in Salt Lake City, Utah. For more information on the Doble Client Committees, click here.  

©2005 Doble Engineering Company All Rights Reserved.

If you would like more information about Doble products and services, please send an email to dobleinfo@doble.com