Education Glenn A. Mottershead, P.E
University of Waterloo, Waterloo, Ontario
Professional Registrations Professional Experience
Mr. Mottershead has 31 years of experience in the engineering design, installation,
commissioning, testing, troubleshooting, and modernizing of large synchronous generators.
He is an expert in all aspects of high voltage epoxy mica bar and coil insulation systems,
including condition assessment, manufacturing systems, material development and all
relevant North American and International standards. He also specializes in the evaluation and testing of large generator stator cores and is currently chairing the IEEE Standard
Professional Affiliations
working group that is developing the P1719 Guide for Evaluating Stator Cores of AC
Electrical Machines Rated 1 MVA and Higher.
Prior to his recent position at HDR|DTA, Mr. Mottershead was a Senior Electrical Engineer
for a large hydroelectric equipment manufacturer where he was responsible for basic
electrical design and for numerous condition assessments, uprate studies, performance tests,
failure analysis and unit performance calculations to support large hydro generator
modernization projects. His design tasks included optimized high-voltage coil and bar
winding designs plus cores, wedging, circuit rings, field windings, and other related part designs for generator uprates and life extension. He also provided factory and process
Specialized Training and
engineering support for the manufacture of high voltage Epoxy VPI windings and the
Certifications
development and testing of new materials for improved dielectric performance. While in
this role, Mr. Mottershead was a member of the corporate Generator Technology Council,
Westinghouse Product Introduction Award for developing modern robust gradient
which planned technical policy for all the equipment manufacturer’s operating units
coating for field repair of damaged high-
worldwide and was a member of the corporate High Voltage Committee, which managed
voltage winding stress grading systems. He
insulation development and related issues.
experience in the testing and interpretation
Mr. Mottershead is an active participant for creation and maintenance of IEEE standards
of ELCID low energy core testing and high-voltage insulation partial discharge analysis
having worked on or chaired committees responsible for the content of IEEE standards 286,
434, 492, 522, 1415, 1434, 1553, 1719, ANSI C50.12 and C50.13 and was recently added to the Standards Council Of Canada's IEC TC2 committee as a synchronous machine expert for
Industry Tenure
reviewing applicability of international machine standards for Canada.
Mr. Mottershead’s first eight years of engineering experience were in the Generator Services Department of his employer’s Turbine and Generator Division where he worked in the field, installing and commissioning power plants.
Project Experience
LCHM McCormick Powerhouse Units 3, 4 and 5, Baie Comeau Quebec, 50 MVA to 70 MVA - Uprate and Modernization. Responsible for all aspects of the generator upgrade electrical engineering including data collection, condition assessment, DC ramp and PDA testing, upgrade study, winding and associated component design, field winding re- insulation process development, installation process writing, commissioning testing and finalizing of as built drawings. LCHM McCormick Powerhouse Units 6 and 7, Baie Comeau Quebec, 62.5 MVA to 80 MVA Uprate and Modernization - Responsible for the generator upgrade electrical engineering including data collection, condition assessment, core repair, upgrade study, winding and associated component design, and finalizing of as-built drawings. Exelon Conowingo Powerhouse Units 4,6,7, and 2, Conowingo PA, 40 MVA to 53 MVA Uprate and Modernization - Lead Engineer for the modernization and upgrade of four vertical generators having two different manufacturer’s designs. Project required multi-turn to bar conversions in new redesigned cores and stator frames with reinsulated field windings. Changing to bars required the coordination of multiple studies to verify the suitability of structures when changing the number of slots and winding parallels. Developed a novel bar braze connector design for improved field brazing quality. Pearblossom and Oso Pumphouse, California, 22,500, 11,600 and 4,000 Hp High-Speed Vertical Pump Motor Rewinds - Provided all electrical design and insulation development to replace original ashpaltic coils with epoxy mica form wound coils. Since the angle between top and bottom legs for the coil was very large, epoxy-based flexible knuckles needed to be developed to safely install the “hard” coil where heating the thermoplastic asphalt coil to provide flexibility was the original installation method. A new flexible knuckle approach was successfully developed, applied here and at many other high speed vertical and horizontal units since. Modernized winding and associate part design drawings for manufacture, dimensional data collection and or verification, installation instructions, factory and field test procedures and client technical correspondence was performed for the followings rewind projects: ■ Kananaskis, Transalta, 5.1 MVA (2007) ■ Mountain Chute, Ontario Power Gen, 75 MVA (2007) ■ Ashihik, Yukon Electric, 19.2 MVA (2006) ■ Chevron Texaco, Southern Cal. Edison, 24 MVA (2004) ■ Northfork, Portland General Electric, 24 MVA (2003) ■ Faraday, Portland General Electric, 24 MVA (2002) ■ Summer Falls, GCPHA, 48.7 MVA (2001) ■ Oak Grove, Portland General Electric, 30 MVA (2001) ■ Lemolo, PacifiCorp, 34.7 MVA (2000) ■ Burrard Steam Plant, BC Hydro, 180 MVA (2000) ■ Miranda Brazil, IMPSA Argentina, 136 MVA (2000) ■ Wharton GE Fr.7, Houston Light & Power, 57 MVA (1999) ■ Des Joachims, Ontario Hydro, 50 MVA (1999) ■ Lauderdale Turbo, Florida Light & Power, 43.2 MVA (1998) ■ Pelton, Portland General Electric, 50 MVA (1998) ■ PPL Brazil, IMPSA Argentina, 90 MVA (1998) ■ Lloyd Shoals, Georgia Power, 14.4 MVA (1997) ■ Otto Holden, Ontario Power Gen. 27 MVA (1997) ■ Fish Water, Us Army Corp., 13.8 MVA (1997) ■ Woodleaf, Oroville Wyandotte ID, 58 MVA (1997) ■ McKay, Great Lakes Power, 25 MVA (1996) ■ Grand Coulee Pump Motor, USBR, 49.4 MVA (1996) ■ Forbestown, Oroville Wyandotte ID, 46.6 MVA (1996) ■ Narrows, Pacific Gas & Electric, 55 MVA (1995) ■ Big Creek 3, Southern Cal. Edison, 35 MVA (1995) ■ Salt Springs, Pacific Gas & Electric, 30 MVA (1995) ■ Big Creek 1, Southern Cal. Edison, 28 MVA (1994) ■ Portal, Southern Cal. Edison, 10 MVA, (1994) ■ Big Creek 4, Southern Cal. Edison, 50 MVA (1993)
■ Andrews, Great Lakes Power, 9 MVA (1993) ■ Island Falls, Saskpower, 18 MVA (1992) ■ Black Eagle, Montana Power, 10.5 MVA (1991) ■ Chelsea, Hydro Quebec, 36 MVA (1990) In addition to the above complete rewind projects, a number of projects were supported where input was for assessments or sub-system designs only, e.g., replacement core, re- wedging, winding or core condition assessment, performance calculations and or troubleshooting. Examples of these projects follow: Uprate of Ross Dams, Seattle City Light - The Ross Dams are comprised of four 125 MVA units. The core and frame exhibited unusual behavior during full flux loop testing. The problem was studied, and core and frame frequency responses were measured and the core was found to be resonant in a zero mode which caused severe vibration amplitudes to occur during test excitation from loop test flux. The test that was intended to electrically stress interlaminar insulation was causing severe mechanical damage to frame welds and other components. It was demonstrated that careful ELCid testing would be more appropriate to determine interlaminar insulation quality in this case, and this was done successfully on three of the four units. Stator Core Condition Assessment, Robert Moses Hydroelectric Facility, New York Power Authority- The Robert Moses Hydroelectric Facility is comprised of thirteen 215 MVA units. Evaluation of the expected remaining life of cores continuously operated since the 1960s. The generator’s history review indicated they had endured air flow distribution problems for the majority of their service life. The core exhibited wide spread interlaminar insulation faults during full flux loop testing associated with original air flow pattern. Findings from study supported decision to replace the cores, showing repairs to existing core fault locations would not sufficiently reduce operational risks of future core faults. (2005) Upgrade of Summer Falls, Grand Coulee Project Hydroelectric Authority - The Summer Falls Project is two 48.7 MVA units. Responsible for designing a replacement core and bar winding in the original machine which suffered from high voltage degradation due to the overstressing of the original stator winding. Additional insulation was required to reduce the ground wall stress and to maintain the current unit rating which required a new, deeper slot design. The resulting deeper slot offset the space taken up with thicker insulation to allow equivalent copper cross sections. It also caused a decrease in back iron depth which then changed the mechanical frequency response of the core and increased the core flux density. Calculations were done to ensure the new arrangement would not introduce objectionable noise or vibration and the flux density and core yoke loss were acceptable. (2003) Generator Upgrade and Rehabilitation, Grant County, Wanapum Power Hydro Plant, Columbia River, Washington - Grant County PUD Wanapum is comprised of 10 units, each currently rated at 110 MVA, 13.8 kV, to be uprated to 128 MVA. Work for upgrading these 10 units is expected to include new frames, cores, stator windings and field windings. Mr. Mottershead is acting as owner’s engineer in review of the basic upgrade and details of the manufacturer’s design on this project, based on his experience as a design engineer for a major manufacturer. (Ongoing) Ludington Pump Storage Plant, Eastern Shores of Lake Michigan, Michigan - Ludington Pump Storage Plant contains 6 reversible units each rated 315 MVA at 20 kV, to be uprated to 455 MVA. The generator-motors in this plant have had a history of corona based problems associated with 20 kV stator windings operating in air. The Owners were specific in requesting Mr. Mottershead’s support for this very large re-habilitation project
because of his extensive experience in high voltage insulation, gradient system material development, application and design. (Ongoing) Helms Pumped Storage Plant, Board of Consultants, Pacific Gas & Electric, Fresno County, CA - Mr. Mottershead was named to the Technical Consulting Board to evaluate specific operational risks within the generator-motors. Helms Powerhouse is a three vertical unit underground facility that was commissioned on June 30, 1984. The plant has three Hitachi vertical, reversible pump-turbines each coupled to a Westinghouse generator-motor. The pump-turbine nameplate rating in the generating mode is 480,000 HP at 1,625 ft net head. The rating in the pumping mode is 2,400 cfs at a total head of 1,500 ft. The generator- motor nameplate rating is 390 MVA at 18 kV. (Ongoing) Cabin Creek, A & B Units, Xcel Energy - 166.7 MVA, Generator-Motor life extension and up-rate study. Cabin Creek pump storage plant operates 2 vertical generator-motor units originally manufactured in 1966. The units are designed to provide peaking and reserve generating capacity. The powerhouse is at an elevation of 10,018 feet above sea level. The two reversible pump-turbine generators operate at 13.8 kV and 360 RPM and have a combined rated generating capacity of 300MW at 1,190 ft net head. (Ongoing) Boundary Units 55 and 56, 210 MVA, Seattle City Light - Owner Engineer for major generator overhauls including managing core structural vibration issue. Boundary hydro power plant operates 6 vertical generators with the 2 largest units being scheduled for up-rate and life extension. The generators, rated at 14.4 kV, 128.6 RPM were originally manufactured in 1984. These units have suffered from severe core and frame resonant vibration since initial commissioning, vendor selection and redesign will be based on proven ability to manage problems of this nature. (Ongoing) Spray Unit 2, TransAlta - 60 MVA, Vertical generator manufactured in 1960, operating at 13.2 kV and 450 RPM. Problem – chronic recurring vibration at core split locations. Borescopic and visual inspection of core splits, core to frame attachments and other related areas leading to an understanding of the cause of core instability and recommendations for resolution. (2009) Upper Bonnington, Units 1 to 4, 7.5 and 7.0 MVA, FortisBC – Two unique aged designs of vertical generators originally manufactured in 1906 and 1914, operating at 2.3 kV and 180 RPM. Plant runs infrequently and required special redesign knowledge for capital budget planning to determine viability of continued operation. Objective is to increase generator operating voltage to 7.2 kV at minimal cost. (Ongoing) Rumford Falls, Unit 3, 10.9 MVA, Brookfield – one vertical generator originally manufactured in 1926 operating at 11 kV and 200 RPM. Perform a general condition assessment to determine the probability of re-using the generator stator core prior to dismantling and testing the core. Prepare generator major overhaul specification based on finding and recommendations. (2009)
■ Cascade Unit 2, TransAlta, 20 MVA, Condition assessment (2008) ■ Ludington, Consumers, 325 MVA, Motor/ Generator core damage diagnostics (2008) ■ Blue Mesa, USBR, 48 MVA, Condition assessment (2008) ■ Kemano, ALCAN, 122 MVA, Bar strand design and factory tooling design (2007) ■ Gorge, Seattle City Light, 66.7 MVA, Emergency lower cap replacement design and
■ Bonneville, U.S. Army Corp., 68 MVA, Stator winding design. (2007) ■ Horseshoe, Transalta, 2.5 MVA, Condition assessment (2006) ■ Ghost, Transalta, 15 MVA, Condition assessment (2006)
■ Ross, Seattle City Light, 125 MVA, Troubleshoot cooling air flow distribution problems
■ Ludington Pump Generating Units, Detroit Edison/ Consumers, 20 KV, 325 MVA
gradient system repairs, winding condition assessment (2005)
■ High Falls, Great Lakes Power, 28.7 MVA, Commissioning tests (2005) ■ New England Power, All Hydro Units, Due diligence (2005) ■ Robert Moses, NYPA, 215 MVA, Stator core ELCid and loop testing. (2005) ■ Ohio Falls, Louisville Gas & Electric, 17 MVA, Condition assessment, ELCid on Unit 6
■ Conowingo, Exelon, 62 MVA, Unit 8, troubleshooting high frequency core noise,
■ Beechwood, New Brunswick Power, 40 MVA, ELCid core testing (2005) ■ Chief Joseph, U.S. Army Corp., 100 MVA, Troubleshoot burning group jumpers (2004) ■ Hollingsworth, Great Lakes Power, 22.2 MVA, Condition assessment (2004) ■ Lewiston, NYPA, 25 MW, Post fire investigation and stator core ELCid (2004) ■ Bath County, Dominion, 447 MVA, 20 KV, Troubleshooting high voltage winding
testing, bar installation problems, and PDA on multiple units (2003)
■ Calderwood, Alcoa, 45 MVA, troubleshooting field pole fitting on replacement rotor rim
■ Muddy Run, Exelon, 111 MVA, Lower bar cap replacement (2003) ■ Minidoka, Idaho Power, 10 MVA, Novel loose field pole fix (2003) ■ Alamo, DWR, California, 18 MVA, Fire damage emergency repairs and core testing
■ Tillery, Carolina Power & Light, 27.5 MVA, Condition assessment (2002) ■ Blewett, Carolina Power & Light, 5 MVA, Condition assessment (2002) ■ Lower Bonnington, FortisBC, 24 MVA, Commissioning Tests (2001) ■ Hyatt, PG&E, 115 MVA, ELCid core testing (2001) ■ Outlet, Transalta, 12.5 MVA, Condition assessment (2000) ■ Lois, Powell River Energy, 21 MVA, Condition assessment and stator winding design.
■ South Slocan, FortisBC, 24 MVA, Commissioning Tests (1999) ■ Grand Coulee, USBR, 125 MVA, Replacement stator winding design (1998) ■ Wabush Synchronous Condensers, CFLCo, 60 MVA, Rewedge design, damper winding
and novel shorted field coil fix (1995, 1988, 1976)
■ Davis Dam, USBR, 45 MVA, Condition assessment and data collection. (1994) ■ Noxon, WWP, 126 MVA Commissioning testing, core repair (1994) ■ Sithe Energy, Brockville ON, 250 MVA PAC Plant, Offline PDA and condition
■ Dahurat, Morocco, 10 MVA, Commissioning tests (1992) ■ BEO, Morocco, 45 MVA, Commissioning tests (1992) ■ Little Long, Ontario Power Gen. 64 MVA, Replacement stator winding design (1989) ■ Elk Falls, Fletcher Challenge, 29.4 MVA Turbo Inspection and Test (1988) ■ Nanticoke, Ontario Hydro, 555 MVA, Turbo rotor rehabilitation process development
■ Trenton, Nova Scotia Power, 150 MVA, Turbo condition assessment (1983) ■ Palembang, PLN Indonesia, 21.5 MVA Gas Turbine Generator Performance testing
Selected Technical Papers and Standards
G. Mottershead, B. Paley, B. McNamara “Verification of the effectiveness of EL CID on a
hydrogenerator stator core” Hydrovision Conference July 1998
IEEE 286 - 2001, Recommended Practice for Measurement of Power Factor Tip-Up of Electrical
IEEE 434 - 2006, Guide for Functional Evaluation of Insulation Systems for AC Electric Machines
IEEE 492 - 1999, IEEE Guide for Operation and Maintenance of Hydro-Generators IEEE 522 - 2004, IEEE Guide for Testing Turn Insulation of Form-Wound Stator Coils for
IEEE 1415 - 2006 Guide for Induction Machinery Maintenance Testing and Failure Analysis. IEEE 1434 - 2000, Guide to the Measurement of Partial Discharges in Rotating Machinery IEEE 1553 - 2002, Trial-Use Standard for Voltage-Endurance Testing of Form-Wound Bars and Coils for Hydro-generators IEEE P1665 – Draft Guide for the Rewind of Generators 50 or 60 Hertz, 1 MVA and Higher IEEE P1719 - Draft Guide for Evaluating Stator Cores of AC Electric Machines Rated 1MVA and
ANSI/IEEE C50.12 - 2005, Standard for Salient-Pole 50 Hz and 60 Hz Synchronous Generators and
Generator/Motors for Hydraulic Turbine Applications Rated 5 MVA and Above (Vice-chair)
ANSI/IEEE C50.13 - 2005, Standard for Cylindrical Rotor 50 Hz and 60 Hz Synchronous Machines
Memorandum Traumatic Brain Injury and Other Brain Injury: Some Basic Facts and Possible Effects Epidemiology of TBI: Males are twice as likely to experience injury as females Second most affected group: age 75 or older Third most affected group: age 5 or younger Common Causes of TBI or Other Brain Injuries: (Can involve directs blow to the head or rapid acceleration and decelera
R e v i e w s / C o m m e n t a r i e s / A D A S t a t e m e n t s W O R K G R O U P Recommendations for Management of Diabetes During Ramadan ONIRA AL-AROUJ, MD OUSSAMA KHATIB, MD, PHD ADHIA BOUGUERRA, MD SUHAIL KISHAWI, MD OHN BUSE, MD, PHD BDULRAZZAQ AL-MADANI, MD HERIF HAFEZ, MD, FACP LY A. MISHAL, MD, FACP OHAMED HASSANEIN, FRCP ASOUD AL-MASKARI, MD, P
Education 
MVA Uprate and Modernization - Responsible for the generator upgrade electrical 
■ Andrews, Great Lakes Power, 9 MVA (1993) 
because of his extensive experience in high voltage insulation, gradient system material 
■ Ross, Seattle City Light, 125 MVA, Troubleshoot cooling air flow distribution problems
■ Ludington Pump Generating Units, Detroit Edison/ Consumers, 20 KV, 325 MVA
gradient system repairs, winding condition assessment (2005)
■ High Falls, Great Lakes Power, 28.7 MVA, Commissioning tests (2005) ■ New England Power, All Hydro Units, Due diligence (2005) ■ Robert Moses, NYPA, 215 MVA, Stator core ELCid and loop testing. (2005) ■ Ohio Falls, Louisville Gas & Electric, 17 MVA, Condition assessment, ELCid on Unit 6
■ Conowingo, Exelon, 62 MVA, Unit 8, troubleshooting high frequency core noise,
■ Beechwood, New Brunswick Power, 40 MVA, ELCid core testing (2005) ■ Chief Joseph, U.S. Army Corp., 100 MVA, Troubleshoot burning group jumpers (2004) ■ Hollingsworth, Great Lakes Power, 22.2 MVA, Condition assessment (2004) ■ Lewiston, NYPA, 25 MW, Post fire investigation and stator core ELCid (2004) ■ Bath County, Dominion, 447 MVA, 20 KV, Troubleshooting high voltage winding
testing, bar installation problems, and PDA on multiple units (2003)
■ Calderwood, Alcoa, 45 MVA, troubleshooting field pole fitting on replacement rotor rim
■ Muddy Run, Exelon, 111 MVA, Lower bar cap replacement (2003) ■ Minidoka, Idaho Power, 10 MVA, Novel loose field pole fix (2003) ■ Alamo, DWR, California, 18 MVA, Fire damage emergency repairs and core testing
■ Tillery, Carolina Power & Light, 27.5 MVA, Condition assessment (2002) ■ Blewett, Carolina Power & Light, 5 MVA, Condition assessment (2002) ■ Lower Bonnington, FortisBC, 24 MVA, Commissioning Tests (2001) ■ Hyatt, PG&E, 115 MVA, ELCid core testing (2001) ■ Outlet, Transalta, 12.5 MVA, Condition assessment (2000) ■ Lois, Powell River Energy, 21 MVA, Condition assessment and stator winding design.
■ South Slocan, FortisBC, 24 MVA, Commissioning Tests (1999) ■ Grand Coulee, USBR, 125 MVA, Replacement stator winding design (1998) ■ Wabush Synchronous Condensers, CFLCo, 60 MVA, Rewedge design, damper winding
and novel shorted field coil fix (1995, 1988, 1976)
■ Davis Dam, USBR, 45 MVA, Condition assessment and data collection. (1994) ■ Noxon, WWP, 126 MVA Commissioning testing, core repair (1994) ■ Sithe Energy, Brockville ON, 250 MVA PAC Plant, Offline PDA and condition
■ Dahurat, Morocco, 10 MVA, Commissioning tests (1992) ■ BEO, Morocco, 45 MVA, Commissioning tests (1992) ■ Little Long, Ontario Power Gen. 64 MVA, Replacement stator winding design (1989) ■ Elk Falls, Fletcher Challenge, 29.4 MVA Turbo Inspection and Test (1988) ■ Nanticoke, Ontario Hydro, 555 MVA, Turbo rotor rehabilitation process development
■ Trenton, Nova Scotia Power, 150 MVA, Turbo condition assessment (1983) ■ Palembang, PLN Indonesia, 21.5 MVA Gas Turbine Generator Performance testing
Selected Technical Papers and Standards 
IEEE 434 - 2006, Guide for Functional Evaluation of Insulation Systems for AC Electric Machines
IEEE 492 - 1999, IEEE Guide for Operation and Maintenance of Hydro-Generators IEEE 522 - 2004, IEEE Guide for Testing Turn Insulation of Form-Wound Stator Coils for
IEEE 1415 - 2006 Guide for Induction Machinery Maintenance Testing and Failure Analysis. IEEE 1434 - 2000, Guide to the Measurement of Partial Discharges in Rotating Machinery IEEE 1553 - 2002, Trial-Use Standard for Voltage-Endurance Testing of Form-Wound Bars and Coils for Hydro-generators IEEE P1665 – Draft Guide for the Rewind of Generators 50 or 60 Hertz, 1 MVA and Higher IEEE P1719 - Draft Guide for Evaluating Stator Cores of AC Electric Machines Rated 1MVA and
ANSI/IEEE C50.12 - 2005, Standard for Salient-Pole 50 Hz and 60 Hz Synchronous Generators and
Generator/Motors for Hydraulic Turbine Applications Rated 5 MVA and Above (Vice-chair)
ANSI/IEEE C50.13 - 2005, Standard for Cylindrical Rotor 50 Hz and 60 Hz Synchronous Machines