technology and reliability improvements in ge’s...
TRANSCRIPT
Technology and Reliability Improvements
in GE’s 1.5MW Wind Turbine Fleet
James R. MaughanGeneral Manager
Product Service and WarrantyGE Wind Energy
September 17, 2007
Wind Turbine Reliability WorkshopSandia National LabsAlbuquerque, NM
p. 2James Maughan, GE Wind Wind Turbine Reliability Workshop
GE’s Infrastructure Businesses
GE and GE Wind
Oil & GasWater Aircraft Engines
RailEnergy Financial Services
Wind
Solar
Biomass
Hydrogen
- Nuclear
- Thermal
- Renewables
p. 3James Maughan, GE Wind Wind Turbine Reliability Workshop
• Formed May 2002…Purchased from Enron
• Foresee significant long term, global demand for Wind Turbines
• Continue growth with…
Technology - integrate with GE to improve on starting point…reliability, capacity factor, cost
Supply Chain – more turbines, with predictability
Permitting & Transmission – more turbine locations
Policy - support Long-term commitment
• Ecomagination
GE Energy’s Start in Wind Power
“Green is Green”…For Everyone
p. 4James Maughan, GE Wind Wind Turbine Reliability Workshop
GE Wind Growth and Investment
GE Wind since 2002:
$600MM+ technology investment …
• Unit production: 400 to 2500+
• Key suppliers: up 3x
• 2007 Revenue: $4.5B+
• Fleet size: 2000 to 8000
•Continued within 2-3 years …
• Expect policy issues to stabilize
• Continue to grow supply chain
• Expand capacity
• Becoming GE’s largest Energy product business
(units/yr)
• Managing supply chain …integrated with global suppliers
• Operational differentiation …driving dependable fulfillment
• Advancing technology …efficiency, reliability, diagnostics
‘07‘02
2,500+
~400
Accelerating global deployment
It All Depends on Reliability
p. 5James Maughan, GE Wind Wind Turbine Reliability Workshop
Why Reliable Operation is Everything
Customer View
• Price + Capacity Factor + Availability + Operating Costs = Customer Rate of Return
• Reliability issues directly cut production
• Reliability issues increase operating costs
• Reliability issues are aggravating
Reliability and Availability
• Reliability…component focused
- Failure rates, MTBF, MTBT, starting reliability, etc
• Availability…operator focused
- Fraction of time system is able to operate as intended
- Includes impact of failure on operation
- Failure rates, faults, outage length, planned repair, maintenance, etc
- Ties to lost production, lost revenue
The Fuel is Free. The Turbine Needs To Run.
p. 6James Maughan, GE Wind Wind Turbine Reliability Workshop
1.5sle Availability Summary - Customer Fleet View
2007
2005
0%10%
20%30%
40%50%
60%70%
80%90%
100%
0 0.2 0.4 0.6 0.8 1Availability
0 0.2 0.4 0.6 0.8 1
Per
cent
of F
leet
Engineering Availability
• Includes downtime for any reason (except grid outages)• Duration from coming off-line to return to service• Faults, repairs, maintenance, upgrades, etc
• Lost production calculated from wind speeds during downtime
p. 7James Maughan, GE Wind Wind Turbine Reliability Workshop
0
500
1000
1500
2000
0-1 h 1-4 h 4-24 h 1-4 d > 4 d
Fau
lt C
ou
nt
0
500
1000
1500
2000
2500
Fau
lt D
ow
nti
me,
hrs
# EventsDowntime
Availability Analysis By Fault Count and Duration
System Faults Component Failures
•More frequent but shorter events from system, thermal, integration, and operation issues
- impact is primarily lost production
•Less frequent but longer events from component failures
- impact is lost production andcost of component
p. 8James Maughan, GE Wind Wind Turbine Reliability Workshop
Fleet Relative Cost of Component Failure
•Lost Production and replacement cost data
•Failure data and predictions for continuous product improvement
Failure Data - Weibull Predictions
100.00 100000.001000.00 10000.00
0.01
0.05
0.10
0.50
1.00
5.00
10.00
50.00
90.00
99.00
0.01
0.5
0.6
0.7
0.8
0.9
1.0
1.2
1.4
1.6
2.0
3.0
6.0
β
Unr
elia
bilit
y, F
(t)
100.00 100000.001000.00 10000.00
0.01
0.05
0.10
0.50
1.00
5.00
10.00
50.00
90.00
99.00
0.01
0.5
0.6
0.7
0.8
0.9
1.0
1.2
1.4
1.6
2.0
3.0
6.0
β
Cycles100.00 100000.001000.00 10000.00
0.01
0.05
0.10
0.50
1.00
5.00
10.00
50.00
90.00
99.00
0.01
0.5
0.6
0.7
0.8
0.9
1.0
1.2
1.4
1.6
2.0
3.0
6.0
β
Unr
elia
bilit
y, F
(t)
100.00 100000.001000.00 10000.00
0.01
0.05
0.10
0.50
1.00
5.00
10.00
50.00
90.00
99.00
0.01
0.5
0.6
0.7
0.8
0.9
1.0
1.2
1.4
1.6
2.0
3.0
6.0
β
Cycles
p. 9James Maughan, GE Wind Wind Turbine Reliability Workshop
Typical Failure Root Cause Analysis Process
Slip Ring
Above rated pitch motor currents- (Temperature/Wear)
Protection devices CB for slip ring 400 V, 50 A
WTG SystemDesign
Maintenance Other
Humidity
Temperature.
Assembly error Slip Ring Assembly
Lightning Strikes
BAA Faults
Old Style to new style transition in design
Mechanical Wear of Brushes
Inadequate Brush Replacement
Slip ring cleaning procedures.
Slip Ring Lubrication procedures
EliminatedRoot Cause Contributor
Bearing Friction
Mechanical Wear of gold coating on slip ring.
Slip Ring
Above rated pitch motor currents- (Temperature/Wear)
Protection devices CB for slip ring 400 V, 50 A
WTG SystemDesign
Maintenance Other
Humidity
Temperature.
Assembly error Slip Ring Assembly
Lightning Strikes
BAA Faults
Old Style to new style transition in design
Mechanical Wear of Brushes
Inadequate Brush Replacement
Slip ring cleaning procedures.
Slip Ring Lubrication procedures
EliminatedRoot Cause Contributor
Bearing Friction
Mechanical Wear of gold coating on slip ring.
RCA Fishbone, Identification, Validation
Annual energy
production per w ind bin (kWh)
Annual number of
revolutions
Probability per w ind
bin
Annual energy
production per w ind bin (kWh)
Annual num ber of
revolutions
Probability per w ind
bin
Annual energy
production per w ind bin (kWh)
Annual num ber of revolutions
Probability per w ind
bin
Avg w indspeed (m /s) >>>
7.5 7.5 7.5 8.5 8.5 8.5 10 10 10
8.463 8.463 8.463 9.591 9.591 9.59 11.284 11.284 11.2841 0 0 0.03 0 0 0.02 0 0 0.0162 0 0 0.05 0 0 0.04 0 0 0.0303 0 437,410 0.07 0 350,384 0.06 0 260,294 0.0444 33,552 529,028 0.09 27,462 433,008 0.07 20,835 328,517 0.0555 112,715 604,015 0.10 94,850 508,278 0.08 73,935 396,202 0.0646 221,454 712,198 0.10 192,774 619,961 0.09 155,321 499,511 0.0717 358,705 807,086 0.10 325,002 731,254 0.09 272,299 612,672 0.0758 511,763 839,611 0.09 485,599 796,685 0.09 425,625 698,290 0.0769 655,944 775,207 0.08 655,858 775,105 0.08 605,008 715,009 0.075
10 714,918 668,306 0.07 757,894 708,480 0.07 740,242 691,979 0.07211 675,418 548,684 0.06 763,851 620,523 0.06 794,694 645,579 0.06712 565,133 434,475 0.04 686,033 527,424 0.05 764,846 588,016 0.06113 445,726 332,263 0.03 584,380 435,622 0.05 702,385 523,587 0.05414 332,432 245,653 0.03 473,629 349,991 0.04 617,419 456,246 0.04715 238,760 175,728 0.02 371,946 273,753 0.03 529,049 389,380 0.04016 165,366 121,709 0.01 283,414 208,593 0.02 442,511 325,688 0.03417 110,951 81,660 0.01 210,494 154,923 0.02 362,944 267,126 0.02818 72,146 53,099 0.01 152,449 112,203 0.01 292,036 214,938 0.022
Material Analysis
AnalyticsFailure Analysis
p. 10James Maughan, GE Wind Wind Turbine Reliability Workshop
0
500
1000
1500
2000
0-1 h 1-4 h 4-24 h 1-4 d > 4 d
Fau
lt C
ou
nt
0
500
1000
1500
2000
2500
Fau
lt D
ow
nti
me,
hrs
# EventsDowntime
Availability Analysis By Fault Count and Duration
System Faults Component Failures
•More frequent but shorter events from system, thermal, integration, and operation issues
- impact is primarily lost production
•Less frequent but longer events from component failures
- impact is lost production andcost of component
p. 11James Maughan, GE Wind Wind Turbine Reliability Workshop
Availability Analysis by Return to Service Process Step
Return to Service Process Steps
1. Identification, remote diagnostics, waiting period (if required)
2. Assemble needed teams, tools, and parts
3. Repair time
0
50
1000
1500
2000
2500
3000
Fau
lt H
andl
ing
/ M
anda
tory
Wai
t
Pen
ding
Rep
air
In R
epai
r
Pla
nned
M
aint
enan
ce
Un
avai
lab
ility
(h
ou
rs)
Pla
nned
Rep
air0
Un
avai
lab
ility
(h
ou
rs)
p. 12
James M
aughan, G
E W
ind
Wind Turbine Relia
bility W
orksh
op
Typ
ical Fault A
nd Ava
ilability D
ata
0 50
100
150
200
250
300
Blade angle asymmetry
Battery charging voltage
Planned repair
Rotor CCU fault voltage
Program start PLC
Rotor CCU collective faults
Pitch thyristor 1 fault
Cabinet Over temperature
Motor protection
Main switch released
Rotor CCU fault current
Planned Maintenance
Gearbox oil pressure
Weather downtime
Yaw runaway
Unavailability (hrs)
Cabinet Over temperature
0 30 60 90
120
150
180
Lost Production, MWhr
Blade angle asymmetry
Battery charging voltage
Planned repair
Rotor CCU fault voltage
Program start PLC
Rotor CCU collective faults
Pitch thyristor 1 fault
Motor protection
Main switch released
Rotor CCU fault current
Planned Maintenance
Gearbox oil pressure
Weather downtime
Yaw runaway
•Lo
st productio
n guides te
chnica
l effo
rt, field
solutio
ns, co
mponent re
desig
n, sy
stem im
provement
Unavaila
bility
Lost P
roductio
n
p. 13James Maughan, GE Wind Wind Turbine Reliability Workshop
Wind Turbine Blade Angle Asymmetry
Background
• Electronic pitch control system sets blade angle during high load wind control
• Under some conditions on some units, one blade lags behind, unit shuts down
Motor
Gear box
Drive gear
Bearing
Electronic Control
Motor
Gear box
Drive gear
Bearing
Electronic Control
p. 14James Maughan, GE Wind Wind Turbine Reliability Workshop
Anatomy of a Blade Angle Asymmetry Fault
0
2
4
6
8
10
12
14
16
18
20
200 250 300 350 400 450 500
Time [sec]
Bla
de
An
gle
, deg
Blade Angle 1 - Actual
Blade Angle 2 - Actual
Blade Angle 3 - Actual
Blade Angle Setpoint
2. Blade 3 begins to lag behind
3. Unit shuts down due to potential asymmetric loads
4. Blades return to feathered position on grid or battery power. Unit restarts.
1. Blades all following setpoint
p. 15James Maughan, GE Wind Wind Turbine Reliability Workshop
BAA - Root Cause Analysis
0
10
20
RMS Torque, Nm
Fre
quen
cy
Torque Capability
Bearing Torque Characteristics
Bearing Torque Data Summary
Revised Torque Capability
Root Cause Analysis• Variability in torque requirements
not seen in prototype data• ~4% of bearings outliers• Cause of variation not definitively
identified
System Solution• Torque applied to bearing
increased with use of higher ratio gearbox
• Loads, lifing, response time all validated
Possible Corrective Action• Uprate pitch gearbox • Avg 87% reduction in impact
validated
Pitch System Gearbox
Outliers
p. 16James Maughan, GE Wind Wind Turbine Reliability Workshop
Cabinet Over Temperature Faults
Background
• Energy dissipated in pitch motors and hub increases cabinet temperatures
• Temperature protection shuts down unit if necessary…
• … in some cases below spec of 40C outside ambient
Impact
0
5
10
15
20
25
30
FW01 FW10 FW19 FW28 FW37 FW46
Lo
st P
rod
uct
ion
, MW
hrs
Hub Axis Cabinet (3)
Hub Battery Cabinets (3)
Hub Center Cabinet Top Box
Hub Axis Cabinet (3)
Hub Battery Cabinets (3)
p. 17James Maughan, GE Wind Wind Turbine Reliability Workshop
Hub Ventilation Schematic
Ambient Air
Screen and deflector
Center
Cabinet
Flexible hose
exhaust
Root Cause Analysis
• Vendor cabinets tightly sealed
• Hub is stagnant and unventilated
• Internal hub temperature can peak higher than ambient
Possible Corrective Action
• Create consistent air flow through hub with vent
• Screen and deflectors to limit water, snow, debris, etc
p. 18James Maughan, GE Wind Wind Turbine Reliability Workshop
Typical Hub Temperature Data With Ventilation
0
5
10
15
20
25
30
35
40
45
50
4-Mar-07 5-Mar-07 6-Mar-07 7-Mar-07 8-Mar-07 9-Mar-07 10-Mar-07 11-Mar-07 12-Mar-07
Tem
p, C
, or
Spe
ed, m
/s
Tamb
Thub
Wind
Tcenter Center Cabinet
Hub
Ambient
Wind Speed
- Hub temperature within a few degrees of outside ambient temperature
p. 19
James M
aughan, G
E W
ind
Wind Turbine Relia
bility W
orksh
op
0 30 60 90
120
150
180
Lost Production, MWhr
Blade angle asymmetry
Battery charging voltage
Planned repair
Rotor CCU fault voltage
Program start PLC
Rotor CCU collective faults
Pitch thyristor 1 fault
Motor protection
Main switch released
Rotor CCU fault current
Planned Maintenance
Gearbox oil pressure
Weather downtime
Yaw runaway
Typ
ical Fault A
nd Ava
ilability D
ata
Unavaila
bility
Lost P
roductio
n
Field Solutio
ns D
eveloped
��� ���� �
��� ���� �
��� �
New
Syste
m D
esig
ns
��� �
0 50
100
150
200
250
300
Blade angle asymmetry
Battery charging voltage
Planned repair
Rotor CCU fault voltage
Program start PLC
Rotor CCU collective faults
Pitch thyristor 1 fault
Cabinet Over temperature
Motor protection
Main switch released
Rotor CCU fault current
Planned Maintenance
Gearbox oil pressure
Weather downtime
Yaw runaway
Unavailability (hrs)
Cabinet Over temperature
p. 20James Maughan, GE Wind Wind Turbine Reliability Workshop
GE Pitch Control System
00 12000024000 48000 72000 96000
Time, hrs
Cum
ulat
ive
Num
ber
of T
rips
120000
System Redesign
• Higher torque and temperature capability
• Improved batteries and chargers
• PWM conversion, reduced slip ring current
• Digital control, fewer components
• Ethernet-based diagnostics
Validation
• Fault counts at validation site
• Half old system, half new
GE Redesign
Legacy System
p. 21James Maughan, GE Wind Wind Turbine Reliability Workshop
1.5 MW DFIG IGBT-based Power Converter
60 Hz to Grid
AC from Generator
DC to 60 Hz AC
AC to DC
Power Conditioning
Liquid Cooling
DC linkControlCards
60 Hz to Grid
AC from Generator
DC to 60 Hz AC
AC to DC
Power Conditioning
Liquid Cooling
DC linkControlCards
Grid Voltageat Converter
Reactive Current
Power
0.200 sec
Continued operationGrid Disturbance
Power Converter• Replaces multiple vendors• Based on GE’s motor drive
and generator exciter technology
• Enhanced diagnostics, capability, reliability
• Operates under authority of legacy main control
Low Voltage Ride Through
• Digital monitoring and control technology
• Remains connected during grid disturbance
• Uses reactive power flow to ride through disturbance
p. 22James Maughan, GE Wind Wind Turbine Reliability Workshop
Electrical System Simplification and Integration
System Redesign
• Integrates converter, main controller, and power distribution into a single cabinet
• Ethernet diagnostics and control across converter, pitch, control, generator, all electrical
• Modernized software, blockware, and toolkit, - identical to Mark VIe control in gas turbines
• Discrete components in top box replaced with circuit boards
• Prototypes in installation now
p. 23James Maughan, GE Wind Wind Turbine Reliability Workshop
Summary - Improving GE’s Fleet Reliability
0%
10%
20%30%
40%50%
60%70%
80%
90%
100%
0 0.2 0.4 0.6 0.8 1Availability
0%
10%
20%30%
40%50%
60%70%
80%
90%
100%
0 0.2 0.4 0.6 0.8 1
Per
cent
of F
leet
Summary
• Focus on total reliability- component failure rates andsystem faults
• Increase production and revenue
• Reduce operating costs
• Grow the industry It All Depends on Reliability