Post on 06-Jan-2016
description
European Wind Energy Conference 2010, Poland European Wind Energy Conference 2010, Poland
Reliability Analysis and Prediction Reliability Analysis and Prediction
of Wind Turbine Gearboxesof Wind Turbine Gearboxes
K. Smolders, K. Smolders, Hansen Transmissions International
H. Long H. Long (speaker), Durham University
Y. Feng, Y. Feng, Durham University
P. Tavner, P. Tavner, Durham University
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Outline of the PresentationOutline of the Presentation
1
• Field reliability data from public sources;
• Objectives of this study;
• Generic WT gearbox configurations and modular structure;
• Estimation of failure rates of critical components;
• Reliability prediction of generic WT gearboxes.
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Field Reliability and Downtime DataField Reliability and Downtime Data
2
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Recent Reports on Gearbox FailuresRecent Reports on Gearbox Failures• E.ON UK report on the first year of operation of an
offshore wind farm in the UK (2005, 30 turbines):o There were 43 incidences of major unplanned work;o 39 were caused by failures within in the gearbox;
All of these were failures of the bearings; 27 were in the intermediate speed shaft; The remaining 12 were in the high speed shaft.
• Gear tooth failures were reported in 2.5 MW turbines:o 50 turbines were in need of repair and refit in August
2007.
• Design for Reliability to eliminate design faults and to improve operational performance.
3
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Objectives of this StudyObjectives of this Study
• To develop generic WT gearbox configurations;
• To develop generic and flexible gearbox modular structure;
• To develop reliability block diagrams;
• To estimate failure rates of the critical components;
• To provide quantitative reliability prediction of WT gearboxes at modular level, for different designs;
• To identify reliability critical components in a WT gearbox.
4
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Gearbox Generic ConfigurationsGearbox Generic Configurations• Two WT configurations are considered: R80 and R100
• Three gearbox designs: GB-R80, GB-R100-S, and GB-R100-A
Characteristics R80 R100
Nominal Power (MW) 1.5~2.0 3.0~5.0
Rotor Diameter (m) 80~90 120~130
Hub Height (m) 60~100 100~120
Rotational Speed (rpm) 10~20 14~15
• GB-R80:GB-R80: 1 planetary stage + 2 parallel stages =Ratio 100Ratio 100
• GB-R100-S: GB-R100-S: 1 planetary (spur) + 1 planetary (helical)=Ratio 35Ratio 35
• GB-R100-A:GB-R100-A: 2 planetary stages + 1 parallel stage =Ratio 126 Ratio 126
5
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Gearbox Modular StructureGearbox Modular StructureGearbox
Planetary Stage Parallel Stage Housing Lubrication Accessories
Gear (ring, planet, sun)
Spline (sun)
Bearing (planet, planet carrier)
Shaft (planet carrier, planet, sun)
Gear (wheel, pinion)
Bearing (left, right)
Shaft (parallel)
Keyway (wheel, generator)
Torque arm
Joint (bolts, pins)
Oil
Pump
Sealing
Piping
Filter
Cooler
Sensor (oil, temp, particulate)
Sensor
Breather
6
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Gearbox ConfigurationsGearbox Configurations
LS-SUN
LSS PS
PS
LS-IS
HS-IS
HSS
HSS
HS-ISIS-SUN
IS-PS
IS-PS
LS-SUN
LS-PS
LS-PSLSS
GB-R80GB-R80 GB-R100-AGB-R100-A
7
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Reliability Block DiagramsReliability Block Diagrams
LS-I parallel HS parallel
Housing Lubrication Accessories
HS-I parallelLS planetary A
A
GB-R80GB-R80
IS planetary HS-I parallel Housing
Lubrication Accessories
LS planetary B
B
GB-R100-SGB-R100-S
C
C
IS planetary HS-I parallel
Housing Lubrication Accessories
HS parallelLS planetary
GB-R100-AGB-R100-A
8
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Estimation of Failure RatesEstimation of Failure Rates
Components of R80 LS Planetary Module
Failure Rate(failures/year)
Quantity
LSS 0.0025 1
LSS Bearing RS 0.00009 1
LSS Bearing GS 0.00009 1
LS-PS 0.0025 3
LS-PS Bearing 0.00022 3
LS-PS Wheel 0.00017 3
LS Ring Wheel 0.00017 1
LS Sun Pinion 0.00017 1
LS Sun Shaft 0.0025 1
LS Sun Shaft Spline 0.00025 1
Total: 0.01444
• Require data of individual components of each module• Consider R80 LS Planetary Module:
• “Handbook of Reliability Prediction Procedures for Mechanical Equipment”;
• Published by the US Naval Surface Warfare Centre (NSWC07);
• Provided prediction formulae and data sheets for gears, bearings, splines, shafts, ...
9
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Formulae for Gears and BearingsFormulae for Gears and Bearings
Gears:Gears: GVGTGLGAGPGSBGG CCCCCC,
Considering the base failure rate and multiplication factors (operating speed, loading, misalignment, viscosity of lubricant, temperature, AGMA service factor).
tCWnyBBEBE CCCC, Bearings:Bearings:
Where λBE is the failure rate of the bearing under specific
operation conditions, calculated by using the base failure rate of the bearing λBE,B and the multiplication factors by
considering the applied load Cy, lubricant Cn, water
contamination CCW, and the operating temperature Ct.10
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Failure Rates of R80 LS Planetary ModuleFailure Rates of R80 LS Planetary Module
Components of R80 Components of R80
LS Planetary ModuleLS Planetary ModuleFailure RateFailure Rate
(failures/year)(failures/year)QuantityQuantity
LSS 0.0025 1
LSS Bearing RS 0.00009 1
LSS Bearing GS 0.00009 1
LS-PS 0.0025 3
LS-PS Bearing 0.00022 3
LS-PS Wheel 0.00017 3
LS Ring Wheel 0.00017 1
LS Sun Pinion 0.00017 1
LS Sun Shaft 0.0025 1
LS Sun Shaft Spline 0.00025 1
Total: 0.01444
Assumptions: Assumptions: • Constant failure rates
• Base failure rates
• For shafts, keyways, structural components, joints, oils, pumps, sealings, piping, filters, coolers, heaters, sensors and breather:
yearfailuresBG /0025.0, yearfailuresBGS /00025.0,
valueLonbasedBBE 10, 4
yearfailuresothers /0025.0
11
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Prediction of Failure RatesPrediction of Failure Rates
12
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
Observations of the Predicted ResultsObservations of the Predicted Results• The high speed parallel stage is found to be the most
unreliable module;
• A planetary intermediate speed stage is less reliable than a parallel intermediate speed stage;
• The planetary intermediate speed stage seems less reliable than the planetary low speed stage;
• The lubrication subsystem has an important effect on reliability;
• The housing and the accessories are the least reliability critical components.
13
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
ConclusionsConclusions
14
• A reliability prediction method has been developed, based on Reliability Block Diagram and Gearbox Modular Structure;
• Predicted results show that the high speed stage and planetary intermediate speed stage are less reliable;
• Estimation of failure rates at component level is in need of improvement;
• Field failure data through Life Data analysis or Weibull analysis can improve reliability prediction;
• This requires collaborations between end-users, WT manufacturers, gearbox and bearing manufacturers.
European Wind Energy Conference 2010, European Wind Energy Conference 2010, Poland Poland
AcknowledgementAcknowledgement• Financial support of the EC through the EU FP7
Reliawind, Project No. 212966;
• Reliawind project partners:– SKF;
– Gamesa;
– Alstom Ecotecnia;
– Relex Italy;
– Garrad Hassan;
– ABB OY;
– LM Glasfiber;
– SZTAKI.
15