Statistics of extreme wind events and power curve monitoring

Monitoring the power performance of an offshore WECusing nacelle-based wind measurements and the Langevin power curveMatthias Wchter, Patrick Milan, Philip Rinn, Joachim PeinkeForWind Center for Wind Energy ResearchInstitute of Physics, Carl von Ossietky University of Oldenburg

EWEA 2013 Vienna, 4.-7.2.2013

Gefrdert auf Grund eines Beschlusses des Deutschen BundestagesProjekttrgerKoordination01Challenge of wind power conversion

InputTurbulent wind:Intermittent,extreme eventsOutputTurbulent powerConversionComplex, nonlinear interaction

Wchter, Milan, Rinn, PeinkePower curve monitoringEWEA 2013 Vienna12Wind energy conversion dynamicsHighly dynamical process on short time scalesDriven by turbulent wind

How to obtain the response dynamics of WEC?Possible from wind and power data ~1Hz

Wchter, Milan, Rinn, PeinkePower curve monitoringEWEA 2013 Vienna3Langevin power curveDrift function reflects average slope of power signalDrift field shows deterministic dynamics of energy conversionStable fixed points constitute Langevin Power Curve

Important propertiesShows short-time dynamics (~1s)Quick detection of changesMultiple fixed points possibleState-based vs. global averaging (as of IEC 61400-12)AV 4: REpower 5M

Wchter, Milan, Rinn, PeinkePower curve monitoringEWEA 2013 Vienna4Langevin power curve monitoringAV 4: REpower 5M

Daily LPC over 10 days, February 2011Wind: nacelle anemometerArtifact caused by wind measurement

Unfortunately no turbine anomalies here

Changes in dynamical behavior are detected

Wchter, Milan, Rinn, PeinkePower curve monitoringEWEA 2013 Vienna5Langevin power curve monitoringExample showing anomalyFAST simulation of WindPact 1.5 turbineArtificial pitch failure: one blade fixed to 45LPC after 1000min of failureNOT AV 4

(Significant) Pitch failure clearly detected

[Muecke, PhD Thesis, to be published]Wchter, Milan, Rinn, PeinkePower curve monitoringEWEA 2013 Vienna

6Nacelle lidar-based Langevin power curveLidar scanner developed by SWE, U StuttgartDeployed at AREVA Wind M5000prototype, BHV1 day measurementAREVA Wind M5000 prototype

Large potential of nacelle lidar-based power curve measurements

Wchter, Milan, Rinn, PeinkePower curve monitoringEWEA 2013 Vienna7Nacelle lidar development at ForWindPrototype developed within LIDAR II at Marine Physics group, U OldenburgSpinner integrationRobustCost-efficientField testing early 2013

Wchter, Milan, Rinn, PeinkePower curve monitoringEWEA 2013 Vienna8ConclusionsLangevin power curve suitable for monitoring of power performanceQuick and clear detection of anomaliesLarge potential for nacelle-based lidar wind measurementsSpinner-mounted lidar developed at ForWind OldenburgThank you for your attention!

Thanks to: SWE U Stuttgart, REpower Systems SE, Areva Wind GmbH, and the RAVE initiativeWchter, Milan, Rinn, PeinkePower curve monitoringEWEA 2013 Vienna