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Evaluation of Ice Detection Systems for Wind Turbines Final Report

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Evaluation of Ice Detection Systems for Wind Turbines Final Report Weather Forecasts Renewable Energies Air and Climate Environmental IT Genossenschaft METEOTEST Fabrikstrasse 14, CH-3012 Bern Tel. +41 (0)31 307 26 26 Fax +41 (0)31 307 26 10 [email protected], www.meteotest.ch Bern, February 16, 2016 Evaluation of ice detection systems for wind turbines Final report VGB Research Project No. 392 report_v8_final.docx/rc METEOTEST 2 Disclaimer All information presented in this report is solely based on documents provided by the manufacturers of the ice detection systems as well as publicly available reports, papers and presentations. No data analysis has been carried out by Meteotest for this report. Especially the information on the accuracy of the systems has not been checked or validated by Meteotest or by TÜV NORD. Acknowledgements The research project "Evaluation of ice detection systems for wind turbines" was funded by VGB PowerTech e.V., which is kindly acknowledged. The project was initiated and supervised by the VGB Technical Committee "Wind Energy." The au- thors would like to thank the companies EnBW, Enercity (Stadtwerke Hannover), Energiewerkstatt, ESB Renewables, EVN Naturkraft, Fortech, GDF Suez Canada (now Engie) , GDF Suez Europe (now Engie), RheinEnergie, Vattenfall and WSB Service Deutschland for their active participation in the survey among wind-turbine operators conducted within the project. Finally the authors wish to thank all manu- facturers of ice detection systems for their active and transparent collaboration in the project. Version Date Document Project Number 1 16.02.2016 Final Report 15_025 Editing Name Date Created by René Cattin, Dr. Ulla Heikkilä 22.12.2015 Controlled by Dr. Ulla Heikkilä 23.12.2015 Approved by Dr. Saskia Bourgeois 30.12.2015 Reviewed by Oliver Raupach, Felix Storck 29.01.2016 TÜV NORD SysTec GmbH & Co.KG Meteotest guarantees its clients a careful and professional execution of the offered services. Any liability, particu- larly also for consequential losses, is waived. report_v8_final.docx METEOTEST 3 Summary Atmospheric icing has a significant impact on the development and the operation of wind parks. To reach an optimal performance, the turbine must first be able to de- tect ice on the rotor blades immediately when it occurs. Second, it must provide a signal which states that the rotor blade is free of ice and thus normal operation can be resumed. The goal of this report is to provide an independent overview on ice detection sys- tems commercially available. The report consists of basics and important definitions regarding icing on structures. The main part is a detailed description of the ice de- tection systems based on information provided by the system manufacturers as well as publicly available documentation. Afterwards, the different systems are com- pared in an evaluation matrix. Additionally, short overviews on ice protection sys- tems for wind turbines and on the state of the art regarding icing forecasts are giv- en. There are two different types of ice detection systems being evaluated and com- pared in the report: . Nacelle based systems: ice detection with instruments installed at one point on the nacelle of a wind turbine. Rotor blade based systems: ice detection with devices installed on the ro- tor blade. All nacelle based systems measure instrumental icing and therefore do not repre- sent the effective conditions on the rotor blade. For a safe and efficient operation of wind turbines under icing conditions, measuring rotor icing is mandatory. 10 nacelle based systems and methods have been evaluated. The Labkotec LID- 3300IP and the Goodrich 0871LH1 model have the highest technical maturity and the highest number of systems in use. Furthermore, they are the only certified sys- tems. Several independent field studies exist for most systems. These studies show that all systems have their shortcomings under specific conditions. 5 blade based systems and methods have been evaluated. The power curve method is applied very frequently. The Bosch Rexroth BladeControl system has the highest number of systems in use. The other systems have significantly smaller numbers of systems in use. This is explained by the fact, that the fos4IceDetection, Wölfel IDD.Blade and eologix are very new systems. All blade based systems are certified. No independent field studies exist for the blade based systems. The power curve method is the only blade based system which is not able to detect rotor icing during stand still of the wind turbine. All systems except the eologix sys- tem require a minimum wind speed of 2 m/s or higher to be able to detect rotor ic- ing. The eologix system is the only system one which does not require access to real-time operational data of the wind turbine (pitch angle, rotational speed, wind report_v8_final.docx METEOTEST 4 speed). At the same time, eologix is the only blade based system which measures icing at specific spots on the rotor blade. The other systems are able to detect ice anywhere on the blade with increasing sensitivity towards the blade tip. The power curve method as well as the fos4IceDetection and the eologix system do not require any electrical wires in the blade. All blade based systems can be retrofitted. report_v8_final.docx METEOTEST 5 Contents 1 Introduction .................................................................................................... 7 2 Icing basics and important definitions ......................................................... 9 2.1 Cold climate ............................................................................................... 9 2.2 Atmospheric icing ...................................................................................... 9 2.3 Phases of an icing event .......................................................................... 10 2.4 IEA site classification ............................................................................... 11 2.5 Ice Detection ........................................................................................... 12 3 Evaluated systems ....................................................................................... 14 3.1 Nacelle based approaches and systems.................................................. 14 3.2 Blade based approaches and systems .................................................... 14 3.3 Systems not manufactured anymore ....................................................... 14 4 Evaluation of nacelle based approaches and systems ............................. 15 4.1 Temperature & relative humidity .............................................................. 15 4.2 Heated versus unheated anemometer ..................................................... 17 4.3 Combitech IceMonitor .............................................................................. 19 4.4 Goodrich 0871LH1, 0872F1 and 0872E3 ................................................. 26 4.5 HoloOptics T40 series ............................................................................. 33 4.6 Ice Meister Model 9734-SYSTEM ............................................................ 39 4.7 Labkotec LID-3300IP Ice Detector ........................................................... 42 4.8 Leine Linde Systems IPMS ...................................................................... 49 4.9 Meteorological Monitoring Station PMS ................................................... 55 4.10 Sommer IDS-10 ....................................................................................... 63 5 Evaluation of blade based approaches and systems ................................ 66 5.1 Power Curve and Pitch Angle .................................................................. 66 5.2 BLADEcontrol (Bosch Rexroth) ............................................................... 68 5.3 eologix ..................................................................................................... 75 5.4 fos4Ice Detection (fos4X) ........................................................................ 82 5.5 Wölfel IDD.Blade ..................................................................................... 88 6 Systems not manufactured anymore.......................................................... 96 6.1 HAICMONice/Hainzl .................................................................................. 96 6.2 Infralytic ................................................................................................... 97 6.3 MOOG/Insensys ...................................................................................... 98 7 Comparison nacelle based systems ......................................................... 100 8 Comparison blade based systems ........................................................... 102 9 Overview on ice protection systems ........................................................ 105 10 Overview on icing forecasts ...................................................................... 106 10.1 Introduction ............................................................................................ 106 report_v8_final.docx METEOTEST 6 10.2 Components of an icing forecast system ............................................... 106 10.3 Summary and outlook ............................................................................ 109 10.4 References ............................................................................................ 110 report_v8_final.docx METEOTEST 7 1 Introduction Atmospheric icing has a significant impact on the development and the operation of wind parks. The ice
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