scispace - formally typeset
Journal ArticleDOI: 10.1080/15732479.2020.1743326

A case study on risk-based maintenance of wind turbine blades with structural health monitoring

04 Mar 2021-Structure and Infrastructure Engineering (Taylor & Francis)-Vol. 17, Iss: 3, pp 302-318
Abstract: The paper presents a case study demonstrating the methods used to estimate the value of the information (VoI) delivered by a structural health monitoring (SHM) system. The monitored object is a bla...

... read more

Citations
  More

11 results found


Open accessJournal ArticleDOI: 10.1175/JAMC-D-20-0033.1
Abstract: 6 Deep convection and the related occurrence of hail, intense precipitation and wind gusts 7 represent a hazard to a range of energy infrastructure including wind turbine blades. Wind 8 turbine blade leading edge erosion (LEE) is caused by the impact of falling hydrometeors onto 9 rotating wind turbine blades. It is a major source of wind turbine maintenance costs and energy 10 losses from wind farms. In the United States Southern Great Plains (SGP), where there is 11 widespread wind energy development, deep convection and hail events are common, increasing 12 the potential for precipitation-driven LEE. A 25-day Weather Research and Forecasting (WRF) 13 model simulation conducted at convection-permitting resolution and using a detailed 14 microphysics scheme is carried out for the SGP to evaluate the effectiveness in modelling the 15 wind and precipitation conditions relevant to LEE potential. WRF output for these properties is 16 evaluated using radar observations of precipitation (including hail) and reflectivity, in situ wind 17 speed measurements and wind power generation. This research demonstrates some skill for the 18 primary drivers of LEE. Wind speeds, rainfall rates and precipitation totals show good agreement 19 with observations. The occurrence of precipitation during power producing wind speeds is also 20 shown to exhibit fidelity. Hail events frequently occur during periods when wind turbines are 21 Early Online Release: This preliminary version has been accepted for publication in Journal of Applied Meteorology and limatology, may be fully cited, and has been assigned DOI The final typeset copyedited article will replace the EOR at the above DOI when it is published. © 20 ological Society C 20 American Meteor 10.1175/JAMC-D-20-0033.1. D ow naded rom http:urnals.am ets.org/jam c/article-oi/10.1175/JAM C -D -20-003/4992799/jam cd2033.pdf by gest on 03 Sptem er 2020

... read more

7 Citations


Open accessJournal ArticleDOI: 10.3390/MA14051124
Leon Mishnaevsky Mishnaevsky1Institutions (1)
27 Feb 2021-Materials
Abstract: Various scenarios of end-of-life management of wind turbine blades are reviewed. "Reactive" strategies, designed to deal with already available, ageing turbines, installed in the 2000s, are discussed, among them, maintenance and repair, reuse, refurbishment and recycling. The main results and challenges of "pro-active strategies", designed to ensure recyclability of new generations of wind turbines, are discussed. Among the main directions, the wind turbine blades with thermoplastic and recyclable thermoset composite matrices, as well as wood, bamboo and natural fiber-based composites were reviewed. It is argued that repair and reuse of wind turbine blades, and extension of the blade life has currently a number of advantages over other approaches. While new recyclable materials have been tested in laboratories, or in some cases on small or medium blades, there are remaining technological challenges for their utilization in large wind turbine blades.

... read more

Topics: Turbine blade (59%), Wind power (57%)

7 Citations


Open accessDOI: 10.5278/VBN.PHD.ENG.00036
01 Jan 2018-
Abstract: The tendency within engineering is to build increasingly large structures while minimizing material use. Needless to say, this leads to less conservative designs and, as such, an increased demand on regular inspection of the structures to ensure that they maintain adequate reliability through their life cycle. The inspections are conventionally conducted by sending out trained personnel to visually assess the integrity of the structures. This procedure can, however, be associated with high costs due to operational downtime and, for structures located in terrain not easily accessible, transportation. A general consensus is that vibration-based structural health monitoring (SHM), which involves implementing a damage identi cation strategy to monitor structural integrity using vibration measurements, can play a role in reducing the inspection costs. Numerous SHM techniques have been suggested, and while the task of detecting whether damage is present or not has been resolved with reasonable success, a reliable solution has not yet been presented for the next logical step; namely, to locate the detected damage. There are many reasons as to why vibration-based damage localization has not yet found the level of industrial applicability that one would anticipate after decades of research. One of these reasons is undoubtedly that the vibration features used in the process, such as modal parameters, lack sensitivity to damage compared to the sensitivity to noise and other variabilities. In the present thesis, three new vibration-based damage localization schemes are proposed that, in one way or another, address the noted sensitivity issue. The rst exploration is the CWT-GDTKEO scheme, whose methodological premise is to seek for damage-induced changes in signal-processed mode shapes of the structure in question. More speci cally, the scheme incorporates continuous wavelet transformation (CWT) and a generalized discrete Teager-Kaiser energy operator (GDTKEO) to capture these changes, and the damage location is attained using a simple metric comparing processed signals from the states prior and posterior to damage. In this way, the scheme relies on su ciently accurate estimation of the required mode shapes, which, in many application scenarios, can be di cult to achieve due to noise and/or poor excitation. The obvious drawbacks of the CWT-GDTKEO scheme have led to exploration of what are considered the two main contributions of this thesis. The rst one is the Subspace Exclusion Zone (SEZ) scheme, which, under certain input conditions, circumvents system identi cation. The scheme locates damage by reconstructing shifts in measured eld quantities using subspaces indexed by postulated boundaries, the so-called exclusion zones (EZs). The methodological concept rests on the fact that shifts in any eld quantity outside the boundary of an EZ encompassing the damage can be generated from stress elds acting on the aforementioned boundary. The EZs, which are formed in a theoretical model of the structure prior to damage, are of user-de ned size, thus information on size and type of damage is precluded to provide a net robustness gain. Application examples are presented that clearly demonstrate the robustness of the SEZ scheme in instances allowing for a system identi cation-free con guration. The second main contribution of the thesis is the Shaped Damage Locating Input Distribution (SDLID) scheme, which operates unconditionally free of system identi cation. The methodological premise is to deploy controllable inputs that are tailored to actively interrogate one structural subdomain at a time. When the subdomain containing damage is rendered dormant, the e ect of damage and, as such, its induced shift in steady-state vibrations are canceled. In this way, the SDLID scheme facilitates damage localization using only few output sensors; in fact, one well-placed may su ce. This low demand on output sensors is an attractive feature, which is conventionally only achieved when employing an approach based on guided waves. However, unlike this approach with high-frequency waves, which is merely suitable for local integrity inspection because of small wavelengths and high damping, the SDLID scheme can operate in a broad band of frequencies.

... read more

5 Citations


Open accessJournal ArticleDOI: 10.3390/COATINGS10121223
14 Dec 2020-THE Coatings
Abstract: A damage mechanism based approach to the structural health monitoring of wind turbine blades is formulated. Typical physical mechanisms of wind turbine blade degradation, including surface erosion, adhesive fatigue, laminate cracking and in some cases compressive kinking and failure are reviewed. Examples of a local, damage mechanism based approach to the structural health monitoring of wind turbine blades are demonstrated, including the monitoring of leading edge erosion of wind turbine blades, adhesive bond failure, plydrop delamination, static and dynamic plydrop tests, and bolt and laminate fatigue. The examples demonstrate the possibilities of monitoring specific damage mechanisms, and specific localizations of wind turbine blades.

... read more

Topics: Turbine blade (62%), Wind power (51%)

4 Citations


Open accessJournal ArticleDOI: 10.1186/S43065-021-00027-0
Wei-Heng Zhang1, Wei-Heng Zhang2, Da-Gang Lu1, Jianjun Qin3  +3 moreInstitutions (5)
Abstract: The concept of Value of Information (VoI) has attracted significant attentions within the civil engineering community over especially the last decade. Triggered by the increasing focus on structural health monitoring, availability of data and emerging techniques of Big Data analysis and Artificial Intelligence, important insights on how to take benefit from VoI in structural integrity management have been gained. This literature review starts out with a summary of the historical developments and contains (1) a summary of two different VoI analysis origins, (2) a compilation of existing VoI analyses research and (3) current engineering interpretations and applications of VoI in the field of civil and infrastructure engineering. VoI analysis has roots in communication theory and Bayesian decision analysis in conjunction with utility theory. Starting point is thus taken in brief introduction of these theoretical foundations, followed by a discussion on the relevant modelling aspects such as information, probability and utility modelling. A detailed review of relevant existing research is presented, divided into the following main areas: computational methods, optimal sensor placement and engineering risk management. Finally, by way of conclusion and outlook, challenges and some promising directions for VoI analysis in the field of civil and infrastructure engineering are identified.

... read more

3 Citations


References
  More

25 results found


Open accessJournal ArticleDOI: 10.1007/S10479-005-5724-Z
Abstract: The cross-entropy (CE) method is a new generic approach to combinatorial and multi-extremal optimization and rare event simulation. The purpose of this tutorial is to give a gentle introduction to the CE method. We present the CE methodology, the basic algorithm and its modifications, and discuss applications in combinatorial optimization and machine learning.

... read more

1,673 Citations


Open accessJournal ArticleDOI: 10.1061/(ASCE)EM.1943-7889.0000024
Daniel Straub1Institutions (1)
Abstract: A generic framework for stochastic modeling of deterioration processes is proposed, based on dynamic Bayesian networks. The framework facilitates computationally efficient and robust reliability analysis and, in particular, Bayesian updating of the model with measurements, monitoring, and inspection results. These properties make it ideally suited for near-real time applications in asset integrity management and deterioration control. The framework is demonstrated and investigated through two applications to probabilistic modeling of fatigue crack growth.

... read more

Topics: Dynamic Bayesian network (55%), Bayesian network (54%), Bayesian inference (52%) ... read more

175 Citations


Journal ArticleDOI: 10.1080/15732470412331289314
Abstract: Development of reliability-based management of inspection, monitoring, maintenance and repair (IMMR) of various types of offshore structures is described, with a focus on management of hull damage due to crack growth and corrosion. Operational experiences with respect to degradation of various types of offshore structures are summarized. The interrelation between design criteria and IMMR is emphasized. Explicit design for robustness in terms of an accidental collapse limit state and monitoring by the use of the leak before break principle to identify damage are highlighted. It is shown how design for robustness, choice of inspection method and scheduling as well as repair strategy, need to be implemented to obtain an acceptable risk for various types of offshore structures. Finally, the particular features of reliability based structural reassessment for extension of the service life, are briefly outlined and exemplified.

... read more

144 Citations


Journal ArticleDOI: 10.1016/J.MARSTRUC.2016.02.002
01 Mar 2016-Marine Structures
Abstract: Due to the nature of the fatigue phenomena it is well known that small changes in basic assumptions for fatigue analysis can have significant influence on the predicted crack growth lives. Calculated fatigue lives based on the S–N approach are sensitive to input parameters. Fracture mechanics analysis is required for prediction of crack sizes during service life in order to account for probability of detection after an inspection event. Analysis based on fracture mechanics needs to be calibrated to that of fatigue test data or S–N data. Calculated probabilities of fatigue failure using probabilistic methods are even more sensitive to the analysis methodology and to input parameters used in the analyses. Thus, use of these methods for planning inspection requires considerable knowledge and engineering skill. Therefore the industry has asked for guidelines that can be used to establish reliable inspection results using these methods. During the last years DNV GL has performed a joint industry project on establishing probabilistic methods for planning in-service inspection for fatigue cracks in offshore structures. The recommendations from this project are now included in a Recommended Practice. The essential features of the probabilistic methods developed for this kind of inspection planning are described in this paper.

... read more

100 Citations


Open accessJournal ArticleDOI: 10.1016/J.EJOR.2016.05.059
Abstract: An optimisation model and a solution method for maintenance routing and scheduling at offshore wind farms are proposed. The model finds the optimal schedule for maintaining the turbines and the optimal routes for the crew transfer vessels to service the turbines along with the number of technicians required for each vessel. The model takes into account multiple vessels, multiple periods (days), multiple Operation & Maintenance (O&M) bases, and multiple wind farms. We develop an algorithm based on the Dantzig–Wolfe decomposition method, where a mixed integer linear program is solved for each subset of turbines to generate all feasible routes and maintenance schedules for the vessels for each period. The routes have to consider several constraints such as weather conditions, the availability of vessels, and the number of technicians available at the O&M base. An integer linear program model is then proposed to find the optimal route configuration along with the maintenance schedules that minimise maintenance costs, including travel, technician and penalty costs. The computational experiments show that the proposed optimisation model and solution method find optimal solutions to the problem in reasonable computing times.

... read more

Topics: Offshore wind power (55%), Schedule (52%), Linear programming (50%)

98 Citations


Performance
Metrics
No. of citations received by the Paper in previous years
YearCitations
20221
20216
20203
20181