scholarly journals Quantification of the Information Loss Resulting from Temporal Aggregation of Wind Turbine Operating Data

2021 ◽  
Vol 11 (17) ◽  
pp. 8065
Author(s):  
Mattia Beretta ◽  
Karoline Pelka ◽  
Jordi Cusidó ◽  
Timo Lichtenstein

 SCADA operating data are more and more used across the wind energy domain, both as a basis for power output prediction and turbine health status monitoring. Current industry practice to work with this data is by aggregating the signals at coarse resolution of typically 10-min averages, in order to reduce data transmission and storage costs. However, aggregation, i.e., downsampling, induces an inevitable loss of information and is one of the main causes of skepticism towards the use of SCADA operating data to model complex systems such as wind turbines. This research aims to quantify the amount of information that is lost due to this downsampling of SCADA operating data and characterize it with respect to the external factors that might influence it. The issue of information loss is framed by three key questions addressing effects on the local and global scale as well as the influence of external conditions. Moreover, recommendations both for wind farm operators and researchers are provided with the aim to improve the information content. We present a methodology to determine the ideal signal resolution that minimized storage footprint, while guaranteeing high quality of the signal. Data related to the wind, electrical signals, and temperatures of the gearbox resulted as the critical signals that are largely affected by an information loss upon aggregation and turned out to be best recorded and stored at high resolutions. All analyses were carried out using more than one year of 1 Hz SCADA data of onshore wind farm counting 12 turbines located in the UK. 

2021 ◽  
Vol 12 (1) ◽  
pp. 69
Author(s):  
Lu Wei ◽  
Zheng Qian ◽  
Yan Pei ◽  
Jingyue Wang

Wind farm operators are overwhelmed by a large amount of supervisory control and data acquisition (SCADA) alarms when faults occur. This paper presents an online root fault identification method for SCADA alarms to assist operators in wind turbine fault diagnosis. The proposed method is based on the similarity analysis between an unknown alarm vector and the feature vectors of known faults. The alarm vector is obtained from segmented alarm lists, which are filtered and simplified. The feature vector, which is a unique signature representing the occurrence of a fault, is extracted from the alarm lists belonging to the same fault. To mine the coupling correspondence between alarms and faults, we define the weights of the alarms in each fault. The similarities is measured by the weighted Euclidean distance and the weighted Hamming distance, respectively. One year of SCADA alarms and maintenance records are used to verify the proposed method. The results show that the performance of the weighted Hamming distance is better than that of the weighted Euclidean distance; 84.1% of alarm lists are labeled with the right root fault.


2020 ◽  
Author(s):  
Charlotte Strang-Moran

Abstract. Subsea power cable failure is an issue which is detrimental to both export cables for Offshore Transmission Owners (OFTO) and inter-array cables for wind farm operators. As the offshore wind sector advances in technology, size and capability, future sites will be farther offshore to harness the most powerful of wind conditions. As technology adapts and offshore wind develops, subsea cables are also required to acclimatise and become more reliable. This paper will review current subsea cable failures in the UK sector. In addition, it will provide an overview of the methodology used to initiate the failure trending, and further discuss the importance of accurate data and the constraints on the initial findings.


2013 ◽  
Vol 13 (24) ◽  
pp. 12215-12231 ◽  
Author(s):  
Z. S. Stock ◽  
M. R. Russo ◽  
T. M. Butler ◽  
A. T. Archibald ◽  
M. G. Lawrence ◽  
...  

Abstract. We examine the effects of ozone precursor emissions from megacities on present-day air quality using the global chemistry–climate model UM-UKCA (UK Met Office Unified Model coupled to the UK Chemistry and Aerosols model). The sensitivity of megacity and regional ozone to local emissions, both from within the megacity and from surrounding regions, is important for determining air quality across many scales, which in turn is key for reducing human exposure to high levels of pollutants. We use two methods, perturbation and tagging, to quantify the impact of megacity emissions on global ozone. We also completely redistribute the anthropogenic emissions from megacities, to compare changes in local air quality going from centralised, densely populated megacities to decentralised, lower density urban areas. Focus is placed not only on how changes to megacity emissions affect regional and global NOx and O3, but also on changes to NOy deposition and to local chemical environments which are perturbed by the emission changes. The perturbation and tagging methods show broadly similar megacity impacts on total ozone, with the perturbation method underestimating the contribution partially because it perturbs the background chemical environment. The total redistribution of megacity emissions locally shifts the chemical environment towards more NOx-limited conditions in the megacities, which is more conducive to ozone production, and monthly mean surface ozone is found to increase up to 30% in megacities, depending on latitude and season. However, the displacement of emissions has little effect on the global annual ozone burden (0.12% change). Globally, megacity emissions are shown to contribute ~3% of total NOy deposition. The changes in O3, NOx and NOy deposition described here are useful for quantifying megacity impacts and for understanding the sensitivity of megacity regions to local emissions. The small global effects of the 100% redistribution carried out in this study suggest that the distribution of emissions on the local scale is unlikely to have large implications for chemistry–climate processes on the global scale.


Author(s):  
John Glasson

The Offshore Wind sector is a major, dynamic, and rapidly evolving renewable energy industry. This is particularly so in Europe, and especially in the UK. Associated with the growth of the industry has been a growth of interest in community benefits as voluntary measures provided by a developer to the host community. However, in many cases, and for some of the large North Sea distant offshore wind farms, the benefits packages have been disparate and pro rata much smaller than for the well-established onshore wind farm industry. However, there are signs of change. This paper explores the issues of community benefits for the UK offshore sector and evolving practice, as reflected in a macro study of the adoption of community benefits approaches across the industry. This is followed by a more in-depth micro- approach, which explores approaches that have been adopted in three case studies of recent OWF projects — Aberdeen, Beatrice and the Hornsea Array. Whilst there is still much divergence in practice, there are also examples of some convergence, and the development of a more replicable practice. Particularly notable is the adoption of annual community benefits funds, as the key element of community benefits schemes/agreements between developers, local authorities and local communities.


2018 ◽  
Vol 21 (18) ◽  
pp. 3431-3439
Author(s):  
Paraskevi Seferidi ◽  
Anthony A Laverty ◽  
Jonathan Pearson-Stuttard ◽  
Maria Guzman-Castillo ◽  
Brendan Collins ◽  
...  

AbstractObjectiveAn industry levy on sugar-sweetened beverages (SSB) was implemented in the UK in 2018. One year later, Brexit is likely to change the UK trade regime with potential implications for sugar price. We modelled the effect of potential changes in sugar price due to Brexit on SSB levy impacts upon CHD mortality and inequalities.DesignWe modelled a baseline SSB levy scenario; an SSB levy under ‘soft’ Brexit, where the UK establishes a free trading agreement with the EU; and an SSB levy under ‘hard’ Brexit, in which World Trade Organization tariffs are applied. We used the previously validated IMPACT Food Policy model and probabilistic sensitivity analysis to estimate the effect of each scenario on CHD deaths prevented or postponed and life-years gained, stratified by age, sex and socio-economic circumstance, in 2021.SettingEngland.SubjectsAdults aged 25 years or older.ResultsThe SSB levy was associated with approximately 370 (95 % uncertainty interval 220, 560) fewer CHD deaths and 4490 (2690, 6710) life-years gained in 2021. Associated reductions in CHD mortality were 4 and 8 % greater under ‘soft’ and ‘hard’ Brexit scenarios, respectively. The SSB levy was associated with approximately 110 (50, 190) fewer CHD deaths in the most deprived quintile compared with 60 (20, 100) in the most affluent, under ‘hard’ Brexit.ConclusionsOur study found the SSB levy resilient to potential effects of Brexit upon sugar price. Even under ‘hard’ Brexit, the SSB levy would yield benefits for CHD mortality and inequalities. Brexit negotiations should deliver a fiscal and regulatory environment which promotes population health.


2021 ◽  
Vol 8 (1) ◽  
Author(s):  
Dan G. O’Neill ◽  
Rowena M.A. Packer ◽  
Peter Francis ◽  
David B. Church ◽  
Dave C. Brodbelt ◽  
...  

Abstract Background The French Bulldog is a highly popular dog breed but is linked with many serious health issues. A holistic view of breed health in French Bulldogs would assist efforts to appreciate the overall health strengths and weaknesses in the French Bulldog and to take appropriate steps to mitigate these. Based on random sampling of French Bulldogs and non-French Bulldogs under primary veterinary care during 2016 within the VetCompass Programme, a cohort study design was used to estimate the one-year (2016) period prevalence of the most commonly diagnosed disorders in each group. Risk factor analysis used multivariable logistic regression modelling methods. Results The analysis included 2,781 French Bulldogs and 21,850 non-French Bulldogs. French Bulldogs were younger (1.51 years, IQR 0.86 – 2.77 vs. 4.48 years, IQR 1.94 – 8.14) (p < 0.001) and lighter (12.45 kg, IQR 11.00 – 14.03 versus 13.80 kg, IQR 8.10 – 25.12) (p < 0.001) than non-French Bulldogs. Of 43 common specific-level disorders across both groups, French Bulldogs had significantly increased adjusted odds of 20/43 (46.5 %) disorders and significantly reduced adjusted odds of 11/43 (25.6 %) disorders compared to non-French Bulldogs. Highly predisposed disorders in French Bulldogs included stenotic nares (OR 42.14; 95 % CI 18.50 to 95.99; p < 0.001), Brachycephalic Obstructive Airway Syndrome (OR 30.89; 95 % CI 20.91 to 45.64; p < 0.001), aural discharge (OR 14.40; 95 % CI 9.08 to 22.86; p < 0.001), skin fold dermatitis (OR 11.18; 95 % CI 7.19 to 17.40; p < 0.001) and dystocia (OR 9.13; 95 % CI 5.17 to 16.13; p < 0.001). At a grouped-level of diagnostic precision, French Bulldogs had increased adjusted odds of 12/32 (37.5 %) disorders and reduced adjusted odds of 6/32 (18.8 %) disorders compared to non-French Bulldogs. Conclusions These results identified ultra-predispositions with worryingly higher odds in French Bulldogs for several disorders, suggesting that the health of French Bulldogs has diverged substantially from, and may be lower than, the health of the wider non-French Bulldog population. Many of these predispositions are closely associated with the conformational extremes that define the French Bulldog breed. Shifting the typical conformation of the French Bulldog population towards a more moderate phenotype is proposed as a logical opportunity to reduce the serious health issues endemic in the French Bulldog breed.


2013 ◽  
Author(s):  
Madhur A. Khadabadi ◽  
Karen B. Marais

Wind turbine maintenance is emerging as an unexpectedly high component of turbine operating cost and there is an increasing interest in managing this cost. Here, we present an alternative view of maintenance as a value-driver, and develop an optimization algorithm to maximize the value delivered by maintenance. We model the stochastic deterioration of the turbine in two dimensions: the deterioration rate, and the extent of deterioration, and view maintenance as an operator that moves the turbine to an improved state in which it can generate more power and so earn more revenue. We then use a standard net present value (NPV) approach to calculate the value of the turbine by deducting the costs incurred in the installation, operations and maintenance from the revenue due to the power generation. The application of our model is demonstrated using several scenarios with a focus on blade deterioration. We evaluate the value delivered by implementing blade condition monitoring systems (CMS). A higher fidelity CMS allows the blade state to be determined with higher precision. With this improved state information, an optimal maintenance strategy can be derived. The difference between the value of the turbine with and without CMS can be interpreted as the value of the CMS. The results indicate that a higher fidelity (and more expensive) condition monitoring system (CMS) does not necessarily yield the highest value, and, that there is an optimal level of fidelity that results in maximum value. The contributions of this work are twofold. First, it is a practical approach to wind turbine valuation and operation that takes operating and market conditions into account. This work should therefore be useful to wind farm operators and investors. Second, it shows how the value of a CMS can be explicitly assessed. This work should therefore be useful to CMS manufacturers and wind farm operators.


2009 ◽  
Vol 9 (14) ◽  
pp. 5281-5297 ◽  
Author(s):  
I. Pison ◽  
P. Bousquet ◽  
F. Chevallier ◽  
S. Szopa ◽  
D. Hauglustaine

Abstract. In order to study the spatial and temporal variations of the emissions of greenhouse gases and of their precursors, we developed a data assimilation system and applied it to infer emissions of CH4, CO and H2 for one year. It is based on an atmospheric chemical transport model and on a simplified scheme for the oxidation chain of hydrocarbons, including methane, formaldehyde, carbon monoxide and molecular hydrogen together with methyl chloroform. The methodology is exposed and a first attempt at evaluating the inverted fluxes is made. Inversions of the emission fluxes of CO, CH4 and H2 and concentrations of HCHO and OH were performed for the year 2004, using surface concentration measurements of CO, CH4, H2 and CH3CCl3 as constraints. Independent data from ship and aircraft measurements and satellite retrievals are used to evaluate the results. The total emitted mass of CO is 30% higher after the inversion, due to increased fluxes by up to 35% in the Northern Hemisphere. The spatial distribution of emissions of CH4 is modified by a decrease of fluxes in boreal areas up to 60%. The comparison between mono- and multi-species inversions shows that the results are close at a global scale but may significantly differ at a regional scale because of the interactions between the various tracers during the inversion.


2014 ◽  
pp. 1400-1418
Author(s):  
Irina Turner

The colonization of discourses (Chilton & Schäffner, 2002) is a wide-spread phenomenon of globalization and naturally affects politics. The power of business-speak over politics and the media seems to be steadily increasing. Most vulnerable to that development, which the author calls businification, seem to be countries in transition that have to assert themselves rhetorically on a global scale while keeping traditional voters content at home. In an application of critical discourse analysis, the chapter seeks to trace this businification by comparing three presidential state-of-the-nation-addresses (SoNA) of three South African presidents after one year in office (1995, 2000, and 2010). Through contextualizing these texts with their media reception from a corpus of 15 newspaper articles reporting on the speeches, the outer influences on the core text become transparent. The findings suggest a parallelism between a growing professionalism in politics and the businification of political rhetoric whose development cannot be viewed as exclusively negative.


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