Applications and Modeling Techniques of Wind Turbine Power Curve for Wind Farms - A Review

In the wind energy industry, the power curve represents the relationship between the “wind speed” at the hub height and the corresponding “active power” to be generated. It is the most versatile condition indicator and of vital importance in several key applications, such as wind turbine selection, capacity factor estimation, wind energy assessment and forecasting, and condition monitoring, among others. Ensuring an effective implementation of the aforementioned applications mostly requires a modeling technique that best approximates the normal properties of an optimal wind turbines operation in a particular wind farm. This challenge has drawn the attention of wind farm operators and researchers towards the “state of the art” in wind energy technology. This paper provides an exhaustive and updated review on power curve based applications, the most common anomaly and fault types including their root-causes, along with data preprocessing and correction schemes (i.e., filtering, clustering, isolation, and others), and modeling techniques (i.e., parametric and non-parametric) which cover a wide range of algorithms. More than 100 references, for the most part selected from recently published journal articles, were carefully compiled to properly assess the past, present, and future research directions in this active domain

Induction of Plasmodium falciparum-Specific CD4+ T Cells and Memory B Cells in Gabonese Children Vaccinated with RTS,S/AS01E and RTS,S/AS02D

The recombinant circumsporozoite protein (CS) based vaccine, RTS,S, confers protection against Plasmodium falciparum infection in controlled challenge trials and in field studies. The RTS,S recombinant antigen has been formulated with two adjuvant systems, AS01 and AS02, which have both been shown to induce strong specific antibody responses and CD4 T cell responses in adults. As infants and young children are particularly susceptible to malaria infection and constitute the main target population for a malaria vaccine, we have evaluated the induction of adaptive immune responses in young children living in malaria endemic regions following vaccination with RTS,S/AS01(E) and RTS,S/AS02(D). Our data show that a CS-specific memory B cell response is induced one month after the second and third vaccine dose and that CS-specific antibodies and memory B cells persist up to 12 months after the last vaccine injection. Both formulations also induced low but significant amounts of CS-specific IL-2(+) CD4(+) T cells one month after the second and third vaccine dose, upon short-term in vitro stimulation of whole blood cells with peptides covering the entire CS derived sequence in RTS,S. These results provide evidence that both RTS,S/AS01(E) and RTS,S/AS02(D) induced adaptive immune responses including antibodies, circulating memory B cells and CD4(+) T cells directed against P. falciparum CS protein.ClinicalTrials.gov NCT00307021

Early Detection and Diagnosis of Wind Turbine Abnormal Conditions Using an Interpretable Supervised Variational Autoencoder Model

The operation and maintenance of wind turbines benefit from reliable information on the wind turbine condition. Data-driven models use data from the supervisory data acquisition system. In particular, great performance is reported for artificial intelligence models. However, the lack of interpretability limits their effective industrial implementation. The present work introduces a new condition-monitoring approach for wind turbines featuring a built-in visualization tool that confers interpretability upon the model outcomes. The proposed approach is based on a supervised implementation of the variational autoencoder model, which allows the projection of the wind turbine system onto a low-dimensional representation space. Three outcomes follow from such representation: a health indicator for the early detection of abnormal conditions, a classifier providing the diagnosis status, and a visualization tool depicting the wind turbine condition as a trajectory in a 2D plot. The approach is implemented with a vast database. Two case studies demonstrate the potential of the proposed approach. The proposed health indicator detects the main bearing overtemperature 11 days before the control system alarm, one week earlier than a competing approach. Study cases illustrate that the built-in visualization tool enhances the interpretability and trust in the model outcomes, thus supporting wind turbine operation and maintenance

Comparison of power curve monitoring methods

Performance monitoring is an important aspect of operating wind farms. This can be done through the power curve monitoring (PCM) of wind turbines (WT). In the past years, important work has been conducted on PCM. Various methodologies have been proposed, each one with interesting results. However, it is difficult to compare these methods because they have been developed using their respective data sets. The objective of this actual work is to compare some of the proposed PCM methods using common data sets. The metric used to compare the PCM methods is the time needed to detect a change in the power curve. Two power curve models will be covered to establish the effect the model type has on the monitoring outcomes. Each model was tested with two control charts. Other methodologies and metrics proposed in the literature for power curve monitoring such as areas under the power curve and the use of statistical copulas have also been covered. Results demonstrate that model-based PCM methods are more reliable at the detecting a performance change than other methodologies and that the effectiveness of the control chart depends on the types of shift observed

Élaboration d’un questionnaire d’autoévaluation de la compétence interculturelle des directions d’établissement scolaire de langue française au Québec et au Nouveau-Brunswick

En cette ère d’inclusion, force est d’admettre que les directions d’établissement scolaire, qui baignent ou non dans un contexte de diversité ethnoculturelle, linguistique et religieuse, ont intérêt à développer leur compétence interculturelle. Or, comment conscientiser les directions et savoir si elles ont développé une telle compétence ? Compte tenu d’un tel enjeu, l’objectif de cet article est de présenter le processus d’élaboration d’un questionnaire d’autoévaluation de la compétence interculturelle des directions d’établissement scolaire de langue française au Québec et au Nouveau-Brunswick, qui comprend 1) la recension de questionnaires portant sur cette compétence, 2) la construction d’une banque d’items, 3) le recueil de preuves basées sur le contenu, 4) l’élaboration de la version préliminaire du questionnaire d’autoévaluation, 5) le prétest et 6) l’accumulation de preuves basées sur la structure interne. Finalement, un questionnaire d’autoévaluation préliminaire de 43 items est proposé. Les limites de la recherche et les retombées de ce questionnaire d’autoévaluation préliminaire sont mentionnées en conclusion.In this era of inclusion, it is clear that school principals, who live in a context of ethnocultural, linguistic and religious diversity, as well as those who do not, would benefit from developing their intercultural competence. However, how can school principals be more conscious of whether they have developed such competence? Considering this issue, the objective of this article is to present the process of developing a self-evaluation questionnaire on intercultural competence for French-language school principals in Quebec and New Brunswick, consisting of : 1) a review of questionnaires on this competence, 2) the creation of a bank of items, 3) the collection of sources of evidence based on the test content, 4) the development of the preliminary version of the self-evaluation questionnaire, 5) the pre-test and 6) the collection of evidence based on the internal structure. Finally, a preliminary 43-item self-evaluation questionnaire is proposed. The limits of the research and the impact of this preliminary self-evaluation questionnaire are mentioned in the conclusion.Nesta era de inclusão, é preciso admitir que os diretores das escolas, estando ou não imersos num contexto de diversidade etnocultural, linguística e religiosa, têm interesse em desenvolver a sua competência intercultural. Porém, como conscientizar a gestão escolar e saber se ela desenvolveu tal competência? Face a tal desafio, o objetivo deste artigo é apresentar o processo de elaboração de um questionário de autoavaliação sobre a competência intercultural de diretores de escolas de língua francesa no Quebec e em New Brunswick, que inclui 1) a recensão de questionários relacionados com esta competência, 2) construção de um banco de itens, 3) recolha de evidências com base no conteúdo, 4) elaboração da versão preliminar do questionário de autoavaliação , 5) pré-teste e 6) acumulação de evidências com base na estrutura interna. Finalmente, é proposto um questionário preliminar de autoavaliação de 43 itens. As limitações da investigação e o impacto deste questionário de autoavaliação preliminar são mencionados na conclusão

Comparison of power curve monitoring methods

Performance monitoring is an important aspect of operating wind farms. This can be done through the power curve monitoring (PCM) of wind turbines (WT). In the past years, important work has been conducted on PCM. Various methodologies have been proposed, each one with interesting results. However, it is difficult to compare these methods because they have been developed using their respective data sets. The objective of this actual work is to compare some of the proposed PCM methods using common data sets. The metric used to compare the PCM methods is the time needed to detect a change in the power curve. Two power curve models will be covered to establish the effect the model type has on the monitoring outcomes. Each model was tested with two control charts. Other methodologies and metrics proposed in the literature for power curve monitoring such as areas under the power curve and the use of statistical copulas have also been covered. Results demonstrate that model-based PCM methods are more reliable at the detecting a performance change than other methodologies and that the effectiveness of the control chart depends on the types of shift observed

Applications and Modeling Techniques of Wind Turbine Power Curve for Wind Farms—A Review

In the wind energy industry, the power curve represents the relationship between the “wind speed” at the hub height and the corresponding “active power” to be generated. It is the most versatile condition indicator and of vital importance in several key applications, such as wind turbine selection, capacity factor estimation, wind energy assessment and forecasting, and condition monitoring, among others. Ensuring an effective implementation of the aforementioned applications mostly requires a modeling technique that best approximates the normal properties of an optimal wind turbines operation in a particular wind farm. This challenge has drawn the attention of wind farm operators and researchers towards the “state of the art” in wind energy technology. This paper provides an exhaustive and updated review on power curve based applications, the most common anomaly and fault types including their root-causes, along with data preprocessing and correction schemes (i.e., filtering, clustering, isolation, and others), and modeling techniques (i.e., parametric and non-parametric) which cover a wide range of algorithms. More than 100 references, for the most part selected from recently published journal articles, were carefully compiled to properly assess the past, present, and future research directions in this active domain