Academic literature on the topic 'DFIG MODEL'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'DFIG MODEL.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "DFIG MODEL"

1

Wang, Shaoping, Jun Zhou, and Zhaoxia Duan. "Finite Frequency H∞ Control for Doubly Fed Induction Generators with Input Delay and Gain Disturbance." Sustainability 15, no. 5 (March 2, 2023): 4520. http://dx.doi.org/10.3390/su15054520.

Full text
Abstract:
Due to the rapid development of wind power, the stable operation of doubly fed induction generators (DFIGs) has attracted much attention. This paper focuses on the finite frequency (FF) H∞ control for the DFIG with input delay, aiming to reduce the effects of current harmonic interferences and gain disturbances on the DFIG and improve the stability of the system. First, a DFIG state–space model with input delay under current harmonics was constructed. Second, based on the DFIG state–space model, an FF H∞ state-feedback controller was designed from the frequency domain perspective, which makes the DFIG stable and robust against harmonic interferences and gain disturbances. Third, via the generalized Kalman–Yakubovich–Popov (GKYP) lemma and the Lyapunov theory, the FF H∞ performance was evaluated in the form of linear matrix inequalities (LMIs), and then the state feedback FF H∞ controller was designed. Finally, the simulation results showed the efficiency of the proposed approach.
APA, Harvard, Vancouver, ISO, and other styles
2

Chen, Changqing, and Xinran Li. "Configuration Method and Multi-Functional Strategy for Embedding Energy Storage into Wind Turbine." Energies 14, no. 17 (August 28, 2021): 5354. http://dx.doi.org/10.3390/en14175354.

Full text
Abstract:
This paper proposes a Configuration method for energy storage (ES), in which the ES inertia of ES is equal to an equal capacity synchronous generator. The purpose is to enhance the frequency modulation capability of double-fed induction generator (DFIG) and wind power consumption. Through the proposed method, the system inertia can remain unchanged after the DFIGs replacing the conventional turbines. During the DFIG rotor speed recovery, the ES releases energy to compensate for sudden changes in active power. On this basis, the DFIG and ES structure model is created, and the ES control strategy is optimized, thereby effectively improving the DFIG frequency modulation capability. Besides, in the non-frequency modulation period, the ES is used to suppress wind power fluctuations, thereby improving system wind power consumption and ES utilization. Simulation results indicate, in the ES-embedded wind turbine structure model, the combination of the ES Configuration method and multi-functional strategy significantly improves the frequency modulation ability and anti-interference performance of a single DFIG. Moreover, the wind power consumption and ES utilization are improved, and the ES achieves additional value.
APA, Harvard, Vancouver, ISO, and other styles
3

Li, Lei, Yabo Liang, Jian Niu, Jianan He, Haitao Liu, Bin Li, Chao Li, and Yunzhu Cao. "The Fault Ride-Through Characteristics of a Double-Fed Induction Generator Using a Dynamic Voltage Restorer with Superconducting Magnetic Energy Storage." Applied Sciences 13, no. 14 (July 13, 2023): 8180. http://dx.doi.org/10.3390/app13148180.

Full text
Abstract:
With the prevalence of renewable energy sources such as wind power in the power system, analyzing the fault characteristics of systems composed of DFIGs is becoming increasingly important. Therefore, this article analyzes, at first theoretically, the fault characteristics of a doubly fed induction generator (DFIG) during fault periods. It was found that the fault current of the DFIG exhibited the frequency offset phenomenon, which is affected by the depth of voltage dips and can negatively impact traditional distance protection. Furthermore, a method using a dynamic voltage restorer (DVR) based on superconducting magnetic energy storage (SMES) was adopted to compensate for the fault voltage of DFIG, which can mitigate the voltage dips of the DFIG. This method can not only achieve the fault ride through for DFIG but also significantly improve the frequency offset of the fault current during fault periods. Finally, a model composed of a 2.5 MW DFIG-based wind turbine and a 2.5 MW DVR-based SMES was built using a real-time digital simulator (RTDS) platform, and the simulation results showed that the fault stator voltage of DFIG can be compensated at a rated value of 0.69 kV, and the frequency of fault current can be maintained at 50 Hz These results validate the excellent performance of the method in achieving the fault ride through of DFIG and improving the frequency offset of the fault current by comparing multiple type faults while employing different protection methods.
APA, Harvard, Vancouver, ISO, and other styles
4

Kavitha, A., and A. V. Suresh. "A Novel Inter Connection of DFIG with Grid in Separate Excitation SMES System with Fuzzy Logic Control." Bulletin of Electrical Engineering and Informatics 4, no. 1 (March 1, 2015): 43–52. http://dx.doi.org/10.11591/eei.v4i1.312.

Full text
Abstract:
The use of doubly fed induction generators (DFIGs) in wind turbines has become quite common over the last few years. DFIG wind turbine is an integrated part of distributed generation system. This paper presents a Fuzzy based controller SMES unit in DFIG for improving the ac output on grid side. The excitation system is composed of the rotor-side converter, the grid-side converter, the dc chopper and the superconducting magnet. The superconducting magnet is connected with the dc side of the two converters, which can handle the active power transfer with the rotor of DFIG and the power grid independently, even thou Sutton small fluctuations are occur in active power on AC side. For smoothening the AC output power waveform a Fuzzy based controller is introduced in SMES controller unit, which implemented using simulation developed in MATLAB/ SIMULINK 7.2 version. The model of the FUZZY controlled SMES based excitation system for DFIG is established, and the simulation tests are performed to evaluate the system performance.
APA, Harvard, Vancouver, ISO, and other styles
5

Sun, Dongyang, Fanyi Meng, and Wenqiang Shen. "Study on Suppression Strategy for Broadband Sub-Synchronous Oscillation in Doubly-Fed Wind Power Generation System." Applied Sciences 12, no. 16 (August 20, 2022): 8344. http://dx.doi.org/10.3390/app12168344.

Full text
Abstract:
In the power transmission of doubly-fed induction generators (DFIGs), sub-synchronous oscillation (SSO) can occur due to the influence of series compensation capacitance and long-distance transmission. SSO not only affects the output of the DFIG but also leads to oscillation diffusion. In order to solve the problem of disturbance in the control of the DFIG rotor side converter (RSC) under SSO, an adaptive quasi-resonant controller is proposed for the suppression of SSO. This strategy focuses on the propagation path of and frequency change in the SSO in the RSC control system and suppresses the SSO current in the wideband through the cooperative control of the back-stepping controller and the adaptive quasi-resonant controller. In this way, the stator-side output of the DFIG will not be affected by SSO, thus avoiding the amplification of the sub-synchronous power of the line by the DFIG. A simulation model and experimental platform were built to verify the suppression effect of this control strategy on the DFIG stator sub-synchronous current at different SSO frequencies. The results show that the proposed strategy has a good suppression effect on broadband SSO.
APA, Harvard, Vancouver, ISO, and other styles
6

Song, Shaojian, Peichen Guan, Bin Liu, Yimin Lu, and HuiHwang Goh. "Impedance Modeling and Stability Analysis of DFIG-Based Wind Energy Conversion System Considering Frequency Coupling." Energies 14, no. 11 (June 1, 2021): 3243. http://dx.doi.org/10.3390/en14113243.

Full text
Abstract:
Impedance-based stability analysis is an effective method for addressing a new type of SSO accidents that have occurred in recent years, especially those caused by the control interaction between a DFIG and the power grid. However, the existing impedance modeling of DFIGs is mostly focused on a single converter, such as the GSC or RSC, and the influence between the RSC and GSC, as well as the frequency coupling effect inside the converter are usually overlooked, reducing the accuracy of DFIG stability analysis. Hence, the entire impedance is proposed in this paper for the DFIG-based WECS, taking coupling factors into account (e.g., DC bus voltage dynamics, asymmetric current regulation in the dq frame, and PLL). Numerical calculations and HIL simulations on RT-Lab were used to validate the proposed model. The results indicate that the entire impedance model with frequency coupling is more accurate, and it is capable of accurately predicting the system’s possible resonance points.
APA, Harvard, Vancouver, ISO, and other styles
7

Putri, Tri Wahyu Oktaviana, Agus Yogianto, and Ibnu Hajar. "Model Doubly Fed Induction Generator (DFIG) untuk Analisis Performa Kontrol pada Pembangkit Listrik Tenaga Angin." Energi & Kelistrikan 12, no. 2 (December 22, 2020): 179–85. http://dx.doi.org/10.33322/energi.v12i2.1095.

Full text
Abstract:
Studi mengenai pengoperasian pembangkit listrik dari energi terbarukan dengan tenaga angin khususnya terkait dengan peran sistem kontrol pada pembangkit listrik tenaga angin relatif masih sangat terbatas. Peran sistem kontrol sendiri sangat penting di dalam konversi daya pembangkit listrik seperti ini. Oleh sebab itu untuk mengetahui serta menyelidiki pengaruh sistem kontrol konverter daya pada pembangkit listrik tenaga angin khususnya dengan Double-Fed Induction Generator (DFIG) dibutuhkan pemodelan dari pembangkit listrik tenaga angin dengan DFIG serta sistem kontrol yang dapat digunakan untuk simulasi pada jaringan atau sistem tenaga listrik. Penelitian dengan demikian bertujuan untuk menghasilkan model pembangkit listrik tenaga angin dengan generator DFIG beserta sistem kontrolnya yang dapat mengatur konversi daya secara optimal pada operasi yang terkoneksi ke jaringan listrik. Beberapa tahapan dilakukan pada penelitian ini yang terdiri dari kajian literatur, persiapan perangkat untuk simulasi memakai MATLAB/Simulink, pemodelan DFIG dengan penurunan persamaan yang berlaku, penyederhanaan model, disain kontrol, simulasi dan analisis. Pada tahapan penelitian ini hasil yang didapat merupakah sebagian tahapan penelitian yaitu mendapatkan pemodelan DFIG yang disederhanakan. Model DFIG yang disederhanakan ini diperoleh setelah melalui perumusan persamaan matematis dari rangkaian ekuivalen DFIG, menurunkan persamaan untuk model transien DFIG dan menyusun model DFIG dalam bentuk state space. Selanjutnya penyederhanaan dari bentuk state space diperoleh hubungan antara stator dan rotor DFIG.
APA, Harvard, Vancouver, ISO, and other styles
8

Shuaibu, Musayyibi, and Adamu Saidu Abubakar. "An Improved Dynamic Voltage Restorer Model for Ensuring Fault Ride-Through Capability of DFIG-based Wind Turbine Systems." ELEKTRIKA- Journal of Electrical Engineering 19, no. 1 (April 24, 2020): 9–16. http://dx.doi.org/10.11113/elektrika.v19n1.205.

Full text
Abstract:
Renewable energy sources (RES) are being integrated to electrical grid to complement the conventional sources in meeting up with global electrical energy demand. Among the RES, Wind Energy Conversion Systems (WECS) have gained global electricity market competitiveness especially the Doubly Fed Induction Generator (DFIG)-based Wind Turbines (WTs) because of flexible regulation of active and reactive power, higher power quality, variable speed operation, four quadrant converter operation and better dynamic performance. Grid connected DFIG-based WTs are prone to disturbances due to faults in the network which made the utilization of the power generated a major concern. The grid code requirement for integrating the DFIGs to grid specified that they must remain connected and support the grid stability during grid disturbances of up to 1500milliseconds. The ability of the DFIG WT system to uphold to the grid codes requirement is termed the Fault Ride – Through (FRT). This paper presented a 1.5MW grid connected DFIG-based WT model with a Dynamic Voltage Restorer (DVR) for FRT capability enhancement. The design and simulation were performed in MATLAB/Simulink software. The test system was subjected to disturbances leading to Low Voltage Ride – Through (LVRT), Zero Voltage Ride – Through (ZVRT) and High Voltage Ride – Through (HVRT) considering three – phase balanced fault and single line to ground fault. The performance of improved model of DVR shows enhancement over conventional DVR in terms of voltage compensation and fault current mitigation.
APA, Harvard, Vancouver, ISO, and other styles
9

Shahriari, Sayyed Ali Akbar. "Modelling and dynamic state estimation of a doubly fed induction generator wind turbine." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 39, no. 6 (September 11, 2020): 1393–409. http://dx.doi.org/10.1108/compel-07-2019-0277.

Full text
Abstract:
Purpose This paper aims to propose an 18th-order nonlinear model for doubly fed induction generator (DFIG) wind turbines. Based on the proposed model, which is more complete than the models previously developed, an extended Kalman filter (EKF) is used to estimate the DFIG state variables. Design/methodology/approach State estimation is a popular approach in power system control and monitoring because of minimizing measurement noise level and obtaining non-measured state variables. To estimate all state variables of DFIG wind turbine, it is necessary to develop a model that considers all state variables. So, an 18th-order nonlinear model is proposed for DFIG wind turbines. EKF is used to estimate the DFIG state variables based on the proposed model. Findings An 18th-order nonlinear model is proposed for DFIG wind turbines. Furthermore, based on the proposed model, its state variables are estimated. Simulation studies are done in four cases to verify the ability of the proposed model in the estimation of state variables under noisy, wind speed variation and fault condition. The results demonstrate priority of the proposed model in the estimation of DFIG state variables. Originality/value Evaluating DFIG model to estimate its state variables precisely.
APA, Harvard, Vancouver, ISO, and other styles
10

Li, Xiao-ming, Xiu-yu Zhang, Hong Cao, Zhong-wei Lin, Yu-guang Niu, and Jian-guo Wang. "Neural Adaptive Decentralized Coordinated Control with Fault-Tolerant Capability for DFIGs under Stochastic Disturbances." Mathematical Problems in Engineering 2017 (2017): 1–16. http://dx.doi.org/10.1155/2017/6271341.

Full text
Abstract:
At present, most methodologies proposed to control over double fed induction generators (DFIGs) are based on single machine model, where the interactions from network have been neglected. Considering this, this paper proposes a decentralized coordinated control of DFIG based on the neural interaction measurement observer. An artificial neural network is employed to approximate the nonlinear model of DFIG, and the approximation error due to neural approximation has been considered. A robust stabilization technique is also proposed to override the effect of approximation error. A H2 controller and a H∞ controller are employed to achieve specified engineering purposes, respectively. Then, the controller design is formulated as a mixed H2/H∞ optimization with constrains of regional pole placement and proportional plus integral (PI) structure, which can be solved easily by using linear matrix inequality (LMI) technology. The results of simulations are presented and discussed, which show the capabilities of DFIG with the proposed control strategy to fault-tolerant control of the maximum power point tracking (MPPT) under slight sensor faults, low voltage ride-through (LVRT), and its contribution to power system transient stability support.
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "DFIG MODEL"

1

Piyasinghe, Lakshan Prageeth. "Dynamic Phasor Based Analysis and Control in Renewable Energy Integration." Scholar Commons, 2015. http://scholarcommons.usf.edu/etd/6015.

Full text
Abstract:
The objective of this dissertation is to carry out dynamic modeling, analysis and control of power systems with Renewable Energy Sources (RES) such as: Photovoltaic (PV) power sources and wind farms. The dissertation work is mainly focused on microgrid since it plays a major role in modern power systems and tend to have higher renewable power penetration. Two main theoretical concepts, dynamic phasor and impedance modeling have been adopted to model and analyze the power systems/mocrogrids with RES. The initial state calculation which is essential for small signal analysis of a system is carried out as the first step of the dissertation work. Dynamic phasor and impedance modeling techniques have been utilized to model and analyze power systems/micogrids as the second phase of the work. This part consists of two main studies. First case investigates the impedance modeling of Thyristor Controller Series Capacitor (TCSC) for sub-synchronous resonance (SSR) analysis where a wind farm is connected to a power system through series compensated line. Second case utilizes the dynamic phasor concept to model a microgrid in unbalanced condition. Here the unbalance is caused by a single phase PV connected to the microgrid. Third Phase of the dissertation work includes upper level control of the microgrid. Here prediction and optimization control for a microgrid with a wind farm, a PV system, an energy storage system and loads is evaluated. The last part of the dissertation work focuses on real time modeling and hardware in loop simulation test bed for microgrid applications. This dissertation has led to four journal papers (three accepted, one submitted) and five conference papers.
APA, Harvard, Vancouver, ISO, and other styles
2

Ho, Viet Bun, and Xuan Thanh Le. "Research on the wind power’s ability in supplying electrical energy for 6kV grid of underground mines in Quang Ninh, Vietnam." Technische Universität Dresden, 2016. https://tud.qucosa.de/id/qucosa%3A32486.

Full text
Abstract:
Quang Ninh province, Vietnam has a rich wind power resources. This type of energy will be soon utilized for generating power to supply all industrial sites including mining corporations. Because of geological characteristics, wind power stations are located near the 6kV grid of mining areas, therefore it needs to make the analysis about the connection ability of wind power generators to the grids. The paper presents the connection model of a wind turbine and 6kV grids. Based on this model, the simulations of system’s possible operating mode are implemented. The conclusions about the suitable operating modes of wind turbine are pointed out to give the operators and grid managers a general observation for the possibility of connecting a wind turbine to 6kV grid
Tỉnh Quảng Ninh là một trong những địa phương giàu tiềm năng về năng lượng gió. Theo phân tích, loại năng lượng này sẽ sớm được đưa vào cung cấp điện năng cho các khu công nghiệp trong đó có các công ty than. Do đặc thù địa lý, các trạm phát phong năng được đặt khá gần các lưới điện 6kV của mỏ, vì thế cần tiến hành phân tích khả năng kết nối trực tiếp các máy phát điện gió với lưới điện này. Bài báo giới thiệu mô hình kết nối máy phát điện gió với lưới 6kV. Các mô phỏng về các chế độ vận hành có thể có của lưới cũng được thực hiện. Các kết luận về chế độ vận hành thích hợp của tua bin gió được đúc rút để giúp người vận hành, các nhà quản lý lưới điện có được cái nhìn tổng quan về khả năng kết nối tua bin gió với lưới điện 6kV.
APA, Harvard, Vancouver, ISO, and other styles
3

Alsmadi, Yazan M. "Modeling, Advance Control, and Grid Integration of Large-Scale DFIG-Based Wind Turbines during Normal and Fault Ride-Through Conditions." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1437140573.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Ngo, Van Quang Binh. "Algorithmes de conception de lois de commande prédictives pour les systèmes de production d’énergie." Thesis, Université Paris-Saclay (ComUE), 2017. http://www.theses.fr/2017SACLC031/document.

Full text
Abstract:
Cette thèse vise à élaborer de nouvelles stratégies de commande basées sur la commande prédictive pour le système de génération d’énergie éolienne. La topologie des systèmes de production éolienne basées sur le Générateur Asynchrone à Double Alimentation (GADA) qui convient à des plateformes de génération dans la gamme de puissance de 1.5 à 6 MW est abordée. Du point de vue technologique, le convertisseur à trois niveaux et clampé par le neutre (3L-NPC) est considéré comme une bonne solution pour une puissance élevée en raison de ses avantages: capacité à réduire la distorsion harmonique de la tension de sortie et du courant, et augmentation de la capacité du convertisseur grâce à une tension réduite appliquée à chaque semi-conducteur de puissance. Une description détaillée de la commande prédictive à ensemble de commande fini (FCS-MPC) avec un horizon de prédiction de deux pas est présentée pour deux boucles de régulation: celle liée au convertisseur connecté au réseau et celle du convertisseur connecté au GADA. Le principe de la commande repose sur l’utilisation d’un modèle de prédiction permettant de prédire le comportement du système pour chaque état de commutation du convertisseur. La minimisation d’une fonction de coût appropriée prédéfinie permet d’obtenir la commutation optimale à appliquer au convertisseur. La thèse étudie premièrement les problèmes liées à la compensation du temps de calcul de la commande et au choix et aux pondérations de la fonction de coût. Ensuite, le problème de stabilité de la commande FCS-MPC est abordé en considérant une fonction de Lyapunov dans la minimisation de la fonction de coût. Finalement, une étude sur la compensation des effets des temps morts du convertisseur est présentée
This thesis aims to elaborate new control strategies based on Model Predictive control for wind energy generation system. We addressed the topology of doubly fed induction generator (DFIG) based wind generation systems which is suitable for generation platform power in the range in 1.5-6 MW. Furthermore, from the technological point of view, the three-level neutral-point clamped (3L-NPC) inverter configuration is considered a good solution for high power due to its advantages: capability to reduce the harmonic distortion of the output voltage and current, and increase the capacity of the converter thanks to a decreased voltage applied to each power semiconductor.In this thesis, we presented a detailed description of finite control set model predictive control (FCS-MPC) with two step horizon for two control schemes: grid and DFIG connected 3L-NPC inverter. The principle of the proposed control scheme is to use system model to predict the behaviour of the system for every switching states of the inverter. Then, the optimal switching state that minimizes an appropriate predefined cost function is selected and applied directly to the inverter.The study of issues such as delay compensation, computational burden and selection of weighting factor are also addressed in this thesis. In addition, the stability problem of FCS-MPC is solved by considering the control Lyapunov function in the design procedure. The latter study is focused on the compensation of dead-time effect of power converter
APA, Harvard, Vancouver, ISO, and other styles
5

Mansouri, Farouk. "Modèles de programmation des applications de traitement du signal et de l'image sur cluster parallèle et hétérogène." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAT063/document.

Full text
Abstract:
Depuis une dizaine d'année, l'évolution des machines de calcul tend vers des architectures parallèles et hétérogènes. Composées de plusieurs nœuds connectés via un réseau incluant chacun des unités de traitement hétérogènes, ces grilles offrent de grandes performances. Pour programmer ces architectures, l'utilisateur doit s'appuyer sur des modèles de programmation comme MPI, OpenMP, CUDA. Toutefois, il est toujours difficile d'obtenir à la fois une bonne productivité du programmeur, qui passe par une abstraction des spécificités de l'architecture et performances. Dans cette thèse, nous proposons d'exploiter l'idée qu'un modèle de programmation spécifique à un domaine applicatif particulier permet de concilier ces deux objectifs antagonistes. En effet, en caractérisant une famille d'applications, il est possible d'identifier des abstractions de haut niveau permettant de les modéliser. Nous proposons deux modèles spécifiques au traitement du signal et de l'image sur cluster hétérogène. Le premier modèle est statique. Nous lui apportons une fonctionnalité de migration de tâches. Le second est dynamique, basé sur le support exécutif StarPU. Les deux modèles offrent d'une part un haut niveau d'abstraction en modélisant les applications de traitement du signal et de l'image sous forme de graphe de flot de données et d'autre part, ils permettent d'exploiter efficacement les différents niveaux de parallélisme tâche, données, graphe. Ces deux modèles sont validés par plusieurs implémentations et comparaisons incluant deux applications de traitement de l'image du monde réel sur cluster CPU-GPU
Since a decade, computing systems evolved to parallel and heterogeneous architectures. Composed of several nodes connected via a network and including heterogeneous processing units, clusters achieve high performances. To program these architectures, the user must rely on programming models such as MPI, OpenMP or CUDA. However, it is still difficult to conciliate productivity provided by abstracting the architectural specificities, and performances. In this thesis, we exploit the idea that a programming model specific to a particular domain of application can achieve these antagonist goals. In fact, by characterizing a family of application, it is possible to identify high level abstractions to efficiently model them. We propose two models specific to the implementation of signal and image processing applications on heterogeneous clusters. The first model is static. We enrich it with a task migration feature. The second model is dynamic, based on the StarPU runtime. Both models offer firstly a high level of abstraction by modeling image and signal applications as a data flow graph and secondly they efficiently exploit task, data and graph parallelisms. We validate these models with different implementations and comparisons including two real-world applications of images processing on a CPU-GPU cluster
APA, Harvard, Vancouver, ISO, and other styles
6

Costa, Kelton Augusto Pontara da. "Uma ferramenta para execução de algoritmos utilizando o modelo a fluxo de dados dinâmico em hardware reconfigurável para a arquitetura ChipCflow: módulo de conversão C em grafo a fluxo de dados." Universidade de São Paulo, 2009. http://www.teses.usp.br/teses/disponiveis/18/18152/tde-20082009-153150/.

Full text
Abstract:
O ChipCflow é o projeto de uma ferramenta para execução de algoritmos utilizando o modelo a fluxo de dados dinâmico em hardware reconfigurável. Tem como principal objetivo utilizar o modelo de arquitetura a fluxo de dados, associado ao conceito de arquiteturas reconfiguráveis, para acelerar programas de aplicação escritos em C. Essa aceleração vai acontecer nas partes mais intensas de processamento (exemplo: loops), através da execução direta em hardware, aproveitando ao máximo o paralelismo considerado natural do modelo a fluxo de dados. O módulo de conversão C em grafo a fluxo de dados, desenvolvido neste trabalho de doutoramento, é parte fundamental no desenvolvimento do projeto ChipCflow e se trata de um pré-compilador C que gera código VHDL para os operadores a fluxo de dados a partir de módulos do programa de aplicação escrito originalmente em C. É possível considerar como principal resultado dessa tese, a implementação de algoritmos a partir de uma linguagem C em grafo a fluxo de dados no modelo proposto no projeto ChipCflow, onde os operadores a fluxo de dados são os já tradicionalmente conhecidos, e até mesmo a forma de interconexão também, entretanto a forma de abordar essa implementação, em VHDL, e na forma de fluxo de dados dinâmico, torna o modelo proposto, tanto para o hardware como para o compilador, uma característica única existente até o momento.
ChipCflow is a tool for algorithms execution using a data dynamic flow in reconfigurable hardware. The main purpose of the work is to use the data flow architecture model, associated to the concept of reconfigurable architectures, to speed up C written applications. The program acceleration happens in the most intensive processing parts (example: loops), through direct hardware execution, using to advantage of the natural parallelism of the data flow model. The C conversion module in data flow graph is the basic part in the development of the ChipCflow project and the specific objective of the developed work. In this work we present detais of the C precompiler that generates VHDL code for the data flow operators modules of the written program of the original application in C. It is possible to consider as the main result of this thesis, the implementation of algorithms from a C language in the data flow graph model proposed in the project ChipCflow, where the operators to the data stream are typically already known, and even the way interconnection too, but how to approach the implementation in VHDL, and as a dynamic data flow, makes the proposed model for both the hardware and the compiler, a feature only available so far.
APA, Harvard, Vancouver, ISO, and other styles
7

Riachy, Léa. "Contribution à la commande d'un onduleur multiniveaux, destinée aux énergies renouvelables, en vue de réduire le déséquilibre dans les réseaux électriques." Thesis, Normandie, 2017. http://www.theses.fr/2017NORMR076/document.

Full text
Abstract:
Le travail de cette thèse apporte une contribution aux méthodes de réglage de la tension dans les réseaux électriques. Il s’agit de fournir au réseau la puissance active et surtout la puissance réactive nécessaire pour réguler la tension et aboutir à un système équilibré vue du côté source. Ces puissances sont extraites d’une source d’energie renouvelable : une attention particulière a été portée à l’énergie éolienne raccordée au réseau à travers la Machine Asynchrone à Double Alimentation (MADA) pilotée par des convertisseurs statiques. Le système de contrôle le plus répandu des éoliennes est basé principalement sur la technique d’extraction du maximum de puissance. Cependant, cette technique limite la mise en oeuvre deservices auxiliaires, telle que la participation des éoliennes au réglage de la tension dans le réseau électrique. Pour cela, une nouvelle méthode d’extraction du coefficient de puissance optimal, permettant d’améliorer la participation de la MADA à la régulation de la tension dans le réseau (compensation de la puissance réactive et du déséquilibre), a été développée. Le convertisseur multiniveaux à structure NPC (Neutral Point Clamped) raccordant l’énergie renouvelable au réseau a été étudié. La commande prédictive assurant simulatnément l’amélioration du facteur de puissance, l’équilibrage du réseau électrique et du bus continu du convertisseur NPC a été proposée. Ensuite, l’application de cette commande prédictive a été elargie en lui attribuant plusieurs objectifs : amélioration du facteur de puissance avec équilibrage du réseau, équilibrage du bus continu, minimisation des pertes par commutation et réduction de la tension de mode commun. La minimisation des pertes a été obtenue en proposant une nouvelle stratégie qui consiste à exploiter les datasheets constructeurs donnant l’évolution de l’énergie dissipée durant la commutation en fonction du courant. Ces courbes expérimentales ont été transformées en modèlesmathématiques implémentés dans la commande prédictive. Les résultats de simulation et expérimentaux sont présentés pour évaluer les performances de la méthode proposée
The work in this research thesis presents a contribution to voltage regulation in electrical networks. By considering adequate active and reactive powers injection into the grid, voltage control and load balancing are provided. These powers are generated from a grid connected renewable energy conversion system : a special attention was paid to the Wind Energy ConversionSystem (WECS) based on Doubly-Fed Induction Generator (DFIG).The typical control strategy for WECS is the maximum power coefficient tracking method. However, this method limits desirable ancillary power services, such as the participation of wind turbines in voltage regulation in the power grid. Therefore, a new method that derives the optimal power coefficient enhancing the participation of WTS in voltage regulation in the network (reactive and unbalanced power compensation), has been developed. The multilevel NPC (Neutral Point Clamped) converter, used for grid interface connection of renewable energy sources systems, has been studied. A predictive control method for the three-level NPC converter, capable of simultaneously compensating the problems of : DC link capacitors voltage balancing, load balancing and power factor correction in the power system, has been proposed. Then, the application of this predictive control was extended to simultaneously achieve multiple objectives: load balancing with power factor correction in the network, DC link capacitors voltage balancing, switching losses minimization and common mode voltage reduction. The switching losses minimization was obtained by proposing a new strategy which consists on exploiting the manufacturer datasheets that gives the evolution of the switching loss energy in function of the circulating current. The experimental curves of the datasheet are expressed in a mathematical model implemented in the predictive control. Simulation and experimental results are presented to evaluate the performance of the proposed method
APA, Harvard, Vancouver, ISO, and other styles
8

Massoud, Chadi. "Evaluation de la filtration glomérulaire par IRM." Thesis, Montpellier 2, 2010. http://www.theses.fr/2010MON20037.

Full text
Abstract:
Cette étude cherche à évaluer le Débit de la Filtration Glomérulaire (DFG) dans le rein humain par IRM. L'estimation de ce paramètre quantitatif nécessite le suivi de la cinétique intrarénale de Gd après son injection en bolus. Pour atteindre cet objectif, nous avons développé sous IDEA Siemens une séquence SR-FLASH strictement pondérée en T1 capable de suivre en dynamique l'évolution du signal RMN après l'injection d'un bolus de produit de contraste. Cette séquence possède un codage de phase centré permettant de déterminer le contraste au début de la période d'acquisition de l'image. Nous avons également mis en oeuvre une séquence d'inversion IR-FLASH (avec codage de phase centré) permettant la mesure de la relaxation longitudinale en l'absence de produit de contraste, ce paramètre étant indispensable à la conversion de l'intensité du signal en concentration. Sachant que la relation entre l'intensité du signal RMN et la concentration de Gd n'est pas linéaire, nous avons proposé deux méthodes originales et malgré tout rapides et robustes pour convertir le signal RMN en concentration locale de Gd. Ceci nous a permis d'évaluer l'évolution de la concentration dans les deux reins et dans l'aorte au cours des premiers passages du produit. L'ajustement des ces mesures de concentration sur les équations décrivant une modélisation bicompartimentale de la fonction rénale a permis de calculer le DFG de chaque rein dans une population de cinq sujets possédant un fonctionnement rénal normal
This study seeks to assess the Glomerular Filtration Rate (GFR) in the human kidney by MRI. To quantitatively estimate this parameter requires monitoring of the intrarenal kinetics of Gd after its bolus injection. To achieve this goal, we have developed under IDEA Siemens a SR-FLASH T1-weighted MRI sequence which can follow dynamic NMR signal changes after a bolus injection of Gd. This sequence has a centric phase-encoding scheme, and thus the image contrast was determined at the beginning of the acquisition period. Subsequently, we have implemented an IR-FLASH (with centric phase-encoding scheme) sequence to measure the longitudinal relaxation time in the absence of any injection of Gd ; this parameter is required to convert NMR signal intensities into Gd concentrations. knowing that the relation between the NMR signal intensities and the Gd concentrations is not linear, we have proposed two novel methods and yet fast and robust for conversion of the NMR signal intensities into local Gd concentration. This allowed us to estimate the temporal evolution of Gd concentrations in both kidneys and aorta. The fit of these concentrations measurements by a two-compartments model describing the function of the kidney allowed us to calculate the GFR of each kidney in a population of five subjects with normal renal function
APA, Harvard, Vancouver, ISO, and other styles
9

Adolfssson, Alexander, and Marie Åström. "Development Finance Institutions’ Effect on The Fund Manager’s Investment Decisions : Balancing Financial Performance Goals and Development Impact Objectives." Thesis, Umeå universitet, Företagsekonomi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-124744.

Full text
Abstract:
Development Finance Institutions (DFIs) have played a crucial role in moving socially responsibility considerations up on the private equity industry’s agenda. DFIs add a development impact criterion to traditional financial performance goals in the investment industry and play a catalytic role by mobilizing other investors. The gap in research regarding DFIs implications and significance in the investment community from a SRI perspective is evident. The development impact objective introduced by the DFIs is examined to understand its effects on fund managers’ decision-making and if it exists a trade-off between this objective and financial performance. An understanding of how DFIs control fund managers to act in accordance to their objective as well as how they determine compensation schemes to incentivize them to pursue high return on investments, is discussed in relation to the agency theory. Furthermore, stakeholder/shareholder consideration is examined in relation to the subject. The aim of this study is to examine how the behavior of fund managers is affected by the involvement of a DFI investor and try to add to the understanding of their significance as institutional investors in developing markets. Previous studies have been more focused on determining the financial performance of socially responsible investments by using very similar quantitative data collection methods. This thesis undertakes an in-depth approach with the purpose to understand the fund manager’s drives as well as how a DFI involvement affects the behavior and decision-making process.   This thesis undertook a qualitative research strategy and semi-structured interviews were used as the tool to understand the fund managers’ personals beliefs and perceptions of how the relationship with DFIs affect them. The selection criteria for the fund managers was that they needed to work in a fund in which a DFIs has invested. We also included DFI investors in order to understand their point of view. The interview was recorded, transcribed and later divided into themes in accordance with the thematic approach, following six steps. Our findings show that Development Finance Institutions plays an important role in emerging markets and affect fund manager behavior to a certain extent. They did not perceive a trade-off between financial performance goals and development impact objectives. We conclude that DFIs increase fund manager focus on ESG/SEE elements in the investment process. DFIs requirements and reporting obligations is used as a tool to ensure that the fund manager act in accordance to DFI objective. The fund managers were neither willing to sacrifice commercial return in favor of development impact. Lastly, the interest among the DFIs and commercial investors is fairly similar, hence reducing the conflict of interest between investors.
APA, Harvard, Vancouver, ISO, and other styles
10

Adabi, Firouzjaee Jafar. "Remediation strategies of shaft and common mode voltages in adjustable speed drive systems." Thesis, Queensland University of Technology, 2010. https://eprints.qut.edu.au/39293/1/Jafar_Adabi_Firouzjaeel_Thesis.pdf.

Full text
Abstract:
AC motors are largely used in a wide range of modern systems, from household appliances to automated industry applications such as: ventilations systems, fans, pumps, conveyors and machine tool drives. Inverters are widely used in industrial and commercial applications due to the growing need for speed control in ASD systems. Fast switching transients and the common mode voltage, in interaction with parasitic capacitive couplings, may cause many unwanted problems in the ASD applications. These include shaft voltage and leakage currents. One of the inherent characteristics of Pulse Width Modulation (PWM) techniques is the generation of the common mode voltage, which is defined as the voltage between the electrical neutral of the inverter output and the ground. Shaft voltage can cause bearing currents when it exceeds the amount of breakdown voltage level of the thin lubricant film between the inner and outer rings of the bearing. This phenomenon is the main reason for early bearing failures. A rapid development in power switches technology has lead to a drastic decrement of switching rise and fall times. Because there is considerable capacitance between the stator windings and the frame, there can be a significant capacitive current (ground current escaping to earth through stray capacitors inside a motor) if the common mode voltage has high frequency components. This current leads to noises and Electromagnetic Interferences (EMI) issues in motor drive systems. These problems have been dealt with using a variety of methods which have been reported in the literature. However, cost and maintenance issues have prevented these methods from being widely accepted. Extra cost or rating of the inverter switches is usually the price to pay for such approaches. Thus, the determination of cost-effective techniques for shaft and common mode voltage reduction in ASD systems, with the focus on the first step of the design process, is the targeted scope of this thesis. An introduction to this research – including a description of the research problem, the literature review and an account of the research progress linking the research papers – is presented in Chapter 1. Electrical power generation from renewable energy sources, such as wind energy systems, has become a crucial issue because of environmental problems and a predicted future shortage of traditional energy sources. Thus, Chapter 2 focuses on the shaft voltage analysis of stator-fed induction generators (IG) and Doubly Fed Induction Generators DFIGs in wind turbine applications. This shaft voltage analysis includes: topologies, high frequency modelling, calculation and mitigation techniques. A back-to-back AC-DC-AC converter is investigated in terms of shaft voltage generation in a DFIG. Different topologies of LC filter placement are analysed in an effort to eliminate the shaft voltage. Different capacitive couplings exist in the motor/generator structure and any change in design parameters affects the capacitive couplings. Thus, an appropriate design for AC motors should lead to the smallest possible shaft voltage. Calculation of the shaft voltage based on different capacitive couplings, and an investigation of the effects of different design parameters are discussed in Chapter 3. This is achieved through 2-D and 3-D finite element simulation and experimental analysis. End-winding parameters of the motor are also effective factors in the calculation of the shaft voltage and have not been taken into account in previous reported studies. Calculation of the end-winding capacitances is rather complex because of the diversity of end winding shapes and the complexity of their geometry. A comprehensive analysis of these capacitances has been carried out with 3-D finite element simulations and experimental studies to determine their effective design parameters. These are documented in Chapter 4. Results of this analysis show that, by choosing appropriate design parameters, it is possible to decrease the shaft voltage and resultant bearing current in the primary stage of generator/motor design without using any additional active and passive filter-based techniques. The common mode voltage is defined by a switching pattern and, by using the appropriate pattern; the common mode voltage level can be controlled. Therefore, any PWM pattern which eliminates or minimizes the common mode voltage will be an effective shaft voltage reduction technique. Thus, common mode voltage reduction of a three-phase AC motor supplied with a single-phase diode rectifier is the focus of Chapter 5. The proposed strategy is mainly based on proper utilization of the zero vectors. Multilevel inverters are also used in ASD systems which have more voltage levels and switching states, and can provide more possibilities to reduce common mode voltage. A description of common mode voltage of multilevel inverters is investigated in Chapter 6. Chapter 7 investigates the elimination techniques of the shaft voltage in a DFIG based on the methods presented in the literature by the use of simulation results. However, it could be shown that every solution to reduce the shaft voltage in DFIG systems has its own characteristics, and these have to be taken into account in determining the most effective strategy. Calculation of the capacitive coupling and electric fields between the outer and inner races and the balls at different motor speeds in symmetrical and asymmetrical shaft and balls positions is discussed in Chapter 8. The analysis is carried out using finite element simulations to determine the conditions which will increase the probability of high rates of bearing failure due to current discharges through the balls and races.
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "DFIG MODEL"

1

Joint CNRS-DFG Workshop on Numerical Flow Simulation (9th 2002 Nice, France). Numerical flow simulation III: CNRS-DFG collaborative research programme, results 2000-2002. Edited by Hirschel Ernst-Heinrich. Berlin: Springer, 2003.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Ernst-Heinrich, Hirschel, Deutsche Forschungsgemeinschaft, Centre national de la recherche scientifique (France), and CNRS-DFG Colloquium on Numerical Flow Simulation (8th : 1999 : Berlin, Germany), eds. Numerical flow simulation II: CNRS-DFG collaborative research programme, results 1998-2000. Berlin: Springer, 2001.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Foppe, K. Abschlussbericht, DFG-Projekt Pe 187/9 Geotechnisches Informationssystem. Hannover: [Universität Hannover, 1998.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Hirschel, Ernst-Heinrich. Numerical flow simulation II: CNRS-DFG collaborative research programme results 1998-2000. Berlin: Springer, 2001.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Kommission, Deutsche Geodätische, ed. Physically consistent system model for the study of the Earth's rotation, surface deformation and gravity field parameters: Scientific results of the DFG project. München: Verlag der Bayerischen Akademie der Wissenschaften, 2009.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Lyndon B. Johnson Space Center. Systems Engineering Division. and Chrysler Corporation. Electronics Products Division. Michoud Engineering Office. Data Management Services., eds. Results of aeroheating DFI and ET design-data test on a 0.0175-scale model 60-OTS conducted in the Von Karman gas dynamics facility (VKF) 40-inch supersonic and the 50-inch hypersonic wind tunnels A&C (IH-97A/B/C). Houston, Tex: Systems Engineering Division, Johnson Space Center, National Aeronautics and Space Administration, 1985.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Schulz, Horst D., and Georg Teutsch. DFG Geochemical Processes: Conceptual Models for Reactive Transport in Soil and Groundwater. Wiley & Sons, Limited, John, 2007.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Röding, Carolin, Katerina Harvati, Matteo Scardovelli, Solange Rigard, Michela Leonardi, Andaine Seguin-Orlando, Mark Hubbe, and Andrej Evteev. Ancient Connections in Eurasia. Edited by Hugo Reyes-Centeno and Katerina Harvati. Kerns Verlag, 2021. http://dx.doi.org/10.51315/9783935751377.

Full text
Abstract:
Models pertaining to the antiquity and continuity of Eurasian human populations and their cultural traditions have been revised in recent years as a result of novel inter-disciplinary research. In this third installment of the DFG Center for Advanced Studies Series, experts provide new field case studies, reviews, and original research on bio-cultural connections in Eurasia since the Paleolithic.
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "DFIG MODEL"

1

Fu, Ho-Ling, and Huynh Thanh Thien. "Modeling a Wind Turbine System Using DFIG and Realization of Current Control on the Model with Fuzzy Logic Controller." In AETA 2013: Recent Advances in Electrical Engineering and Related Sciences, 85–92. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-41968-3_10.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Cong, Cuong Nguyen, Ricardo Rodriguez-Jorge, Nghien Nguyen Ba, Chuong Trinh Trong, and Nghia Nguyen Anh. "Design of Optimal PI Controllers Using the Chemical Reaction Optimization Algorithm for Indirect Power Control of a DFIG Model with MPPT." In Advances in Intelligent Systems and Computing, 1250–60. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-44038-1_114.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Abu-Siada, Ahmed, Mohammad A. S. Masoum, Yasser Alharbi, Farhad Shahnia, and A. M. Shiddiq Yunus. "Applications of Unified Power Flow Controller in Wind Energy Conversion System." In Recent Advances in Renewable Energy, 17–48. UAE: Bentham Science Publishers Ltd., 2017. http://dx.doi.org/10.2174/9781681085425117020003.

Full text
Abstract:
Unified power flow controller (UPFC) is one of the Flexible ac Transmission System (FACTS) devices that possess the ability of modulating both active and reactive power at the point of common coupling in four quadrant operational modes. This chapter illustrates UPFC topology, controllers with some case studies for various applications of UPFC in the DFIG-based WECS. New applications for UPFC are proposed to improve the overall performance of a DFIG-based WECS during voltage sag and voltage swell events at the grid side.
APA, Harvard, Vancouver, ISO, and other styles
4

van der Aalst, Wil M. P. "Foundations of Process Discovery." In Lecture Notes in Business Information Processing, 37–75. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-08848-3_2.

Full text
Abstract:
AbstractProcess discovery is probably the most interesting, but also most challenging, process mining task. The goal is to take an event log containing example behaviors and create a process model that adequately describes the underlying process. This chapter introduces the baseline approach used in most commercial process mining tools. A simplified event log is used to create a so-called Directly-Follows Graph (DFG). This baseline is used to explain the challenges one faces when trying to discover a process model. After introducing DFG discovery, we focus on techniques that are able to discover models allowing for concurrency (e.g., Petri nets, process trees, and BPMN models). The chapter distinguishes two types of approaches able to discover such models: (1) bottom-up process discovery and (2) top-down process discovery. The Alpha algorithm is presented as an example of a bottom-up technique. The approach has many limitations, but nicely introduces the idea of discovering local constraints. The basic inductive mining algorithm is presented as an example of a top-down technique. This approach, combined with frequency-based filtering, works well on most event logs. These example algorithms are used to illustrate the foundations of process discovery.
APA, Harvard, Vancouver, ISO, and other styles
5

Shah, Ankit, and Axaykumar Mehta. "Sliding Mode Direct Power Control of a Grid-Connected DFIG Using an Extended State Observer." In Emerging Trends in Sliding Mode Control, 325–49. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-8613-2_14.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Mishra, Y., S. Mishra, Fangxing Li, and Z. Y. Dong. "Eigenvalue Analysis of a DFIG Based Wind Power System under Different Modes of Operations." In Green Energy and Technology, 191–213. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-13250-6_8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Rueda, José Luis, Abdul W. Korai, Jaime C. Cepeda, István Erlich, and Francisco M. Gonzalez-Longatt. "Implementation of Simplified Models of DFIG-Based Wind Turbines for RMS-Type Simulation in DIgSILENT PowerFactory." In PowerFactory Applications for Power System Analysis, 197–220. Cham: Springer International Publishing, 2014. http://dx.doi.org/10.1007/978-3-319-12958-7_9.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Du, Wenjuan, Haifeng Wang, and Siqi Bu. "Modal Analysis of Small-Signal Angular Stability of a Power System Affected by Grid-Connected DFIG." In Small-Signal Stability Analysis of Power Systems Integrated with Variable Speed Wind Generators, 97–146. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-94168-4_4.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

He, Xin, Shengnan Li, Junpeng Li, Xian Meng, Yong Cheng, Yongchang Zhang, and Tao Jiang. "Robust Predictive Rotor Current Control of DFIGs Based on an Adaptive Ultra-local Model." In Conference Proceedings of 2022 2nd International Joint Conference on Energy, Electrical and Power Engineering, 129–37. Singapore: Springer Nature Singapore, 2023. http://dx.doi.org/10.1007/978-981-99-4334-0_16.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Audia, Camilla, Emma Visman, Gino Fox, Emmah Mwangi, Mary Kilavi, Mark Arango, Sonja Ayeb-Karlsson, and Dominic Kniveton. "Decision-Making Heuristics for Managing Climate-Related Risks: Introducing Equity to the FREE Framework." In Climate Risk in Africa, 57–76. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-61160-6_4.

Full text
Abstract:
AbstractManaging climate-related risks is clouded in differing levels of uncertainty that are magnified when trying to understand their potential impacts on socio-ecological systems. The ‘cascade of uncertainty’ is particularly apparent in Africa where socio-ecological data are sparse, and the development and validation of impact models are at varying stages. In this context, using heuristics may serve as an effective way for policy makers to incorporate climate change knowledge into decision-making. Previous scholarship has identified the principles of Flexibility, Robustness and Economic low/no regrets in decision-making under uncertainty. In this chapter, we first make the case for adding Equity to these heuristics, where equity involves ensuring that reducing the climate change risk for one cohort of society does not result in its increase for another. Second, we describe how these principles have been applied under two DFID/NERC funded projects: ForPAc and AMMA-2050 through the use of Participatory Impact Pathways Analysis tools.
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "DFIG MODEL"

1

Gatavi, Ehsan, and Amir H. Shirdel. "Model Predictive Control of DFIG-Based Wind Turbine." In ASME 2014 Dynamic Systems and Control Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/dscc2014-5935.

Full text
Abstract:
This paper presents a centralized multivariable control strategy for the control of the DFIG wind turbine. Model of one-mass wind turbine with DFIG is represented by a third-order model. Model predictive control is applied in order to compensate inaccuracies and measurement noise. The optimization problem is recast as a Quadratic Program (QP) which is highly robust and efficient. In order to bring the problematic voltages as closely as possible to the desired values, multi-step optimization is introduced. The effectiveness of the proposed algorithm is demonstrated for a variable speed wind turbine.
APA, Harvard, Vancouver, ISO, and other styles
2

Chen, Qiong-zhong, and Olivier Bru¨ls. "Integrated Power Control Analysis of DFIG Wind Turbines Considering Structural Flexibility." In ASME 2011 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2011. http://dx.doi.org/10.1115/detc2011-48253.

Full text
Abstract:
Doubly-fed induction generators (DFIGs) are commonly used in variable-speed wind turbines for more power extraction. Unlike previous research on DFIG wind turbines, which typically uses an equivalent lumped mass model of the drive train dynamics, but does not include detailed aerodynamic/mechanical representations, this paper investigates on the modelling and control of DFIG wind turbines by following a systematic approach based on a flexible multibody simulation software. The wind turbine structure, generator and control subsystem models are modularly developed for the S4WT package (Samcef for Wind Turbines), which is a user interface for the analysis of wind turbines. An extension of the finite element method is available in the flexible multibody dynamics solver, for the representation of the non-mechanical components, i.e., the generator and the control system, so that the coupled mechatronic system is simulated in a strongly coupled way. This integrated approach is less intricate and more robust than approaches based on an external DLL or co-simulation methods. The objective of this work is to analyze the control-generator-structure interactions in a wind turbine system. The power optimization control is elaborated in detail. A 2MW DFIG wind turbine prototype model is presented for validation. Dynamic analysis including the control effects and the influence of the structural flexibility is provided in an overall range.
APA, Harvard, Vancouver, ISO, and other styles
3

Kaneko, A., N. Hara, and K. Konishi. "Model predictive control of DFIG-based wind turbines." In 2012 American Control Conference - ACC 2012. IEEE, 2012. http://dx.doi.org/10.1109/acc.2012.6314883.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Kayikci, M., and J. V. Milanovic. "DFIG modelling and the relevance of model simplification." In 18th International Conference and Exhibition on Electricity Distribution (CIRED 2005). IEE, 2005. http://dx.doi.org/10.1049/cp:20051271.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Shih-Yu Yang, Yuan-Kang Wu, Huei-Jeng Lin, and Wei-Jen Lee. "Integrated mechanical and electrical DFIG wind turbine model development." In 2013 IEEE Industry Applications Society Annual Meeting. IEEE, 2013. http://dx.doi.org/10.1109/ias.2013.6682471.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Chowdhury, M. A., N. Hosseinzadeh, M. M. Billah, and S. A. Haque. "Dynamic DFIG wind farm model with an aggregation technique." In Computer Engineering (ICECE). IEEE, 2010. http://dx.doi.org/10.1109/icelce.2010.5700695.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Deshpande, Anjali V., and V. A. Kulkarni. "Simplified Model of DFIG in Wind Integrated Power System." In 2019 3rd International Conference on Computing Methodologies and Communication (ICCMC). IEEE, 2019. http://dx.doi.org/10.1109/iccmc.2019.8819670.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Hammami, Asma, Imen Saidi, and Dhaou Soudani. "Control of DFIG-variable wind turbine with internal model controller." In 2019 International Conference on Advanced Systems and Emergent Technologies (IC_ASET). IEEE, 2019. http://dx.doi.org/10.1109/aset.2019.8870977.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Blasch, Erik. "One decade of the Data Fusion Information Group (DFIG) model." In SPIE Sensing Technology + Applications, edited by Barbara D. Broome, Timothy P. Hanratty, David L. Hall, and James Llinas. SPIE, 2015. http://dx.doi.org/10.1117/12.2176934.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Honrubia-Escribano, A., E. Gomez-Lazaro, A. Vigueras-Rodriguez, A. Molina-Garcia, J. A. Fuentes, and E. Muljadi. "Assessment of DFIG simplified model parameters using field test data." In 2012 IEEE Power Electronics and Machines in Wind Applications (PEMWA). IEEE, 2012. http://dx.doi.org/10.1109/pemwa.2012.6316374.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "DFIG MODEL"

1

Baloch, Imdad, Tom Kaye, Saalim Koomar, and Chris McBurnie. Pakistan Topic Brief: Providing Distance Learning to Hard-to-reach Children. EdTech Hub, June 2020. http://dx.doi.org/10.53832/edtechhub.0026.

Full text
Abstract:
The COVID-19 pandemic has resulted in mass school closures across the world. It is expected that the closures in low- and -middle-income countries (LMICs) will have long-term negative consequences on education and also on broader development outcomes. Countries face a number of obstacles to effectively delivering alternative forms of education. Obstacles include limited experience in facing such challenges, limited teacher digital and pedagogical capacity, and infrastructure constraints related to power and connectivity. Furthermore, inequalities in learning outcomes are expected to widen within LMICs due to the challenges of implementing alternative modes of education in remote, rural or marginalised communities. It is expected that the most marginalised children will feel the most substantial negative impacts on their learning outcomes. Educational technology (EdTech) has been identified as a possible solution to address the acute impact of school closures through its potential to provide distance education. In this light, the DFID Pakistan team requested the EdTech Hub develop a topic brief exploring the use of EdTech to support distance learning in Pakistan. Specifically, the team requested the brief explore ways to provide distance education to children in remote rural areas and urban slums. The DFID team also requested that the EdTech Hub explore the different needs of those who have previously been to school in comparison to those who have never enrolled, with reference to EdTech solutions. In order to address these questions, this brief begins with an overview of the Pakistan education landscape. The second section of the brief explores how four modes of alternative education — TV, interactive radio instruction, mobile phones and online learning — can be used to provide alternative education to marginalised groups in Pakistan. Multimodal distance-learning approaches offer the best means of providing education to heterogeneous, hard-to-reach groups. Identifying various tools that can be deployed to meet the needs of specific population segments is an important part of developing a robust distance-learning approach. With this in mind, this section highlights examples of tools that could be used in Pakistan to support a multimodal approach that reaches the most hard-to-reach learners. The third and final section synthesises the article’s findings, presenting recommendations to inform Pakistan’s COVID-19 education response.<br> <br> This topic brief is available on Google Docs.
APA, Harvard, Vancouver, ISO, and other styles
2

Herbert, Siân. Donor Support to Electoral Cycles. Institute of Development Studies (IDS), April 2021. http://dx.doi.org/10.19088/k4d.2021.043.

Full text
Abstract:
This rapid literature review explains the stages of an election cycle, and how donors provide support to electoral cycles. It draws mainly on policy guidance websites and papers due to the questions of this review and the level of analysis taken (global-level, donor-level). It focuses on publications from the last five years, and/or current/forthcoming donor strategies. The electoral cycle and its stages are well-established policy concepts for which there is widespread acceptance and use. Donor support to electoral cycles (through electoral assistance and electoral observation) is extremely widespread, and the dominant donors in this area are the multilateral organisations like the United Nations (UN) and the European Union (EU), and also the United States (US). While almost all bilateral donors also carry out some work in this area, “almost all major electoral support programmes are provided jointly with international partners” (DFID, 2014, p.5). Bilateral donors may provide broader support to democratic governance initiatives, which may not be framed as electoral assistance, but may contribute to the wider enabling environment. All of the donors reviewed in this query emphasise that their programmes are designed according to the local context and needs, and thus, beyond the big actors - EU, UN and US, there is little overarching information on what the donors do in this area. While there is a significant literature base in the broad area of electoral support, it tends to be focussed at the country, programme, or thematic, level, rather than at the global, or donor, level taken by this paper. There was a peak in global-level publications on this subject around 2006, the year the electoral cycle model was published by the European Commission, International Institute for Democracy and Electoral Assistance (International IDEA), and United Nations Development Programme (UNDP). This review concludes by providing examples of the electoral assistance work carried out by five donors (UN, EU, US, UK and Germany).
APA, Harvard, Vancouver, ISO, and other styles
3

Industria 4.0 en las PYMES de Gipuzkoa. Universidad de Deusto, 2019. http://dx.doi.org/10.18543/bcff5984.

Full text
Abstract:
El informe elabora un diagnóstico de la situación de las pymes industriales guipuzcoanas ante el paradigma de la Industria 4.0. El diseño metodológico y la recolección de datos se basa en un proceso de investigación-acción con la participación de tres actores: Diputación Foral de Gipuzkoa (DFG), diez agencias de desarrollo comarcal, y Orkestra-Instituto Vasco de Competitividad. El segmento empresarial objetivo es el de pymes industriales guipuzcoanas entre 20 y 100 personas. Las principales actividades realizadas son: a) el desarrollo de talleres de investigación acción que permitieron consensuar una definición del concepto de Industria 4.0, y diseñar una metodología base para diagnosticar la situación de las empresas a través de una encuesta, y b) la compilación, análisis, e interpretación compartida de la información obtenida. Entre las conclusiones obtenidas se destacan: -La generación de aprendizaje, visión compartida, y nuevo modelo de gobernanza, desarrollado en el marco del Laboratorio de Desarrollo Territorial, entre los actores del proceso y que son efectos intrínsecamente vinculados a procesos de investigación-acción. -La categorización de empresas en relación con la implementación de la Industria 4.0 en función a diferencias de tamaño, sector de actividad, y estado de planificación. Asimismo, dentro de cada segmento existen situaciones particulares que demandan atender a las heterogeneidades y complejidades. -La necesidad de continuar profundizando en formas y/o nuevos canales de relación entre el sector público y privado como requerimiento de los actores del territorio para avanzar en la cantidad y calidad de información y/u otras actividades promovidas desde la política pública. -Finalmente, aunque no menos importante, un reto esencial para la implementación y adaptación al paradigma de la Industria 4.0 es la demanda por adecuar las capacidades de las personas trabajadoras ante este fenómeno.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography