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Full-Text Articles in Engineering
Modeling And Analysis Of A 12kw Solar-Wind Hybrid Renewable Energy System, Ekaterina Muravleva
Modeling And Analysis Of A 12kw Solar-Wind Hybrid Renewable Energy System, Ekaterina Muravleva
Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research
The increase in rate of depletion of natural resources in the last decade as well as the increased global focus on climate change has made the transition to renewable resources of energy a priority for various countries and organizations across the globe. The sporadic nature of energy generated by photovoltaic systems and wind energy conversion systems has led to an increased utilization of more reliable hybrid renewable energy systems. A combination of both solar and wind energy-based power generations systems reduces the impact of seasonal variation on the amount of power generated and therefore, can be used under varying weather …
Low Latency Bearing Fault Detection Of Direct-Drive Wind Turbines Using Stator Current, Samrat Nath, Jingxian Wu, Yue Zhao, Wei Qiao
Low Latency Bearing Fault Detection Of Direct-Drive Wind Turbines Using Stator Current, Samrat Nath, Jingxian Wu, Yue Zhao, Wei Qiao
Department of Electrical and Computer Engineering: Faculty Publications
Low latency change detection aims to minimize the detection delay of an abrupt change in probability distributions of a random process, subject to certain performance constraints such as the probability of false alarm (PFA). In this paper, we study the low latency detection of bearing faults of direct-drive wind turbines (WT), by analyzing the statistical behaviors of stator currents generated by the WT in real-time. It is discovered that the presence of fault will affect the statistical distribution of WT stator current amplitude at certain frequencies. Since the signature of a fault can appear in one of the multiple possible …
Current-Based Fault Detection For Wind Turbine Systems Via Hilbert-Huang Transform, Dingguo Lu, Wei Qiao, Xiang Gong, Liyan Qu
Current-Based Fault Detection For Wind Turbine Systems Via Hilbert-Huang Transform, Dingguo Lu, Wei Qiao, Xiang Gong, Liyan Qu
Department of Electrical and Computer Engineering: Faculty Publications
Mechanical failures of wind turbines represent a significant cost in both repairs and downtime. Detecting incipient faults of wind turbine components permits maintenance to be scheduled and failed parts to be repaired or replaced before causing failures of other components or catastrophic failure of the system. This paper proposes a Hilbert-Huang transform (HHT)-based algorithm to effectively extract fault signatures in generator current signals for wind turbine fault diagnosis by using the HHT’s capability of accurately representing the instantaneous amplitude and frequency of nonlinear and nonstationary signals. A phase-lock-loop (PLL) method is integrated to estimate wind turbine rotating speed, which is …
Online Nonintrusive Condition Monitoring And Fault Detection For Wind Turbines, Xiang Gong
Online Nonintrusive Condition Monitoring And Fault Detection For Wind Turbines, Xiang Gong
Department of Electrical and Computer Engineering: Dissertations, Theses, and Student Research
The goal of this dissertation research is to develop online nonintrusive condition monitoring and fault detection methods for wind turbine generators (WTGs). The proposed methods use only the current measurements that have already been used by the control and protection systems of WTGs; no additional sensors or data acquisition devices are needed. Current-based condition monitoring and fault detection techniques have great economic benefits and the potential to be adopted by the wind energy industry. However, there are challenges in using current measurements for wind turbine condition monitoring and fault detection. First, it is a challenge to extract WTG fault signatures …
Prestressed Concrete Wind Turbine Supporting System, Ibrahim Lotfy
Prestressed Concrete Wind Turbine Supporting System, Ibrahim Lotfy
Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research
Wind energy is one of the most commercially developed and quickly evolving renewable energy technologies worldwide. Wind turbines are commonly supported on tubular steel towers. As the turbines are growing and the towers are elevating, an increase in structural strength and stiffness is required to withstand the applied forces. Recent studies established concrete as a more economic and durable alternative to steel especially when the tower height exceed 240ft. Presently, concrete towers are not common due to their perceived heavy weight and assembly complexity. One of the systems that have been mentioned in the literature consists of precast rings that …
Wind Speed And Rotor Position Sensorless Control For Direct-Drive Pmg Wind Turbines, Wei Qiao, Xu Yang, Xiang Gong
Wind Speed And Rotor Position Sensorless Control For Direct-Drive Pmg Wind Turbines, Wei Qiao, Xu Yang, Xiang Gong
Department of Electrical and Computer Engineering: Faculty Publications
This paper proposes a wind speed and rotor position sensorless control for wind turbines directly driving permanent magnetic generators (PMGs). A sliding-mode observer is designed to estimate the rotor position of the PMG by using the measured stator currents and the commanded stator voltages obtained from the control scheme of the machine-side converter of the PMG wind turbine. The rotor speed of the PMG (i.e., the turbine shaft speed) is estimated from its back electromotive force using a model adaptive reference system observer. Based on the measured output electrical power and estimated rotor speed of the PMG, the mechanical power …
Constant Power Control Of Dfig Wind Turbines With Supercapacitor Energy Storage, Liyan Qu, Wei Qiao
Constant Power Control Of Dfig Wind Turbines With Supercapacitor Energy Storage, Liyan Qu, Wei Qiao
Department of Electrical and Computer Engineering: Faculty Publications
With the increasing penetration of wind power into electric power grids, energy storage devices will be required to dynamically match the intermittency of wind energy. This paper proposes a novel two-layer constant power control scheme for a wind farm equipped with doubly fed induction generator (DFIG) wind turbines. Each DFIG wind turbine is equipped with a super-capacitor energy storage system (ESS) and is controlled by the low-layer wind turbine generator (WTG) controllers and coordinated by a high-layer wind farm supervisory controller (WFSC). The WFSC generates the active power references for the low-layer WTG controllers according to the active power demand …
Risk-Based Failure Mode And Effect Analysis For Wind Turbines (Rb-Fmea), Salman Kahrobaee, Sohrab Asgarpoor
Risk-Based Failure Mode And Effect Analysis For Wind Turbines (Rb-Fmea), Salman Kahrobaee, Sohrab Asgarpoor
Department of Electrical and Computer Engineering: Faculty Publications
Failure Mode and Effect Analysis (FMEA) has already been used as a qualitative measure for identifying failure modes and causes, in order to mitigate the effects of failure in different sectors of power systems. This paper presents a quantitative approach called Risk-Based-FMEA, based on the failure probabilities and incurred failure costs instead of rating scales. As a case study, this approach has been applied to a direct drive wind turbine. The results show that the definition of failure modes priorities based on their contribution to the total failure cost of the wind turbine is more realistic and practical than the …
Computational Intelligence For Control Of Wind Turbine Generators, Wei Qiao, Jiaqi Liang, Ganesh K. Venayagamoorthy, Ronald Harley
Computational Intelligence For Control Of Wind Turbine Generators, Wei Qiao, Jiaqi Liang, Ganesh K. Venayagamoorthy, Ronald Harley
Department of Electrical and Computer Engineering: Faculty Publications
This paper summarizes past and ongoing research in the area of the application of computational intelligence (CI) for control of wind turbine generators (WTGs). Several intelligent design approaches and control strategies, including optimal design of WTG controllers using particle swarm optimization (PSO) and mean-variance optimization (MVO) algorithms and adaptive critic design-based coordinated optimal adaptive control for wind plants and shunt FACTS devices, are presented for dynamic performance and fault ride-through enhancement of WTGs and the associated power grid. The effectiveness of these intelligent design approaches and control strategies are demonstrated by nonreal- and real-time simulations in PSCAD/EMTDC and RSCAD/RTDS, respectively.
Dynamic Modeling And Control Of Doubly Fed Induction Generators Driven By Wind Turbines, Wei Qiao
Dynamic Modeling And Control Of Doubly Fed Induction Generators Driven By Wind Turbines, Wei Qiao
Department of Electrical and Computer Engineering: Faculty Publications
Two different models are presented and developed in PSCAD/EMTDC to represent a variable-speed wind turbine equipped with a doubly fed induction generator (DFIG). One is the most detailed switching-level (SL) model. The other is a simplified fundamental-frequency (FF) model. The effect of different shaft system representations on the dynamic behavior of the wind turbine generator (WTG) system and the issue of damping low-frequency torsional oscillations are investigated. Dynamic and transient simulation studies are carried out to compare two models with different shaft system representations. Results show that the FF model is sufficient while the lumpedmass shaft model is insufficient to …