Electrotechnique
Detection of Broken Rotor Bar Fault in Squirrel Cage Induction Motor using Wavelet Packet Analysis
The fault of broken rotor bars in a three-phase induction motor is diagnosed by using the wavelet Packet analysis. In this paper Daubechies wavelet is selected as the wavelet base and the wavelet coefficient is obtained from the wavelet transform of current signal of the faulty induction motor. The Energy of Wavelet components appear to be useful for detecting different electrical faults. In this paper we will study the problem of broken rotor bars. Voir les détails
Mots clés : Wavelet Packet, Analysis, diagnosis fault, induction motor, broken bar, wavelet paket, analyses
Diagnosis and classification using ANFIS approach ofstator and rotor faults in induction machine
Three-phase squirrel cage induction motors are one of the importantelements of the industrial production system, and are mostly used because oftheir robustness, reliability, relatively simple construction and their low cost.Nevertheless, during their function in different process, this machine types aresubmitted to external and internal stresses which can lead to several electricalor mechanical failures. In this paper, we proposed a reliable approach fordiagnosis and detection of stator short-circuit windings and rotor broken barsfaults in induction motor under varying load condition based on relative energyfor each level of stator current signal using wavelet packet decompositionwhich will be useful as data input of adaptive neuro-fuzzy inference system(ANFIS). The adaptive neuro-fuzzy inference system is able to identify theinduction motor and it is proven to be capable of detecting broken bars andstator short-circuit fault e with high precision. The diagnostic ANFIS algorithmis applicable to a variety of industrial process based on the induction machinefor detection and classified the any faults types. This approach is applied underthe MATLAB software®. Voir les détails
Mots clés : Induction machine, Detection, diagnosis, neuro-fuzzy, Monitoring
Design and Real Time Implementation of Three-PhaseThree Switches Three Levels Vienna Recti?er Based onIntelligent Controllers
This paper treats the control of multilevel rectifier by applying the soft computing technique represented by the fuzzy logic. This latest, provides an inexpensive solution for controlling the ill-known complex systems, while relying on the imitation of human reasoning. In our case, the proposed intelligent controller aims at eliminating the current line harmonics, guaranteing an improved power factor, reducing the output voltage ripple and ensuring the balance between the two voltages across the two capacitors of Vienna rectifier. In order to evaluate the performance of the proposed control for Vienna rectifier, a comparative study in real time via the dSPACE card 1104 has been carried out between the traditional approach based on the conventional controllers and the new method using an intelligent controller. The experimental results confirm that the modified control approach has guaranteed a good quality of source currents in phase with the grid voltages and operation of the studied system with a power factor very close to unity. Furthermore, only one fuzzy controller used has ensured the regulation of the DC bus voltage, the minimization of the undulations for the two partial voltages and the improvement of the error of the voltage balance for the Vienna rectifier. Voir les détails
Mots clés : Vienna rectifier, Fuzzy logic controller, DC bus voltage ripple, Total harmonic distortion, Power factor correction
Predictive Control of Power Electronics Converters in Wind Energy Systems
In order to make a wind power generation truly costeffective and reliable, an advanced control techniques must beused. In this paper, we develop a new control strategy usingModel Predictive Control (MPC) approach for permanentmagnet synchronous generator based wind turbine system. Theproposed control law is based on two points: MPC-based torquecurrentcontrol loop for the generator-side converter to reach themaximum power point of the wind turbine, and MPC-basedcurrent control loop for the grid-side converter to satisfy the gridcode and to help improve system stability. A small-scale windturbine system prototype was built and tested in the laboratory,and the experimental results are provided to verify the validity ofthe developed control methods, MPPT algorithm andperformance of the system operations. Voir les détails
Mots clés : finite-set model predictive control (FSMPC), Permanent Magnet Synchronous Generator (PMSG), Wind Energy Conversion System (WECS), Maximum Power Point Tracking (MPPT) Control, Grid Connected, experimental validation
The Performance of Some Implicit Region-Based ActiveContours in Segmenting and Restoring WeldingRadiographic Images
Several domains are based on image processing and analysis. One of them is the radiographicinspection which is used in Non Destructive Testing (NDT). Active contours, snakes ordeformable models are powerful techniques in image segmentation and restoration. According to theterm related to the input data (image to be treated) those functionals are ranked on two categories:edge-based models and region-based models. Previous studies point out the advantages of the regionbasedmodels over edge-based models. In this paper, we discuss and we summarize the strengths andweaknesses of four implicit region-based active contour models named: Piecewise Constant PC,Piecewise Smooth PS, Local Binary Fitting LBF and Global Local fitting energy GLF. After performingseveral experiments, we have concluded that all the models perform well with homogeneousimages. On the contrary when images are strongly inhomogeneous, the models based on global (PC)or local (LBF) statistic intensity fail to segment such images. The PS model with its great advantage inpreserving the contours has, as a drawback, the high CPU time consuming. The combination of localand global statistic image intensity gives to the GLF model the ability to better deal with such imagesin less CPU time. Voir les détails
Mots clés : segmentation, radiographic images, Level set, region-based active contour, PC, PS, LBF, GLF
Experimental Design of Stand-alone Field Oriented Control for WECS in Variable Speed DFIG-based on Hysteresis Current Controller
This paper presents the experimental design of a stand-alone field-oriented control (FOC) for wind turbine based on a doubly fed induction generator (DFIG). The control law is synthesized using a hybrid FOC-Hysteresis current controller (HCC) in Rotor side converter (RSC) and the stator is connected to the resistive load via rectifier (nonlinear load). The regulation is achieved below the synchronous speed (Hypo-synchronous mode). The implementation is realized using dSPACE1104 single board control and acquisition interface. The obtained results of the proposed control present high performance in steady and transient states. Voir les détails
Mots clés : Doubly fed induction generetor (DFIG), Field oriented control (FOC), Hysteresis current controller (HCC), Rotor/Stator side converter (RSC/SSC), dSPACE1104
Design and Experimental Validation of a Digital Predictive Controller for Variable-Speed Wind Turbine Systems
Advanced control algorithms must be used to make wind power generation truly cost effective and reliable. In this study, we develop a new and simple control scheme that employs model predictive control (MPC), which is used in permanent magnet synchronous generators and grid-connected inverters. The proposed control law is based on two points, namely, MPC-based torque?current control loop is used for the generator-side converter to reach the maximum power point of the wind turbine, and MPC-based direct power control loop is used for the grid-side converter to satisfy the grid code and help improve system stability. Moreover, a simple prediction scheme is developed for the direct-drive wind energy conversion system (WECS) to reduce the computation burden for real-time applications. A small-scale WECS laboratory prototype is built and evaluated to verify the validity of the developed control methods. Acceptable results are obtained from the real-time implementation of the proposed MPC methods for WECS. Voir les détails
Mots clés : Maximum Power Point Tracking (MPPT), Model predictive control (MPC), Permanent Magnet Synchronous Generator (PMSG), Wind Energy Conversion System (WECS)
Real Time Implementation of Grid-connection controlusing Robust PLL for WECS in Variable SpeedDFIG-based on HCC
This paper presents the experimental real timeimplementation of a grid-connection field-oriented control (FOC)for wind turbine based on a doubly fed induction generator(DFIG). A control law is synthesized using a hybrid FOCHysteresisCurrent Controller (HCC) in Rotor side converter(RSC) and the stator is connected to grid via robust PLL (phaselocked loop). The regulation is achieved below the synchronousspeed (Hypo-synchronous mode). The implementation is realizedusing dSPACE1104 single board card control and acquisitioninterface. The obtained results of the proposed control presenthigh performance in steady and transient states with low THD ofthe stator injected current to the grid (<5%). Voir les détails
Mots clés : Doubly fed induction generetor (DFIG), Field oriented control (FOC), Hysteresis current controller (HCC), Rotor side converter (RSC), dSPACE1104
Finite-Set Model Predictive Decoupled Active and Reactive Power Control for Wind Energy Systems
This paper introduces a novel approach for direct power control of three-phase voltage source inverter in grid connected distribution wind energy systems. In this approach, the control of active and reactive power is based on finite-set model predictive control strategy. The proposed strategy has the simplicity of the direct power control technique and doesn’t require any current control loops. To meet the future generation of Permanent magnet synchronous generator wind turbines, a DC-DC boost converter is proposed at the machine-side to simplify the control and potentially reduce the cost of the wind energy system. The wind generation system requirements, such as maximum energy harvesting and regulation of grid active and reactive power are expressed as cost functions. Best switching states are selected and applied to the power converters during each sampling interval based on the minimization of cost functions. The feasibility of the proposed configuration and control scheme are verified through dSPACE 1104 experiments on a low power prototype. Voir les détails
Mots clés : Maximum Power Point Tracking, Finite-set model predictive control, Permanent Magnet Synchronous generator, Wind energy system
Analysis and experimental evaluation of shunt active power filter for power quality improvement based on predictive direct power control
This paper discusses the use of the concept of classical and predictive direct power control for shunt active power filter function. These strategies are used to improve the active power filter performance by compensation of the reactive power and the elimination of the harmonic currents drawn by non-linear loads. A theoretical analysis followed by a simulation using MATLAB/Simulink software for the studied techniques has been established. Moreover, two test benches have been carried out using the dSPACE card 1104 for the classic and predictive DPC control to evaluate the studied methods in real time. Obtained results are presented and compared in this paper to confirm the superiority of the predictive technique. To overcome the pollution problems caused by the consumption of fossil fuels, renewable energies are the alternatives recommended to ensure green energy. In the same context, the tested predictive filter can easily be supplied by a renewable energy source that will give its impact to enhance the power quality. Voir les détails
Mots clés : Harmonic pollution, Power quality, Direct power control, Predictive direct power control, Shunt active filter, Renewable energy source, power factor