International Journal of Digital Signals and Smart Systems (32 papers in press)
Diagnosis of Stator Faults in Permanent Magnet Synchronous Machine Using Finite Element Method
by Manel Fitouri
Abstract: This paper attempts to analyze the characteristics of the inter-turn short circuit fault for the Permanent Magnet Synchronous Motor (PMSM). Based on Finite Element Analysis (FEA), the influence of the stator faults on the behavior of the PM machine is studied. A simple dynamic model for a PM machine with inter-turn winding fault is presented. The precision of the proposed Finite Element (FE) model is verified by a comparison of the simulation results tests. Using the simulated model, a technical method, based on Fast Fourier Transform (FFT) analysis of stator current and electromagnetic torque, is exported to detect the inter turn fault. The technique used and the obtained results show clearly the possibility of extracting signatures to detect and locate faults.
Keywords: Finite element method (FEM); Permanent Magnet Synchronous
Motor (PMSM); winding short-circuit; Fast Fourier Transform (FFT) analysis.
Human Activity Recognition based on Mobile Phone Sensor Data using
Stacking machine learning classifiers
by Mahsa Soufineyestani, Hedieh Sajedi, Vali Tawosi
Abstract: Human activity recognition, which is one of the rapidly growing fields of research, aims to determine which activity is performed by individuals. It has plenty of real-world applications such as health monitoring, abnormal behavior detection, and sports. Therefore, this study focuses on distinguishing and classifying human activities by applying statistical features and using stacking learning methods with the aim of improving the accuracy and precision of the classification. Two main steps are considered at the presented approach. At first, features are extracted from raw sensor data and 26 subsets of the complete feature set are determined and tested to see which subset results in a higher precision classification. Then a feature selection technique based on the Genetic Algorithm is applied to the extracted features to observe if it can improve the results. Comparative results between stacking and single classifiers showed that stacking models have advantages in increasing classification accuracy, especially in the case of those activities that are difficult to distinguish by single classifiers, such as climbing stairs and walking.
Keywords: Human Activity Recognition; Classification; Feature Extraction; Stacking Learning Algorithm.
Home energy management based on Plug-in Electric Vehicle power control in a residential smart grid
by Siwar Khemakhem
Abstract: With the great tendency of Plug in Electric Vehicles (PEVs) development, the integration of this interesting and flexible electric load on the smart grid emerging from energy exchanging between PEV and power grid have drawn a great attention worldwide. In this paper, taking into account smart grid technology, an optimal PEV charge/discharge power management algorithm in residential place is proposed. The purpose of this control strategy is to ensure the energy flow exchanging between PEV and smart home to improve the energy efficiency and to achieve a flattened power load curve. The main contribution of this strategy is to determine the optimal power of the PEV connected at home. The home-to-vehicle operation (H2V) determines the reference power to be absorbed during the off-peak hours and vehicle-to-home operation (V2H) explains the reference power to be injected to home in order to elevate peaks during rush hours. Therefore, this new concept poses important challenges to achieve the smoothness for the power load curve and the stability and the security of smart grid. Simulation results prove the performance of this control approach.
Keywords: PEV; control strategy; vehicle-to-home (V2H); home-to-vehicle (H2V),smoothness.
Using of an Adaptive Fuzzy Speed Controller for Field Oriented Controlled an IPMSM Drives Supplied by a Voltage Source Inverter
by Salma Charmi, Bassem El Badsi, Abderrazak Yangui
Abstract: This paper is aimed to the investigation and performance of the field oriented controlled (FOC) an interior permanent magnet synchronous machine (IPMSM) drives, supplied by a two-level three-phase inverter, using a fuzzy logic toolbox in speed loop system. In recent years, the proposed speed controller has gained more attention for many scientific researchers owing to its several benefits such as more robustness and high precision against reference mechanical speed and/or load torque disturbance effects. Basically, the proposed speed controller consists in adjusting of the proportional and integral gains of the speed controller, in accordance with the speed error and its first time derivative. A simulation-based comparative study between the performance and effectiveness of the developed fuzzy speed controller and the classical one has highlighted the superiority of the adaptive fuzzy control system, in terms of dynamic response, robustness and steady-state error, especially, when there exist motor parameter uncertainties and unexpected load torque changes occur, under forward and reversal motoring.
Keywords: field oriented control strategy; interior permanent magnet synchronous machine; fuzzy logic controller; steady-state error; load torque variations.
Analytical model of multi-coil inductive power transmission system for movable low-power wireless devices with constant speed
by Bilel Kallel, Olfa Kanoun, Hafedh Trabelsi
Abstract: Inductive power transmission IPT can be considered to transfer power to wireless sensors installed in movable devices. The main challenge thereby is the variable mutual inductance and therefore the coupling factor which is decisive for the amount of transmitted energy. Suitable models for the mutual coupling are therefore very important not only for predicting the system behavior, but also for the system design in general. In this paper, we present an analytical model for a multi-coil IPT system consisting of an array of multiple circular air-cored coils connected in series, without any magnetic or soft-magnetic materials around them and a receiving coil in movement in parallel to them and having a constant speed. The equivalent inductance, equivalent mutual inductance, coupling factor and induced voltage and current are estimated. The proposed analytical models are validated by both finite element simulations and experiments. Results fit very well together implying the validity of the proposed model. The model is not only limited to low-power IPT systems having a receiver with constant speed but also it is principally applicable for higher power range applications including electrical vehicles and trains.
Keywords: inductive power transfer; multi-coil system; wireless sensors; movable receiver; analytical model; finite element simulations; experimental verification.
Fault Detection, Isolation and Compensation of Current Measurement Error in Grid connected PV system
by Fatma Ben Youssef
Abstract: Control strategy of grid connected photovoltaic system requires a precise and exact measurement in order to guarantee the desired performance. This work deals with erroneous measurement compensation that can be occurrence in the grid current sensor output, such as: DC offset error and scaled error. Thus, a simple technique for fault measument diagnosis and compensation has been investigated to ensure the system service continuity without good performance. The proposed technique is composed by two steps; the first one consists to isolate and identify the error kind in one of three phase grid current. In the second one, the fault magnitude is computed and injected to the corresponding erroneous measurement signal. In particular, the DC offset and scaled error magnitudes can be determined through analytical analysis of grid current in the synchronous d-axis at grid angular frequency g and 2g, respectively. The suggested algorithm does not need any additional hardware; it can be ensured by implementing two filters. Simulation results are presented to demonstrate the effectiveness of the proposed fault detection, isolation and error compensation method.
Keywords: Grid current; fault detection; error compensation; fault isolation; grid angular frequency; current controller.
Development and Power consumption analysis of Low cost Wireless Sensor Node for Fire Detection
by Shivani Sharma, Chandan , Kailash Chand, Deepak Sharma Sharma, Paramita Guha
Abstract: Fire becomes a problem when it goes untamed and destroys in part or whole the ecological balance of the area. Thus arises a need to develop a system for early detection of fire with significant accuracy. In this work, a wireless sensor network has been developed for fire detection and its essential parameters, such as effective detection distance and power consumption have been monitored. The hardware developed for this system comprises of the components as a controller board and a transceiver. Without the inclusion of energy saving algorithm the system has shown a considerable lifetime and effective detection distance.
Keywords: Wireless Sensor Networks; Fire Detection; Microcontroller; Transceiver; Power consumption.
Special Issue on: SEEMS2018 Signal Processing and Communication
Investigating Customer Satisfaction towards Music Website in Indonesia and India: A Comparative Study
by Reni Diah Kusumawati, Teddy Oswari, Tristyanti Yusnitasari, Himanshu Dutt, Vijay Kumar Shukla
Abstract: The development of information technology has opened the eyes of the world to a new world, new interactions, new market place, and an infinite business network. One proof of the development of these technologies is the Internet, which is causing information technology to make a positive impact on the people. Quite much it has changed the lifestyle of primitive Indonesian and Indian society transforming them into modern societies an evolving parabola. For instance, it has created new types of business opportunities where business transactions are increasingly being made electronically, referred to as click and mortar. There has been an increased awareness about almost everything from traditional product selling through booking orders to downloading commodities like entertainment (read music), for instant consumption. The growing popularity of such websites shows a rise in their demand but what is not clear is satisfaction customers may have with them. This research places an effort to understand the effect of service quality on customer satisfaction on music product websites with respondents from Indonesia and India, and compares are there any differences in consumer attitudes in these countries. It was observed that responsiveness, assurance, and empathy affect on customer satisfaction of music product website and tangibles, reliability and responsiveness have the same impact for both countries, but assurance, empathy and customer satisfaction differ. This is an important milestone in understanding customers intention in buying music online in both countries.
Keywords: Customer satisfaction; service quality; music product; website.
Performance Enhancement of the Triboelectric Energy Harvester by forming Rough Surface Polymer Film Using Poly-Dimethyl-Siloxane (PDMS) +25wt% Water Solution
by Amit Sharma, Poonam Agarwal
Abstract: In this paper, an experimental study of performance enhancement of the triboelectric energy harvester (TEH) by using rough surface Poly-DiMethyl-Siloxane (PDMS) polymer film as one of the tribo layer has been presented. A parallel plate vertical-separation mode type TEH has been fabricated with rough surface morphology PDMS polymer film where rough surface morphology is formed by spin coating diluted PDMS formed of Dow Corning 10:1 PDMS solution +25wt% water on the FR4 PCB board. A cantilever structure as top electrode is implemented utilising 50
Keywords: triboelectric; tribo-pair; energy harvester; PDMS; self-powered;.
A Facial EMG Data Analysis for Emotion Classification based on Spectral Kurtogram and CNN
by Vikram Kehri, Raval Awale
Abstract: In a recent year, the classification of different facial emotion has played a major role in human-computer interface. The facial electromyogram (FEMG) pattern recognition study is a difficult task where classification accuracy is key concerns. The current digital signal processing techniques are not completely effective because of the presence of different noises, added during the acquisition of FEMG signals, and therefore, FEMG data analysis needs strong artificial intelligent techniques along with the advanced signal processing tools. A novel approach for the emotion classification from FEMG signals is proposed in this paper which is based on the kurtogram analysis and convolution neural network (CNN). Kurtogram is time-frequency energy density pattern gives additional information regarding frequency contents. In this work, the kurtogram considered as an input vector introduced to CNN for emotion classification. The different levels of kurtogram are considered to find the best feature set for an efficient result. Facial EMGs for five different facial emotions were recorded using two sensor wireless data acquisition device. In all data from 10 subjects was used for the experimentation. 93% classification accuracy was achieved using our proposed method. The classification results show that the proposed method effectively differentiate the emotion class compares to other methods (SVM, ANN, and KNN).
Keywords: Facial Electromyogram (FEMG); Human Machine Interface (HMI); Convolution Neural Network (CNN); Support Vector Machine (SVM); Artificial Neural Network (ANN); K-Nearest Neighbors (KNN).
Design and Test Music Recommendation System for Online Music Websites Using Collaborative Filtering Approach
by Tristyanti Yusnitasari
Abstract: The music industry is currently growing very rapidly. The limited time possessed by consumers to consume products conventionally is the main reason for online purchases by consumers. This change also occurred in the music industry, so that online music sites that provide convenience in service, and this convenience made consumers decide to buy music products online and abandoned the old habit of consuming conventional music products on CDs. The ease of consuming songs online does not make the user easy to determine the songs they want to hear. The difficulty of users in determining what songs to listen to in a web music can be overcome by the existence of a music recommendation system, where music sites will provide recommendations on songs based on user preferences. This study aims to create a music recommendation system on online music sites to provide convenience for consumers in choosing music products according to their preferences. This study explains the problem of users of online music sites who do not rank a song that has been heard, and overcome it with a recommendation system using user-based collaborative filtering methods.
Keywords: Collaborative Filtering; Music Recommendation System; Music Website; Online System; Rating Prediction.
Identifying the Stabilizing Regions of PI Controller based on Frequency Specifications for a Lab Scale Distillation Column
by JANANI R, Vinayambika. S. Bhat, Thirunavukkarasu Indiran, George V.I
Abstract: The aim of the study is to design and implement decentralized PI controller for a lab scale distillation column based on the frequency specifications. Designing an effective PI controller for an MIMO process is a challenging task because of the loop interaction and system with dead time. In order to eliminate these interaction between the control loops, an ideal decoupling technique is implemented and first order plus dead time model is obtained for each decoupled subsystems. By plotting the boundary locus for each subsystems based on the desired gain and phase margin in (k_p,k_i) plane a wide range of PI values are obtained. Also, the performance measurement calculations were compared and tabulated for various values of k_p and k_i with the boundary locus. In this present research the pressure and temperature near the bottom of the column is considered. It is also shown that the system become unstable when the value of PI controller is selected outside the boundary locus
Keywords: Boundary Locus; Decentralized Controller; Gain Margin; Phase Margin.
Power optimized Hybrid Sorting based Median Filtering
by Nanduri Sambamurthy
Abstract: Nowadays, embedded video and image processing
capabilities are much more demands with image quality. Digital
image noise mostly occurs in a communication channel. The
variety of random variation of white and black dots on the
surface of an image, seriously degrading the image quality.
Median filters are having excellent image denoising
processing capabilities. These filters are particularly reducing
the Salt-and-pepper noise and increase the throughput with less
complexity. In contrast, power efficient remains an untapped
area for improvement in the sorting based network. For this, the
filter is designed with a hybrid sorting network with intelligent
clock gating technique is also presented. The implementation of
the median filter on ARTIX-7(90nm) FPGA. The practical results show
the effectiveness of combined parallel and pipelined with clock
gating architecture reduces the dynamic power and
complexities in terms of FPGA resource usage and frequency.
Keywords: Median filter; Noise reduction; Clock gating; sorting network; FPGA; parallel processing; pipeline technique.
AGE AND GENDER RELATED VARIATIONS IN HUMAN EEG SIGNALS
by Ajantha Pradeep, Ravinda Meegama
Abstract: This research is aimed at analysing EEG data streams from FP1 and F7 channels that reflect activities of the human brain with respect to age and gender. It is mainly focused on finding significant variations in brainwaves detected at frontal parietal lobes of children and adults in both genders. EEG data gathering, data extraction, data cleaning and data filtering technologies were used to observe variations in brainwave patterns among children and adults especially in regions of the brain associated with logical thinking and linguistics. We used cross correlation functionality to obtain similarity between subject data sets in the sample space. Results indicate increased active brain signal patterns near the frontal parietal lobe of young male subjects than in female subjects.
Keywords: EEG; brain waves; brain activity; human behaviour.
A Novel Aggregation Approach to reduce complexity of System
by Sadaf Naqvi, Ibraheem Nasiruddin, Sana Ali
Abstract: This paper presents a novel approach to reduce the complexity of the system. In every field of engineering, the analysis and synthesis of the system is an important step. While analyzing the system, mathematical modeling is the first step. In actual practice the system model is too complicated to analyze, therefore, model order reduction techniques are applied to analyze such a system. In the present work, an exhaustive study is carried out to design reduced order models for a complex system. Conventional techniques are discussed and applied to two area interconnected power system. A method is proposed and applied to multi-area power system. Dynamic responses of original and reduced models have been compared. Results show that the reduced order model is a good representation of the original higher order model.
Keywords: Automatic generation control; frequency domain analysis; Model order reduction; multivariable system; time domain analysis.
A Novel Comparator- A Cryptographic Design in Quantum dot Cellular Automata
by S. Umira R. Qadri, Z.A. Bangi, M. Tariq Banday, G. Mohiuddin Bhat, M. Rafiq Beigh
Abstract: Quantum dot Cellular Automata (QCA), an advanced nanotechnology, is a branch of nano-electronics that attempts to create general computation at nano scale by controlling the position of electrons. The basic logic in QCA does not use voltage level for logic representation; rather it represents the binary state by polarization of electrons in the Quantum Cell, which is basic building block of QCA. QCA technology has large potential to provide high space density, ultra-low power dissipation that enables us to build QCA circuits with faster speed, smaller size & high performance for integration and computation. QCA presents proficient solutions for several arithmetic circuits, such as adders, multipliers, comparators etc. This paper presents a thorough analysis of QCA based Universal FNZ gate  with its stability proof upon which a new design of 1-bit comparator has been proposed. The proposed work uses novel implementation strategies, methodologies and new formulations of basic logic equations to make the proposed designs more efficient in terms of cell count, area, polarization etc. The functionality of universal FNZ Gate based 1-bit comparator has been tested by QCA Designer where a comprehensive comparison with the formerly reported designs confirm the consistent performance and high efficiency of the proposed designs.
Keywords: Nanotechnology; Quantum-dot Cellular Automata; Comparator; Potential Energy.
Photovoltaic Grid-Connected with Transformer less Renewable Source System with Multilevel NPC Inverter
by ANCHAL YADAV, PRATIBHA TIWARI
Abstract: Nowadays, Multilevel NPC inverters have obtained popularity with high power ratings. Photo voltaic solar panels, fuel cells, wind turbines, and similar renewable energy sources can be combined into a multilevel converter system. The strength of the wind, liberal paths of energy in nature, can be tackled by conversion of wind energy system collected of a wind turbine, electrical and electronics system control corresponding system. In research used permanent magnet synchronous generator. Ac grid linked by wind energy with a load. The loads in a grid might be harmful to nature. Hence, the injection of unbalance current into renewable grid should be avoided since these Negative sequence currents and harmonic currents will cause an unwanted improvement of the current line. Dealing with problems is to use effective controllers with multilevel inverters. A multilevel inverter handed down to improve THD. In this case, a nine-level and an eleven-level inverter are used for the set the values of voltage increment and THD decrease with 12.87% to 4.38%. Powers is a limitation of stabilization of DC and the power of reactive is close to unity. Low capacitors filter to eradicate the harmonics present in the system. For the performance evaluation of the approaching for modeling of the AC grid, non-linear load, multilevel inverter and renewable energy resources (e.g., wind power generation) was developed in a MATLAB / SIMULINK environment.
Keywords: Wind Energy; Permanent Magnet Synchronous Motor (PMSM); Total
Harmonic Distortion (THD); Multilevel Inverter.
Simulation of a model DC-DC converter with cascaded via improvement PFC with boost converter and THD using multiple loads
by Anchal Yadav, PRATIBHA TIWARI
Abstract: In this research, we used a converter DC side boost converter yield by forwarding converter for improving the THD and PF. Following the Comparative study made between conventional rectifying bridge diode and Rectifier Bridge with boots converter which is found a better result to maintain system performance. Its concluded the improvement of the THD and PF with the help of the simulation. In this comparative examination improved the quality of the stage and converters by simulation. More investigation of harmonic current and PF was linked by the multiple loads and its non- linearity value of load input current with higher THD.
Keywords: Power factor correction; forward converter; AC/DC converter; DC motor Drive; Boost converter; Total Harmonic Distortion (THD).
Noise Reducing Performance of Anisotropic Diffusion Filter and Circular Median Filter in Digital Images
by NEHA MEHTA, SVAV PRASAD, LEENA ARYA
Abstract: The speckle noise is one of the prominent features found in ultrasound images and it tends to degrade the quality of the image. There is a historic success in the works towards this approach particularly in the medical field related to image de-speckling. In this paper, a scale space non linear anisotropic diffusion process and circular median filter is being combined with un- sharp masking to filter out the speckle noise from the ultrasound images. However, the performance evaluation and the comparison of both the filters are being done at each level of the process by comparing the various parameters of Image Quality Measures. The non linear anisotropic diffusion filter has found to be performing better by two decimal point values in comparison to the circular median filter.rn
Keywords: speckle noise; Ultrasound images; de-speckling; scale –space non linear anisotropic diffusion process; circular median filter; un-sharp masking; Image Quality Measures.rn.
Investigation of Partial Shading Effect on PV Array Configuration
by Vinaya Rana, M.A. Ansari, Yogesh K. Chauhan
Abstract: The shading of any PV panel reduces the overall performance of the panel. To overcome these shading effects, the PV panels are connected in different combinations such as series, parallel, series-parallel and total cross tied configurations. These configurations give a better performance during the partial shading. In this paper, four PV panels of 15 W are analyzed for the experimental study and this work has been validated with the help of simulation in MATLAB/Simulink. The performance of the developed model has been analyzed by the current-voltage and power-voltage characteristics, maximum power, open circuit voltage, short circuit current, overall electrical efficiency, and the fill factor. Among the various configuration methods tested, the total cross tide (TCT) provides maximum power and efficiency as compared to the other configurations with different shading patterns.
Keywords: Renewable energy; Photovoltaic module; PV array configuration; partial shading conditions; PV array characteristics.
Feature Extraction for Brain Tumor Analysis and Classification: A Review
by Rajat Mehrotra, M.A. Ansari
Abstract: The most vital organ of the human body is brain which organizes the whole of the sensory system. The presented paper provides a knowledgeable perception of diverse strategies utilized by various researchers for segmentation and identification of Brain Tumor (BT) using distinct methods and approaches. Among various imaging modalities, MRI images are acknowledged here as an input of superior quality for the purpose of conducting research when compared to other existing modern practices for the superior and more precise outcome. Biomedical image processing has witnessed exponential growth and has been a multidisciplinary area of research attracting experts not only from the medical field but from various other fields of engineering and sciences. Computer-aided diagnostic processing has already become an important part of clinical routine
Keywords: Magnetic Resonance Imaging (MRI); Feature extraction; Classification; Segmentation; Fuzzy C means(FCM); Neuro fuzzy; Genetic Algorithm (GA); Gray-Level Co-Occurrence Matrix (GLCM); Histogram of oriented gradient (HoG); Linear binary pattern (LBP); Discrete wavelet transform (DWT).
Special Issue on: IC3E'18 Recent Advances in Electrical Systems
MRAS speed observer for sensorless adaptive intelligent backstepping controller of induction machines
by Salim ISSAOUNI, Abdesselem Boulkroune, Hachemi Chekireb
Abstract: In this paper, a sensorless adaptive neuro-fuzzy backstepping control scheme is developed for induction machines with unknown model, uncertain load-torque and nonlinear friction where the speed is obtained using the Model Reference Adaptive System (MRAS). Neuro fuzzy systems are used to online approximate the uncertain nonlinearities and an adaptive backstepping technique is employed systematically construct the control law. The MRAS observer is based on two different models, one that is speed independent (reference model) and another that is speed dependent (adjustable model). The speed is estimated via the outputs of the two models. The proposed sensorless controller guarantees the tracking errors converge to a small neighbourhood of the origin and the boundedness of all closed-loop signals what demonstrate the effectiveness of the proposed approach.
Keywords: Induction motors; backstepping control; fuzzy adaptive control; MRAS observer; speed estimation; sensorless control.
Optimal digital PID controller design for regulating blood glucose level of type-I diabetic patients
by Salah Benzian, Aissa Rebai, Aissa Ameur
Abstract: The main objective of this paper is the design and implementation of an optimized PID controller using Xilinx System Generator for the regulation of blood glucose level of type-I diabetic patients. In this work, the Bergman model is used to describe diabetic patient model. The particle swarm optimizationrnalgorithm is used to find the optimal values of the PID controller parameters.rnTo show its effectiveness, the proposed PSO-PID controller is compared to thernclassical PID. Finally, Xilinx System Generator is used to implement the digitalrnoptimal PID controller and verify its capability.
Keywords: Type I diabetic patients; Blood glucose; Bergman\'s model; ParticlernSwarm Optimization; Digital PID controller; Xilinx; System Generator.
Diagnosis Inverter-Fed Induction Motor Fault at Low Load Conditions by Using Demodulation TeagerKaiser Energy Operator based on Stator Current
by Hamid Khelfi, Samir Hamdani, Youcef Chibani
Abstract: This paper presents a reliable indirect technique, which has high robustness for diagnosis broken rotor bars in inverter-fed induction motor at low load condition. This technique based on the analysis in a frequency domain of the temporal signal extracted through TeagerKaiser energy operator demodulation in a steady state of one phase stator current and that without calculating the analytical signal of Hilbert Transform. The theoretical background of the proposed techniques is presented then experimentally validated by using one current signal from testing three different induction machines: a healthy machine, a machine with one broken rotor bar, and with two broken rotor bars. The experiments motors were operated under three load conditions (Low, Medium, and High) and supplied by the inverter at different frequencies. The main obtained results are performed under various operational situations show the robustness and effectiveness of the proposed technique even for the lightly load comparing to these the traditional MCSA method, which this technique can successfully diagnosis the fault inverter-fed induction machine and make it more suitable for the low load condition.
Keywords: induction machine; broken rotor bars; fault diagnosis; demodulation Teager-Kaiser energy operator; spectral analysis.
Intelligent SVM technique of a multi-level inverter for a DFIG-based wind turbine system
by BENBOUHENNI Habib, Zinelaabidine BOUDJEMA, Abdelkader BELAIDI
Abstract: In spite of its several advantages, a traditional direct vector control (DVC) of doubly fed induction generators (DFIGs) driven by variable speed wind turbines has some drawbacks. In this work, a simple and fuzzy space vector modulation (4L-FSVM) is proposed to control the four-level converter in order to reduce total harmonic distortion (THD) of rotor current and powers ripples. The validity of the proposed control technique applied to the DFIG is verified by Matlab/Simulink. The electromagnetic torque, stator reactive power, stator active power and rotor current are determined and compared with the traditional control scheme. Simulation results presented in this article show that the proposed control scheme reduces the THD value, electromagnetic torque ripples and powers ripples compared to conventional control under various operating conditions.
Keywords: Direct vector control; fuzzy space vector modulation; doubly fed induction generator; wind turbine.
PID controller compared with Dynamic Matrix Control applied on disturbed complex system
by Ammar Ramdani, Mohammed Traïche
Abstract: PID controllers are commonly used in many industrial control processes and seemed to be conducive to controlling a wide variety of real processes. They have at the heart of command engineering for many decades, and represent the most common form of feedback. In process control today, the majority of control loops are of the PID type. Its field of application extends in all the sectors. This controller applies and solves the majority of the problems of control. It is thanks to its intuition and its satisfaction of the required performances. However, several complex processes namely: those with a non-minimal phase and / or complex poles, unstable processes, process under constraints or imposed disturbances proceed to a rigorous regulation of the coefficients respecting specified conditions, etc. and the use of advanced process controllers is essential. Dynamic Matrix Control is one of these advanced controllers and can solve this kind of system. It refers to a class of control algorithms in which a process model is used to predict the behavior of the process and optimize its performance. In this paper, we will discuss classic methods of PID types by comparing them with the DMC on a disturbed complex system.
Keywords: Ziegler-Nichols controller; Internal Model Control; Dynamic Matrix Control.
Novel Voltage-based PV MPPT Controller
by Abdelghani Harrag, Yacine Daili
Abstract: This paper focuses on the development of a voltage-based PV MPPT controller. The proposed controller has been used to track the maximum power of PV generator system composed of Solarex MSX-60W PV panel fed by a DC-DC boost converter drived using the proposed voltage-based MPPT powering a resistive load. The proposed MPPT which uses only a voltage sensor has been implemented and validated using Matlab/Simulink environment. Simulation obtained results using the proposed MPPT controller compared to the two sensor IC MPPT prove that the performances of the proposed single sensor MPPT are very close to those of the two sensors IC MPPT regarding dynamic, static and tracking accuracy performances. In addition, the proposed voltage-based MPPT controller can effectively track the maximum power using only one sensor compared to the classical MPPTs using two sensors reducing by the way the cost and the complexity of the PV system.
Keywords: PV; MPPT; Single sensor; DC-DC; Incremental Conductance.
Effects of Temperature on the Electromagnetic Shielding Effectiveness under a plane wave excitation
by Tahar Merizgui, Abdechafik Hadjadj, Mecheri Kious, Bachir Gaoui
Abstract: Sodium Cadmium Orthonavadates (NaCdVO4) is a composite material that presents the advantage for being a light weight material. The general aim behind this paper is to study the shielding behavior of NaCdVO4 in thermal applications and particulary the relationships between the shield parameters: electrical conductivity, magnetic permeability, dielectric constant, temperature and how these parameters effect, the shielding effectiveness (SE) mechanisms of materials against the electromagnetic interference (EMI). The simulation results of the total SE show that the used composite NaCdVO4 has the advantages for being an efficient shielding at high temperature and lightweight. This is mainly due to two keys factors. Firstly, the sample presents a lower absorption mechanism as a result of the increased reflection mechanism of the incident wave. Secondly, DC conductivity of the composite shows that the electrical conduction is a thermally activated mechanism, where the electrical conductivity increases at high temperature in the studied range 583 to 699 K compared to another materials such as copper because its conductivity decrease when the temperature increase. So, the obtained results demonstrate that the electrical conductivity is thermally activated for the NaCdVO4.
Keywords: Shielding effectiveness; DC conductivity; Temperature; Magnetic field; Electric field.
Delay dependent stability analysis of Takagi Sugeno fuzzy time-delays system
by Hadil SOLTANI
Abstract: Generally, nonlinearities and time-delays are inherent characters for the Takagi Sugeno fuzzy system. There has been a lot of research works dealing with this type of systems. Most of these researches are based on measurable states but not all states are available in many physical systems. When such case happens, an observer is designed to estimate the system unavailable states. This work addresses the problem of stability analyses and stabilization for the Takagi Sugeno fuzzy system with time-delays. Motivated by recent concerns in stability issues, a stabilization observer controller for Takagi Sugeno fuzzy time-delay systems is reevaluated in this paper. Based on the fuzzy weighting dependent Lyapunov Krasovskii function approach, we provided, in term of Linear Matrix Inequalities, the sufficient conditions for the existence of a robust state feedback Parallel Distributed Compensation controller that guarantees stability and finding the maximum delay bounds. The effectiveness and the applicability of the designed stabilization controller are illustrated via the truck trailer systems.
Keywords: Takagi Sugeno fuzzy system; Time-delay system; Stability; Linear Matrix Inequalities; Parallel Distributed Compensation.
Direct torque control of induction machine drive based on sliding mode controller and a stator resistance compensator with a new hybrid observer
by Horch Mohamed, Boumediene Abdelmadjid, Baghli Lotfi
Abstract: This paper presents a Direct Torque Control (DTC) based on sliding mode controller approach (SMC) applied to an induction machine drive fed by a power voltage source without speed sensor. The Direct Torque Control is one of the excellent strategies for an induction machine drive. It aims to provide a decoupled control of torque and flux. However, the main problem associated with the conventional DTC was the high torque and flux ripples and variable switching frequency of the devices. It drawback was rectified with the use a control scheme that combined with sliding mode strategy. The sliding mode controller is designed based on flux error and torque error, to make the torque and flux fast and accurate adjustment. The rotor speed estimation is done by an observer using the model reference adaptive system (MRAS) technique whereas the nonlinear sliding mode observer (SMO) is used to get the rotor flux.. The main aim is to achieve a robust and efficient control, which will allow us to test and evaluate the performance of the proposed observer, combined with sensorless control of the induction machine drive. The tests are effectuated and validated by numerical simulations using MATLAB/SIMULINK toolbox. The simulations results show the effectiveness of the proposed sensorless control scheme.
Keywords: nonlinear system; induction machine drive; sliding mode control; direct torque control; sliding mode observer; MRAS observer.
Regrouping of Acoustics Microwaves In Piezoelectric Material (ZnO)
by SVM Classifier
by Hichem Hafdaoui, Djamel Benatia
Abstract: In this paper, we propose a new numerical method for acoustics microwaves detection of an acoustics microwaves signal during the propagation of acoustics microwaves in a piezoelectric substrate Zinc oxide (ZnO) . We have used Support Vector Machines (SVM) ,the originality of this method is the accurate values that provides .this technic help us to identify undetectable waves that we can not identify with the classical methods; in which we classify all the values of the real part and the imaginary part of the coefficient attenuation with the acoustic velocity in order to build a model from which we note the types of microwaves acoustics(bulk waves or surface waves or leaky waves) . By which we obtain accurate values for each of the coefficient attenuation and acoustic velocity. This study will be very interesting in modeling and realization of acoustics microwaves devices (ultrasound ,Radiating structures ,Filter SAW .) based on the propagation of acoustics microwaves
Keywords: Acoustics microwaves; Piezoelectric material ; Support Vector Machines (SVM); Classification.
Pattern Recognition Based Fault Detection of a PM Synchronous Motor under Stator Winding Short Circuit Faults
by Mounir HADEF, Abdesslem DJERDIR, Mohamed Rachid MEKIDECHE, Abdoul Osmane N'DIYAE
Abstract: Abstract: Stator winding short-circuit faults arising from winding insulation faults are among the most frequent faults in Permanent Magnet Synchronous Motors (PMSMs). If left undetected, such fault may be rapidly propagated, resulting in phase-to-phase or phase-to-ground faults, even the breakdown of the whole motor.A powerful fault diagnosis method requires the computation of a fault sensitive quantity and an appropriate method to get a diagnostic index and a threshold which present the edge between faulty and healthy conditions. This is particularly critical for stator short-circuit faults, especially in PMSMs which can cause catastrophic damage to the machine in a very short time. This paper proposes a new detection fault approach based on pattern recognition analysis for detecting the stator inter-turn fault in two phases. Firstly, an image of stator currents in healthy and faulty conditions is composed in the 2-D plane. Then, the extracted parameters according to the obtained image as areas and angles of rectangle shapes are used to detect the stator winding faults. Finally, a fault severity index (FSI) gives a slight or a serious degree of faults in PMSM. The Experimental results are presented in this paper to show the usefulness of the proposed approach.
Keywords: Permanent magnet synchronous motor; inter-turn circuit faults; fault diagnosis; pattern recognition.