International Journal of Digital Signals and Smart Systems (14 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.
Special Issue on: SSD 2018 Knowledge Processing and Information Quality
Petri Net Based Approach for Scheduling and Rescheduling in Multi-Site Manufacturing System
by MAAOUI AMEL
Abstract: In Multi-Site Manufacturing Systems, operations are subject to a great number of unexpected interruptions that may withdraw the original manufacture schedules. In these cases, rescheduling is prevalent to preserve the performance of the whole system. There are many types of disturbances that can upset the schedule, including; machine failures, processing time delays, clients rush orders, quality problems, transportation failures, etc. In this work, we consider only the machine breakdown as disruption that require schedule updating (rescheduling). For that, we develop a Petri Nets (PN) scheduling and rescheduling approach to model and simulate the Multi-Site Manufacturing System while minimizing the makespan. Finally, we give a case study to analyze the efficiency of the proposed model.
Keywords: Keywords: rescheduling; job shop scheduling; Petri nets; Multi-site Manufacturing systems.
Fusion of Information and Analytics: A Discussion on Potential Methods to Cope with Uncertainty in Complex Environments (Big Data and IoT)
by Eloi Bosse, Basel Solaiman
Abstract: Information overload and complexity are core problems to both military and civilian complex systems, networks and organizations of today. The advances in networking capabilities have created the conditions of complexity by enabling richer, real-time interactions between and among individuals, objects, systems and organizations. On the other hand, what is considered as problems for system designers is technological opportunities for deciders, for instance, the Internet of Things (IoT) and the Big Data. Fusion of Information and Analytics Technologies (FIAT) are key enablers to bring these benefits to deciders. The design of current and future decision support systems (real-time, online, and near real-time) make use of FIAT to support prognosis, diagnosis, and prescriptive tasks for systems. Hundreds of methods and technologies exist, and several books have been dedicated to either analytics or information fusion so far. However, very few have discussed the methodological aspects and the need of an integrating framework or a computational model for an integration of these techniques coming from multiple disciplines. This paper presents a discussion of potential integrating frameworks as well as a description of elements that will support the development of a computational model to evolve FIAT-based systems capable of meeting the challenges of complex environments such as in Big Data and IoT.
Keywords: Information fusion; analytics; decision support; situation analysis; complex systems: Big Data: IoT.
Tracklet and Signature Representation for Multi-Shot Person Re-Identification using Part Appearance Mixture Approach
by Salwa Baabou
Abstract: Recognizing persons in a video surveillance scene in the real world is attractive and is now showing an increasing interest. The task of person Re-Identification(Re-ID) consists in assigning the same identifier to all instances of a particular individual captured in a series of images or videos, even after the occurrence of significant gaps over time or space. The Re-ID system is divided into two main stages:i) extracting feature representations to construct a persons appearance signature and ii)establishing the correspondence/matching by learning similarity metrics or ranking functions. However, appearance-based person Re-ID is a challenging task due to similarity of humans appearance and visual ambiguities across different cameras. This paper provides a representation of the appearance descriptors, called signatures, for multi-shot person Re-ID. First, we will present the tracklets, i.e trajectories of persons. Then, we compute the signature and represent it based on the approach of Part Appearance Mixture (PAM). An evaluation of the quality of this signature representation is also described in order to essentially solve the problems of high variance in a persons appearance, occlusions,illumination changes and persons orientation/pose. To deal with variance in a persons appearance, we represent it as a set of multi-modal feature distributions modeled by Gaussian Mixture Model (GMM). Experiments and results on two public datasets and on our own dataset show good performance.
Keywords: Person Re-Identification (Re-ID); Part Appearance Mixture (PAM); tracklet; signature representation.
A Survey on the Cryptographic approaches for CAN bus Automotive Networks
by Mabrouka Gmiden
Abstract: Electronic Control Units, so called ECUs are a major part in a today cars architecture. These devises are dedicated to control and monitor different functions in vehicle. So security in communication between those ECUs is required in modern cars. A modern cars can contain from 70-100 of ECUs which are interconnected via several protocols to form an overall internal network Controller area network (CAN) bus has become the widely used among these protocols protocol in automotive network since its robustness and efficiency. However, CAN bus does not have enough security prosperities to protect the whole automotive system even to protect its network. Furthermore, todays car is characterized with an important external connectivity through several devices such as of Wi-Fi, Bluetooth, and USB. Unfortunately, the increase of connectivity and complexity of modern in-automotive networks have increased the possibility of hackers against vehicle. So, to leave in-vehicle security level, some defense mechanisms are proposed such as cryptography and intrusion detection. In this paper, we present a survey on current restrictions of CAN bus to insure a secure communication and the different Security Approaches which designed to solve CAN bus security.
Keywords: CAN bus protocol; in-vehicle security; CAN-Bus; vulnerabilities; in-vehicle Network communication; security approaches.
Special Issue on: IC3E'18 Recent Advances in Electrical Systems
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.