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The satellite in geostationary orbit present many flexibility due to flexible appendages, solar pressure and fuel sloshing in the tanks which they pose great challenges for accurate attitude control. In this paper, an anti-disturbance proportional-derivative (PD) controller is designed to stabilize the attitude while rejecting the effects of flexible vibrations, environmental disturbances, and unmodeled...
In this paper, an integral sliding mode control is proposed to control a four-leg Distributed Static Compensator (DSTATCOM) system coupled to a superconducting magnetic energy storage (SMES) unit. The proposed SMES based DSTATCOM (SDTATCOM-SMES) is connected to a three-phase four-wire distribution system feeding a set of balanced and unbalanced loads. The control system is designed to compensate the...
The aim of the present paper is to diagnose the mechanical faults in induction motors. We have chosen this part in order to contribute to the diagnosis of electrical machines. The raising of stator current allows detecting the fatigue of the machine failure. The manner of the treatment decides the efficiency of the applied technique. We have examined the static eccentricity fault by a vibration signal...
In this work the idea of graded band gap design in intrinsic-layer is simulated and studied numerically. We study our device model (p-GaN/ i-Ga1−xInxN /n-InN) by using AMPS-1D. The device performance is calculated by transport equations. Effect of series resistance is presented. It has been found that the use of the graded gap in intrinsic region can improve the performance of the GaN/InN solar cell.
This paper presents a new precise vision to diagnose the eccentricity fault using the motor current signature analysis technique (MCSA). The MCSA method was based on analyzing the FFT of the stator current. But, it has many disadvantages, as operating regimes (non-stationary) or his suffering to distingue the characteristic frequencies of several faults such as short circuit, eccentricity, broken...
This research work presents the distribution of the electric field in point-barrier-plane air gaps taking into account the presence of a space charge under electric stress. A new approach of numerical simulation has been applied to study the barrier effect on the electric field distribution using COMSOL Multiphysics®. The introduction of an insulating barrier leads to a reduction of the electric field...
The present paper presents the fault detection of eccentricity using a new qualitative (and quantitative) analysis which based on discrete wavelet transform (DWT) technique. DWT method was based on analyzing the stator current. DWT coefficients of the stator current in a particular frequency band are calculated and analyzed. We used the wavelet mother of Daubechies to analyze the stator current under...
Power Line Communication (PLC) channel is a very challenging environment, this is due to the fact that severe impairments adhering this medium. A more realistic and accurate noise model based symmetric alpha-stable distribution (SαS) is considered in this paper to better fit the properties of real noise inherent in power grid system. In this paper we study the impact of the degree of impulsiveness...
In this paper, we propose a practical study of the microwave characteristics filter based on metamaterials that is characterized by an index of negative refraction. We analyze the reflection and transmission coefficients calculated from transfer matrix simulations on finite lengths of electromagnetic metamaterials, in order to determine the effective refractive index from the effective permittivity...
The High electric field electron transport characteristics in a hexagonal SiC polytype are exposed in this paper. Simulations of the electrons behavior are based on a non-parabolic ensemble Monte Carlo model (EMC). This EMC is implemented to solve the semiclassical Boltzmann equation under high electric field conditions. Also, for more accurate results some effects such as temperature, phonons and...
It is well-known that the wavelet transform is a very useful mathematical tool for scale analysis, with very accurate frequency components estimation for the input signal. In this paper, we propose a new efficient method for QRS detection by employing the Stationary Wavelet Transform (SWT) also known as short wavelet transform. Our approach has been tested over MIT/BIH benchmark database. The obtained...
In this paper, we present an efficient approach to investigate data of EEG-based Brain-Machine Interface (BMI) using a bagging Support Vector Machines (SVMs) for collected data classification from a P3-speller paradigm. The combination of SVMs allows to handle the problem of EEG data variability between the different sessions of the acquisition process. This variability is caused by temporal non-stationarity...
Principal component analysis (PCA) is well-known as a multivariate statistical analysis method, it has been widely and effectively applied for process monitoring. Furthermore, dynamic PCA (DPCA) methods consider serial correlation in addition to cross correlation between variables, and thus reflects the process dynamics. In this paper, we investigate static and dynamic monitoring, where different...
Autonomous electric vehicle path following area has known wide improvement during the last previous years especially with the appearance of new sophisticated control algorithms. The main focus of these control algorithms is to guarantee high performance in term of stability and path tracking with small distance error. In this research, an overview about the most common technics used in autonomous...
This paper presents the experimental real time implementation 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 FOC-Hysteresis Current Controller (HCC) in Rotor side converter (RSC) and the stator is connected to grid via robust PLL (phase locked loop). The regulation is achieved below the...
This paper presents an improved stator active and reactive power control is proposed in wind system (WS) to control doubly fed induction generator (DFIG) in Hyposynchronous mode using maximum power point tracking (MPPT) strategy. A new class of fuzzy logic called an adaptive type-2 fuzzy logic control (T2-FLC) is proposed for wind generation application to control Ird and Irq instead the proportional...
Solar cell/module modeling involves the formulation of the non-linear current versus voltage (I-V) curve. Determination of parameters plays an important role in solar cell/module modeling. This paper presents an application of the improved PSO search method and Particle Swarm Optimization technique for identifying the unknown parameters of solar cell and photovoltaic module models, namely, the series...
The electromagnetic field is an interest scientific subject on overhead transmission lines OTL under high voltage for the reason of their risk on the living organisms such as blood leukemia and others. The aim of this paper is to calculate the electric potential, electric field and the magnetic field around and near of high voltage transmission lines using The ComsolMultyphisics program package based...
Cell nucleus characterization is essential for pathological image analysis. In this article, we propose a shape characterization of the cell nucleus based on some selected shape descriptors. In order to separate automatically the different cell nucleus shapes, we focus our effort on the feature extraction and classification processes. The main contribution of our work is the creation of a new shape...
This paper presents a new design of hybrid Petri net sliding mode control (PNSMC) applied to reach the maximum power point tracking (MPPT) of a variable speed wind energy conversion system. To solve the main and major undesired phenomenon faced by conventional sliding mode control, the high frequency oscillations known as chattering, the design of a hybrid controller based on Petri network sliding...
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