Wyniki 1-5 spośród 5 dla zapytania: authorDesc:"Rachid TALEB"

Control of a Uniform Step Asymmetrical Multilevel Inverter using Particle Swarm Optimization

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Harmonic Elimination Strategy (HES) has been a widely researched alternative to traditional PWM techniques. This paper presents the harmonic elimination strategy of a Uniform Step Asymmetrical Multilevel Inverter (USAMI) using Particle Swarm Optimization (PSO) which eliminates specified higher order harmonics while maintaining the required fundamental voltage. This method can be applied to USAMI with any number of levels. As an example, in this paper a seven-level USAMI is considered and the optimum switching angles are calculated to eliminate the fifth and seventh harmonics. The HES-PSO approach is compared to the well-known Sinusoidal Pulse-Width Modulation (SPWM) strategy. Simulation results demonstrate the better performances and technical advantages of the HES-PSO controller in feeding an asynchronous machine. Indeed, the harmonic distortions are efficiently cancelled providing thus an optimized control signal for the asynchronous machine. Moreover, the technique presented here substantially reduces the torque undulations. Streszczenie. W artykule zaprezentowano strategię eliminacji harmonicznych HES w przekształtniku wielopoziomowym asymetrycznym USAMI. Wykorzystano metodę algorytmów rojowych i porównano tę metodę z klasyczną metoda PWM. (Sterowanie wielopoziomowym symetrycznym przekształtnikiem USAMI przy wykorzystaniu algorytmów rojowych) Keywords: Uniform step asymmetrical multilevel inverter (USAMI), Harmonic Elimination Strategy (HES), Particle Swarm Optimization (PSO), Sinusoidal Pulse-Width Modulation (SPWM). Słowa kluczowe: przekształtniki USAMI, sterowanie, eliminacja harmonicznych, algorytm rojowy. 1. Introduction Multilevel inverters have been widely used in last years for high-power applications [1]. Variable-speed drives have reached a wide range of standard applications such as pumps, fans and others. Many of these applications use medium-voltage motors (2300, 3300, 4160 or 6600V), due to their lower current ratings [...]

Simulation Analysis of Geometrical Parameters of Monolithic On-Chip Transformers on Silicon Substrates DOI:10.15199/48.2017.01.62

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In this work, we study the effect of the geometrical parameters of on chip transformer, so to establish a methodology of its dimensioning and consequently its integration in a chip. The inductance and thus the quality factor of the monolithic transformer depend on the geometry of the transformer. Therefore, the geometry of the transformer needs to be optimized to give better quality factor (primary or secondary) and the inductance of the transformer (primary or secondary). The various geometric parameters that influence the performance of the transformer: Our aim is the monolithic or hybrid integration of this type of transformer in power device. Streszczenie. W artykule analizowano wpływ geometrii scalonego transformatora na jego właściwości. Analizowano monolityczny transformator naniesikony na podłoże krzemowe. Analiza parametrów geometrycznych monolitycznego transformatora na podłożu krzemowym Keywords: Monolithic On-chip transformer, Geometrical parameters, Electrical parameters. Słowa kluczowe: tranmsformator monolityczny, geometria transformatora. Introduction If the power supply had only few interests of research in the past, it is today recognized like the major stake to surmount for the next portable electronics generations; power supplies are adapted to various applications via the static converters. The integration of various elements composing a static converter, in particular the passive components, became the main aim today in the field of the power electronics. The monolithic or hybrid integration of semiconductors generated real progress, but the passive components which lend themselves less easily to these techniques, slow down the complete integration of monolithic transformer. It is thus necessary to undertake research on the integration of the passive components. In recent years monolithic transformers have been successfully implemented in RFIC designs. At the time of this writing, monolithic transformers fabr[...]

Modeling and Control of multimachines System Using Fuzzy Logic DOI:10.15199/48.2019.05.34

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AC machines, induction in particular have dominated the field of electric machines. Recently, researchers are interested in machines with a number of phases greater than three. These machines are often called «multiphase machines». This type of machine have large losses and to exploit these, it is possible to connect in series several machines supplied by a single static power converter with each machine in the group have an independent speed control. However, the use of multiphase converters associated with polyphase machines, generates additional degrees of freedom. Thanks to these, several polyphase machines can be connected in series in an appropriate transposition phases [1], [4]. For some applications, series connection of multiphases induction machines can be very interesting. The global system is defined as the domination of a series connected multi-machines mon-converter system (MSCS). This system consists of several machines connected in series in an appropriate transposition of phases. The whole system is supplied by a single converter via the first machine. The control of each machine must be independent of others [5], [7]. In [17], the author uses a classical PI controller to perform a speed control of series connected machines. However, PI controller parameters are highly affected by the system parameters, a temperature rise can cause a degradation of the control quality. Seen from this major drawback, our contribution is to change conventional controllers “PI" with fuzzy logic controllers and test its robustness. Modeling of Multi-machine System The drive system is composed by two induction machines. The first one is a symmetrical six-phase induction motor M(1) which its windings are series connected with that of a second three-phase induction motor M(2). The two motors are supplied by a single power converter which is a six-phase Voltage Source Inverter (VSI). Fig. 1 presents the connect[...]

Integrated Solenoid Inductor with Magnetic Core in a Buck Converter DOI:10.15199/48.2019.08.22

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The recent evolution in radiofrequency (RF) devices and integrated circuit technologies greatly expanded the number of wireless applications [1]. This expansion generated a growing demand for semiconductor manufacturers, requiring a higher integration in RF circuits. However, as passive device performances are directly tied to their geometry (especially for inductors), they end up being the bottleneck on radiofrequency circuitry integration. Inductors are of utmost importance in radiofrequency integrated circuits [2]. These devices are employed in critical building blocks of radiofrequency integrated circuits such as intermediate frequency filters [2], low-noise amplifiers [3], voltage-controlled oscillators [4], and power amplifiers [5]. Current on-chip spiral inductors suffer from large parasitic and area for a meager value of inductance and quality factor [6]. The need to overcome these issues has led to the development inductors with new geometries housing magnetic cores that show an enhanced inductance compared to the air core coil. In this paper, the behavior of solenoid inductors is systematically studied and the impact of the geometrical parameters on its inductance and quality factor. The principal object of my paper is to detail all the phases of design and modeling of a solenoid inductor in order to attain its realization and integrate it into a micro-converter [7]. This structure increases the quality factor value while reducing the constituent dimensions with a small manufacturing cost [8]. Design of solenoid inductor A simple solenoid inductor consists of a metal wire wound around a magnetic core, as shown in figure 1 [9]. Geometric parameters used in the schematic of an integrated solenoid inductor are as follows: the number of turns of the coil N, length of the coil lc, length of the magnetic core (air core) lm, spacing between turns s, width of the magnetic core wm, width of the air core wa, width of coi[...]

Integrated square shape inductor with magnetic core in a buck converter DC-DC DOI:10.15199/48.2019.09.11

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The always-augmenting demand for multifunctional and undersize portable electronic devices is driving the improvement of miniaturized DC-DC converters [1  3]. Such converters are used to shift voltage levels in electronic systems with high efficiency. There are multiple applications for such converters. For example, state-of-the-art portable smart phones and tablet PCs feature multiple components, such as the display panel, MEMS sensors, data storage devices, and cameras, which may require different operating voltage levels. Miniaturizing these converters reduces the overall size of the portable devices [4]. Passive components are the major factor in determining the overall size, cost and performance of portable products. The drive to further miniaturization and integration of portable electronic devices has recently focused on the task of passive functions [5, 6]. Integration of passive devices in the same silicon substrate is desirable in order to reduce this interconnect parasitic, reduce the size and cost of the units and increase the operating frequencies of the radio frequency circuits. Inductors are elementary and important parts in radio frequency integrated circuits [7, 8]. In this paper, the behavior of inductor is systematically studied and the impact of the geometrical parameters on its inductance and quality factor. The principal object of my paper is to detail all the phases of design and modeling of square shape inductor in order to attain its simulation and integrate it into a buck converter. This power inductor with magnetic core increases the quality factor value while reducing the constituent dimensions with a small manufacturing cost. Buck converter DC-DC The buck converter circuit is shown in figure 1. The switch T has a duty cycle D which ranges from 0 to 1. Figure 2 indicates relevant waveforms of the circuit when the switch T is turned ON and OFF at frequency f, with a duty cycle D [9]. T[...]

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