In this paper, a novel radiofrequency circuit is designed and developed for an integrated on-chip spiral inductor and inter-digital capacitor of the substrate. Results of extensive simulations ...concerning the influence of both spiral inductor and inter-digital capacitor geometrical parameters on quality factor value are presented. Two scenarios are considered in the simulation; the first operation of buck converter including an ideal capacitor and inductor and then its operation including an inter-digital capacitor and integrated spiral inductor. For both scenarios, we observed that their respective output voltages as well as their respective output currents present the same time responses.
A robust control scheme of a wind turbine system (WTS) based on a dual star induction generator (DSIG) in normal and open-phase fault (OPF) mode is presented in this paper. The strong point of this ...generator that recently attracted the attention of several researchers especially in wind energy field is that it combines the advantages of the squirrel cage induction machine and those of multiphase ones. This research is carried out to reach two main objectives. Firstly, in order to ensure a robust control of the DSIG-based WTS with a low effect of chattering phenomenon, an improved control scheme based on super-twisting continuous sliding mode controllers (STCSMC) is proposed. The second objective is to verify, by an OPF test, the ability of the DSIG to operate in degraded conditions. Finally, simulated results show that more robust control is achieved and that the DSIG-based WTS continues to provide suitable electrical energy to the grid without remarkable effects.
In this paper, we discuss the design and modelling of a spiral inductor with silicon substrate. The equivalent electrical model approved of the integrated spiral inductor acquires into account the ...inductance and quality factor. The performance of the inductance and quality factor values is supported on the mathematical study of the effect geometrical elements on the spiral inductor. The results simulation based on the MATLAB software. Finally, is discussing after simulation about the integrated spiral inductor into a DC-DC converter by PSIM 6.0.
In this paper, we introduce a Coefficient Diagram Method (CDM) to design a conventional PID controller. This controller is used to decrease the frequency fluctuations of a microgrid system composed ...of two renewable energy sources (WTG and STPG) and four controlled elements (UC, FESS, BESS and DEG). The method compares two characteristic polynomials of the same order:, the coefficients of the first polynomial are a function of microgrid parameters and the unknown gains of the PID controller. The second is called the target polynomial; its coefficients are calculated by choosing the stability indices and the equivalent time constant to satisfy the desired performances of the closed-loop system. Mathematically, the order of the polynomial controller determines the type of linear system of equations to solve: undetermined or overdetermined. In our application, the least squares method is used to find an approximate solution to the overdetermined system resulting from this comparison. Digital simulation is performed to test the performance of the microgrid controlled by the CDM-PID controller. The obtained results are compared with two recently published works where the parameters of the PID controllers are tuned by DE and chaotic PSO algorithms. The results show that the CDM-PID controller gives better performance.
This article proposes a control strategy based on a Fractional Order Proportional Derivative (FOPD) controller to enhance the performance and robustness of quadrotors operating in trajectory tracking ...mode. The tuning method proposed for the FOPD controller is based on an ideal Bode transfer function in a closed loop as a fractional reference model. The latter represents the quadrotor desired closed-loop response, and its specification is the key design decision. In this study, we first appropriately set model reference parameters to realistic desired time response characteristics (i.e. overshoot and time constant). Then, the parameters of the FOPD controller are computed using the direct synthesis design approach. The dynamic model of the quadrotor is developed using Lagrange formulation. The model is used to test the performance of the proposed FOPD-based control strategy for the attitude, position, and altitude of the flying robot. The results show that the proposed controller achieved accurately set points tracking with transient responses (i.e. overshoot and time constant) that satisfactorily meet those assigned for their respective reference models. These results validate the effectiveness of our proposed control strategy. Moreover, our comparative studies of the proposed FOPD controller with the conventional PD controller show that the former satisfies better-desired design requirements.
This article presents the application of the harmony search (HS) optimization algorithm for harmonic elimination in a new topology of multilevel inverters with a reduced number of electronic ...switching elements. The main objective of the harmonic elimination strategy is eliminating undesired low rank harmonics in order to improve the quality of the output waveform. The harmonic elimination strategy is achieved by solving a system of nonlinear equations. In this paper, HS optimization is applied using artificial neural networks (ANNs) on a new 21-level inverter topology. The algorithm is based on the music improvisation process. MATLAB programming software was used to develop a HS optimization program for harmonic elimination. The main reason for using selective harmonic elimination based on ANNs in this study is to control the proposed multilevel inverter in real-time. In order to assess the performance of the proposed optimization method, it was compared to particle swarm optimization and the genetic algorithm. A small-scale laboratory of the proposed 21-level inverter is built to validate the simulation results and to prove the efficiency of the proposed control scheme.
This paper explains the implementation of a small-signal model for a new five-level series resonant inverter structure. The proposed circuit combines the advantages of multilevel inverters and the ...characteristics of the physical phenomena, resonance. The small-signal model offers the possibility to design a linearized linear time-invariant (LTI) model around an equilibrium point based on the first-order Taylor series. After that, the performance of the proposed five-level series resonant inverter and its small-signal model are evaluated in MATLAB/Simulink environment. Compared with a MATLAB model generated using the system identification toolbox, the developed small-signal model exhibited a good accuracy in frequency and time domains. In addition, a hardware test bench is developed to validate the proposed model. Both simulation and experimental results show that the proposed multilevel resonant inverter is very interesting for high-voltage high-frequency applications. As a perspective, from the results obtained, we suggest the use of small-signal AC analysis for multilevel series resonant inverter modeling. The paper contains rich information on the recently used tools for dynamic systems modeling and analysis of nonlinear processes that can be applied to modeling and analyzing other power electronics inverters.
This study presents the application of differential evolution algorithm to compute optimal switching angles for a single-phase nine-level inverter to improve the output voltage quality. The topology ...of the proposed inverter in this article is a simple cascade converter composed of two H-bridge cells with non-equal DC voltage sources in order to generate multiple voltage levels. Selective harmonic elimination pulse width modulation strategy is used to improve the generated AC output voltage waveform. The differential evolution optimization algorithm is used to solve non-linear transcendental equations necessary for the (SHPWM). Computational results obtained from computer simulations presented a good agreement with the theoretical predictions. A laboratory prototype based on STM32F407 microcontroller was built in order to validate the simulation results. The experimental results show the effectiveness of the proposed modulation method.
Direct torque control (DTC) of induction motor (IM) is important in many applications. In this paper presents a three-level direct torque control with 24 sectors is applied for IM using PI-flou ...controller and hysteresis regulators based in artificial intelligence techniques. The DTC system is known to offer fast decoupled control between torque and flux via a simple control structure. Nevertheless, DTC system has two major drawbacks, with are the variable inverter switching frequency and high torque output ripple. The validity of the proposed control scheme is verified by simulation tests. The stator flux, torque, and current are determined and compared to the above technique.
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 13-level USAMI is considered and the optimum switching angles are calculated to eliminate the 5th, 7th, 11th, 13th and 17th 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.
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