Génie électrique

This paper presents a sensorless direct field oriented control fed interior permanent magnet synchronous motor (IPMSM) by using a known mathematical tool. The Kalman filter is an observer for linear and non-linear systems and is based on the stochastic intromission, in others words, noise. It is a question of studying the state and measurement noises covariances matrices Q and R on the stability of the Extended Kalman Filter. This last is used for the d, q stator current, mechanical speed, rotor position, stator resistance and the load torque estimation. The simulation tests carried out on Matlab Simulink showed that the matrix R improves much more quality of the estimated states while the matrix Q allows the improvement of the estimation process convergence. Key words Permanent magnet synchronous machine, direct filed oriented control, extended Kalman filter, estimation.

Photovoltaic pumping is considered to be the most used application amongst other photovoltaic energy applications in isolated sites. This technology is developing with a slow progression to allow the photovoltaic system to operate at its maximum power. This work introduces the modified algorithm which is a perturb and observe (P&O) type to overcome the limitations of the conventional P&O algorithm and increase its global performance in abrupt weather condition changes. The most significant conventional P&O algorithm restriction is the difficulty faced when choosing the variable step of the reference voltage value, a good compromise between the swift dynamic response and the stability in the steady state. To adjust the step reference voltage according to the location of the operating point of the maximum power point (MPP), a fuzzy logic controller (FLC) block adapted to the P&O algorithm is used. This allows the improvement of the tracking pace and the steady state oscillation elimination. The suggested method was evaluated by simulation using MATLAB/SimPowerSystems blocks and compared to the classical P&O under different irradiation levels. The results obtained show the effectiveness of the technique proposed and its capacity for the practical and efficient tracking of maximum power.

Abstract: This paper presents the modelling and simulation of Static Var Compensator (SVC) in power system studies by MATLAB. In the first step, we have modeled mathematically with MathCAD how to analyze the rating of SVC. In second step, we have conferred modelling ...

Transmission congestion must be managed so that transmission capacity is utilized as efficiently as possible with minimal social welfare loss-usually by system operator. Congestion management must provide incentives for investments in transmission network and generation capacity in the right areas. Minimizing the risks associated with different congestion management methods are important task for every market participant who is trading between different areas. The idea for solving this problem is the use of FACTS devices especially the use of Static Var Compensators (SVC). In this paper the study of SVC with its various modes of operation is investigated. Finally by help of modeling of a power system in MATLAB/PSAT toolbox, and by installing SVC in transmission line, its use as power flow controller and voltage injection is seen. Conclusion is made on different results to see the benefit of SVC in power system.

The purpose of this study is to evaluate the electromagnetic emission of the overhead power line, because these power line generate electromagnetic interaction with other objects near to it. The novelty of this work shows a numerical simulation of the electromagnetic field of the 400 kV line in both permanent and transient states at different positions, based on the finite element method using numerical software. Through the results of this study, it was found that the electromagnetic field in the transient state is very important. The findings of this research can be used to evaluate the field created around transmission lines in order to determine their impact on the environment and human health.

Very few publications have been focused on the mathematical modeling of Flexible Alternating Current Transmission Systems (FACTS) -devices in optimal power flow analysis. A Thyristor Controlled Series Capacitors (TCSC) model has been proposed, and the model has been implemented in a successive QP. The mathematical models for TCSC have been established, and the Optimal Power Flow (OPF) problem with these FACTS-devices is solved by Newtons method. This article employs the Newton- based OPF-TCSC solver of MATLAB Simulator, thus it is essential to understand the development of OPF and the suitability of Newton-based algorithms for solving OPF-TCSC problem. The proposed concept was tested and validated with TCSC in twenty six-bus test system. Result shows that, when TCSC is used to relieve congestion in the system and the investment on TCSC can be recovered, with a new and original idea of integration.

This paper presents a modified harmony search algorithm with dynamically varying bandwidth, named improved dynamic harmony search algorithm (IDHSA) for economic load dispatch (ELD) problems with higher cost functions. The economic load dispatch problem aims to schedule power outputs of the generating units to meet the system load demand at min imu m cost while satisfying the equality and inequality constraints. In the IDHS algorith m, the key difference fro m the conventional HS algorith m is that bandwidth (BW) operator changes dynamically at every iterat ion. The IDHS algorith m is tested with two different cases of power systems without and with transmission losses. The obtained results prove the accuracy and the effectiveness of the IDHS algorithm in determining the best solution compared than other optimization methods recently published in the literature.

The essential objective of optimal power flow is to find a stable operating point which minimizes the cost of the production generators and its losses, and keeps the power system acceptable in terms of limits on the active and reactive powers of the generators. In this paper, we propose the nature-inspired Cuckoo search algorithm (CSA) to solve economic/emission dispatch problems with the incorporation of FACTS devices under the valve-point loading effect (VPE). The proposed method is applied on different test systems cases to minimize the fuel cost and total emissions and to see the influence of the integration of FACTS devices. The obtained results confirm the efficiency and the robustness of the Cuckoo search algorithm compared to other optimization techniques published recently in the literature. In addition, the simulation results show the advantages of the proposed algorithm for optimizing the production fuel cost, total emissions and total losses in all transmission lines.

In this work, an efficient modified harmony search algorithm namely self-adaptive improved harmony search algorithm (SIHS) is proposed to solve economic load dispatch (ELD) problem with considering valve-point loading effects (VPE). The bandwidth parameter within the proposed approach varying dynamically at each new iteration to enhance the accuracy and the convergence velocity of the conventional HSA. To prove the effectiveness and the robustness of the proposed technique, the SIHS is tested on three ELD test systems including VPE: 3-units systems, 13-units system with two different levels of load demand, and 40-units system. Obtained results from SIHS are comparatively measured using 36 comparative algorithms including conventional HS algorithm. The numerical results have proved that the SIHS is more efficient for solving the ED with VPE than many other methods published recently.

Power lines or underground power cables generate electromagnetic interaction with other objects near to them. This study evaluates the magnetic field emitted by underground extra high voltage cables. The presented work aims to show a numerical simulation of the magnetic field of a buried 400 kV underground power line, which is used as a novel prototype in several countries at a short distance. The underground power cable study, in the presence of the current harmonics at different positions, with time variation by finite element resolution, using Comsol Multiphysics with Matlab software in two dimensions. The simulation results illustrate the magnetic flux density variation-in terms of amplitude and distribution as a function of different actual harmonics rates. The underground cable performance and magnetic field have affected by the harmonics effects. The maximum magnetic induction levels generated by significant harmonics are superior to the limits recommended by the international standard norms. In this paper, shielding has been used as an appropriate remedy to attenuate the magnetic field.

In this paper, the dynamic combined economic environmental dispatch problems (DCEED) with variable real transmission losses are tackled using four metaheuristics techniques. Due to the consideration of the valve-point loading effects (VPE), DCEED have become a non-smooth and more complex optimization problem. The seagull optimization algorithm (SOA), crow search algorithm (CSA), tunicate swarm algorithm (TSA), and firefly algorithm (FFA), as both nature and biologic phenomena-based algorithms, are investigated to solve DCEED problems. Our proposed algorithms, SOA, TSA, and FFA, were evaluated and applied on the IEEE five-unit test system, and the effectiveness of the proposed CSA approach was applied on two-unit, five-unit, and ten-unit systems by considering VPE. We defined CSA for different objective functions, such as cost of production, emission, and CEED, by considering VPE. The obtained results reveal the efficiency and robustness of the CSA compared to SOA, TSA, FFA, and to o...

1 University of El-Oued, LEVRES Laboratory, 39000 El-oued Algeria, E-mail: [email protected] 2 University of Biskra, LESM Laboratory, BP.145, Biskra Algeria 3 University of Djelfa, LAADI Laboratory, Djelfa, Algeria 4 University of Nantes, Ecole Polytech Nantes, IREENA-CRTT laboratory, Saint Nazaire, 44600, France SIMULATION AND REAL TIME IMPLEMENTATION OF THREE PHASE FOUR WIRE SHUNT ACTIVE POWER FILTER BASED ON SLIDING MODE CONTROLLER

This paper presents the simulation study of three phase shunt active filter connected to photovoltaic array that based on DPC approach. The proposed system has the ability to inject active power into the grid, however it improves the quality of energy by correcting the power factor and reducing harmonic currents in distribution network. This work interests in improving the control of DC side where it is proposed to use fuzzy logic controller in DC bus voltage regulation loop, this later have been developed to provide better performance compared to conventional PI controller. Otherwise, to extract the maximum power of PV system it is proposed to associate the PV panels by a DC–DC boost converter. Therefore, the control of the boost is based on sliding mode that has good accuracy on following the maximum power point. The results of simulation obviously demonstrate that the designed fuzzy logic controller can be used for improving DC bus voltage under external parameter variation.

This paper focuses on power quality improvement in the distribution network using three phase shunt active power filter, where this later is connected to photovoltaic system. In the present work, a new control method has been presented to eliminate harmonic currents that is caused by nonlinear loads, and to compensate reactive power. This control method has a good accuracy and high efficiency, it bases on direct control of power, rather than conventional one (p-q theory) that relies on current harmonic identification and current control loops. This work proposes to combine a photovoltaic generator with the Dc side of the inverter via boost converter, hence this solution allows to inject the maximum of active power produced by photovoltaic system into the grid in addition to power quality enhancement. The proposed system has been verified by using MATLAB/Simulink and power system. Simulation results demonstrate the effectiveness of the system, where the THD of the source current is r...

Model Predictive Control (MPC) provides various advantages over traditional controllers in power electronics applications. However, reducing the complexity and computational burden of the Finite-control set-model predictive control (FCS-MPC) in multi-leg multilevel inverters is still a challenging task. In this paper, a simplified model predictive direct power control (MPDPC) for a three-level, four-leg grid-connected converter (4L-GCC) is proposed. The main idea of the proposed strategy is to reduce the computational burden of the control algorithm by using only the switching vectors of the first sector to optimize the cost function. The proposed control method can ensure accurate control of active and reactive powers, control of zero-sequence current, as well as DC capacitor voltages balancing without using any weighting factors. Simulation and experimental results are provided to prove the effectiveness and simplicity of the proposed MPC algorithm compared with most-recently proposed solutions. INDEX TERMS Predictive direct power control, simplified model predictive control, four-leg converter, three-level inverter, neutral point clamped converter.

This paper proposes a high performance control scheme for a double function grid-tied double-stage PV system. It is based on model predictive power control with space vector modulation. This strategy uses a discrete model of the system based on the time domain to generate the average voltage vector at each sampling period, with the aim of canceling the errors between the estimated active and reactive power values and their references. Also, it imposes a sinusoidal waveform of the current at the grid side, which allows active power filtering without a harmonic currents identification phase. The latter attempts to reduce the size and cost of the system as well as providing better performance. In addition, it can be implemented in a low-cost control platform due to its simplicity. A double-stage PV system is selected due to its flexibility in control, unlike single-stage strategies. Sliding mode control-based particle swarm optimization (PSO) is used to track the maximum power of the PV system. It offers high accuracy and good robustness. Concerning DC bus voltage of the inverter, the anti-windup PI controller is tuned offline using the particle swarm optimization algorithm to deliver optimal performance in DC bus voltage regulation. The overall system has been designed and validated in an experimental prototype; the obtained results in different phases demonstrate the higher performance and the better efficiency of the proposed system in terms of power quality enhancement and PV power injection.

This paper presents a robust control scheme for shunt active power filter based on predictive direct power control with space vector modulation. The proposed control strategy solves the problem of variable switching frequency of predictive control strategy, and it offers simple and robust hardware implementation. It uses a discrete model of the system based on time domain to generate the average voltage vector, at each sampling period, with the aim of canceling the errors between the estimated active and reactive power values and their references. Concerning the DC-side voltage of the inverter, anti-windup PI controller is tuned offline using particle swarm optimization algorithm to deliver an optimal performance in DC bus voltage regulation. The overall system has been designed, simulated and validated experimentally; the obtained results in different phases demonstrate the higher performance and the better efficiency of the proposed system in terms of power quality enhancement.