Browsing by Author "Ouadi, A."

Now showing 1 - 11 of 11

Analysis of finline structures with consideration of metallization thickness and substrate mounting grooves
(Turkish Journal of Electrical Engineering and Computer Sciences, 2007) Ouadi, A.; Bourdoucen, H.
In this paper, mathematical analysis and numerical calculations of main parameters of finline structures with finite metallization thickness and substrate mounting grooves are developed based on the Method of Lines (MoL). The results obtained provide confirmation of the validity of the technique used and prove its simplicity and adequacy for treating different types of planar structures mainly finline based structures. Unilateral and bilateral finlines including practical parameters, such as metallization thickness and grooves ' depths, have been investigated. The effect of these two parameters have been discussed based on realistic configurations and the results show that, at higher frequencies, the grooves supporting the substrate cannot be neglected and, in addition, their influence is more significant than the effect of finite thickness metallic strips. The isolated finline with more complex configuration with a particular interest in applications involving active components was also analyzed. The obtained results confirm the previous published predictions for these types of structures
Analysis of the disturbances in distribution networks using matlab and ATP
(2011) Boutora, S.; Bentarzi, Hamid; Ouadi, A.
The capacitance bank is generally used for compensation in a distributed power grid, if the latter is connected to the utility. An islanded power grid is a distribution grid disconnected from the utility. It can undergo a disturbance namely the ferroresonance phenomenon if the capacitance bank has a non adequate value. In this paper, a study of an islanded power grid is attempted to show the effect of the reconfiguration of the capacitance bank on the ferroresonance. A simulation of the circuit is conducted using Simulink/ MATLAB. In another part of this work, an example of overvoltage study in a distribution medium network using ATP is also presented
Design of an IIR digital filter for phasor measurement improvement based on a hybrid optimization algorithm
(IEEE, 2013) Recioui, Abdelmadjid; Ouadi, A.; Bentarzi, Hamid
Digital differential relay reliability enhancement of power transformer
(2011) Bouderbala, R.; Bentarzi, Hamid; Ouadi, A.
In this paper, an improvement of digital differential relay reliability for protecting a large power transformer is discussed. First, the Fourier sine and cosine coefficients required for fundamental, second, third and fifth harmonics determination have been calculated using rectangular transfer technique. Then, these harmonics have been used in harmonics restrain and blocking techniques used in differential protection system. Simulation testes have been carried out on a variety of magnetizing conditions (normal aperiodic inrush and over excitation conditions) using Simulink/MATLAB. The obtained results shows that the developed approach provides good discrimination between the magnetizing current and the internal fault current
Measurement quality enhancement using digital filter in power grid integrating TCSC
(IEEE, 2015) Abdelkader, Z.; Ouadi, A.; Bentarzi, Hamid
A new approach applied to a digital differential protection of large power transformer
(2010) Bouderbala, R.; Bentarzi, Hamid; Ouadi, A.
A new approach applied to steam turbine controller in thermal power plant
(IEEE, 2012) Bentarzi, Hamid; Chentir, R.A.; Ouadi, A.
A new computer based phasor measurement unit framework
(IEEE, 2009) Ouadi, A.; Bentarzi, Hamid; Maun, J.C.
A Phasor Measurement Unit (PMU) is one of the most important measuring devices that can provide synchronized phasor measurements of voltages and currents in real time from widely spread locations in an electric grid. Indeed this device is crucial to the detection of disturbances and characterization of transient swings. In this work, a new PMU has been designed and implemented including the hardware architecture and the software program using a recent developed algorithm of phasor measurement and frequency estimation. The developed PMU is based on computer associated with an acquisition card AD512 using Matlab as software tool for developing its running program as well as its graphical user interface. Finally, this PMU has been tested in laboratory using network simulator that gives good measurements with an acceptable errors even at offfrequency
A new PMU based power swing detector to prevent mal-operation of distance relay
(Russian electrical engineering, 2016) Ouadi, A.; Bentarzi, Hamid; Chafai, M.
In conventional transmission line protection, a distance relay is used to provide the primary as well as remote backup protection. The voltage and current phasors measurement needed by the distance relay for determining the impedance may be affected by the power disturbances such as power swing. Consequently, this power swing may cause mal-operation of Zone three distance relays which in turn may affect on the reliability of the whole protective scheme. To mitigate these effects and hence improve the relay reliability, this work proposes a new real-time power swing detector using phasor measurement units for blinding the distance relay only during this transient disturbance. However, this developed detector will not block relay when the power swing accompanied with faults. To validate the present work, the performance of developed enhanced distance relay is tested by signals generated by Simulink/MATLAB simulator under different conditions. The test results show that this proposed scheme provides good discrimination between the transient currents and the fault current which in turn it may contribute in enhancing the reliability of Distance relay
Phasor measurement unit reliability enhancement using real-time digital filter
(2011) Ouadi, A.; Bentarzi, Hamid; Maun, J. C.
Phasors and frequency of three-phase power system may be measured with high speed and accuracy using modern power instruments such as Phasor Measurement Unit (PMU). However, this accuracy may be affected by several power disturbances such as fast and slow dc offsets decaying due to sudden current changes, inter- harmonics, etc. To avoid these effects for improving the quality of measurements, this work proposes a new method of real-time filter for removing the unwanted DC offset and hence improving SDFT algorithm. To validate the present method, the performance of developed PMU is tested using the data generated by Simulink/MATLAB simulator. The obtained simulation results are very encouraging
Simulation of data communication in wide area networks employing phasor measurment units
(IEEE, 2013) Recioui, Abdelmadjid; Ouadi, A.; Bentarzi, Hamid