Javad Sadeh - Academia.edu (original) (raw)

Papers by Javad Sadeh

Electric Power Components and Systems, 2011

Full terms and conditions of use: http://www.informaworld.com/terms-and-conditions-of-access.pdf ... more Full terms and conditions of use: http://www.informaworld.com/terms-and-conditions-of-access.pdf This article may be used for research, teaching and private study purposes. Any substantial or systematic reproduction, redistribution , reselling , loan or sub-licensing, systematic supply or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material.

Context: Intelligent fault locating in transmission lines consists of three main steps: feature e... more Context: Intelligent fault locating in transmission lines consists of three main steps: feature extraction, feature selection, and utilizing a learning tool. Objective: The main objective of this paper is to propose a systematic approach for intelligent fault locating in transmission lines. Method: This paper extracts a group of candidate features by applying a combination of the Wavelet Packet Decomposition (WPD) and Improved Prony Analysis (IPA) methods on single-ended voltage measurements. To have an accurate fault location estimate, useful and efficient features are selected among the candidate features using the regression relief algorithm. In this paper, performances of three regression learning tools including the Generalized Regression Neural Network (GRNN), k-Nearest Neighbor (k-NN) and the Random Forests (RF) in the fault location problem are evaluated and compared, and the best tool is introduced. Results: Numerous training and test patterns are generated through simulation of various fault types in an untransposed transmission line based on different values of fault location, fault resistance, fault inception angle, and magnitude and direction of load current. The results of evaluation using theses patterns show the high efficiency and accuracy of the proposed approach. For various fault types in the test cases, the average values of fault location estimation errors are in the range of 0.153-0.202%. Conclusion: Besides accuracy, the proposed fault locating method is immune against current signal measurement errors and it does not face the problems and costs related to the transmitting and synchronizing data of both line ends.

This paper presents a novel fault location algorithm for series compensated transmission lines, w... more This paper presents a novel fault location algorithm for series compensated transmission lines, which utilizes samples taken in just one terminal from voltage transients generated by fault clearing action of circuit breaker. In this algorithm, using wavelet transform, first and second inceptions of voltage traveling wave to the fault locator are detected and then actual wave speed is determined without any need to the line parameters and precise fault location is calculated. Because of using only one terminal data, algorithm does not need to communication equipments and data synchronization. Due to calculating of wave speed independent of line parameters, accuracy of algorithm is not affected by aging, change of climate and temperature, which modify wave speed. Fault resistance, fault inception angle and fault distance does not affect accuracy of the method. Extent simulations carried out with SimPowerSystem toolbox of MATLAB; confirm capability and high accuracy of the proposed alg...

Journal of Iranian Association of Electrical and Electronics Engineers, 2012

This paper presents an accurate fault location algorithm for compensated transmission line. The d... more This paper presents an accurate fault location algorithm for compensated transmission line. The distributed time domain model is used for modelling of the transmission line. This algorithm does not utilize the compensated device model and does not need any knowledge about the operation mode of the compensated device to compute the voltage drop during the fault period. Samples of voltage and current at both ends of the line are taken synchronously and used to calculate the location of fault. Besides the location of fault, the proposed algorithm estimates the fault resistance accurately. The proposed algorithm is not sensitive to fault resistance and does not require any knowledge of source impedances. The proposed method has been tested using EMTP/ATP model of a 400kV, 300km transmission line, which is compensated by a compensator device. The results of computer simulation confirm the accuracy of the proposed method.

iranian journal of electrical and electronic engineering, 2017

Circuit Breakers (CBs) are critical components in power system for reliability and protection. To... more Circuit Breakers (CBs) are critical components in power system for reliability and protection. To assure their accurate performance, a comprehensive condition assessment is of an imminent importance. Based on dynamic resistance measurement (DRM), this paper discusses a simple yet effective fuzzy approach for evaluating CB’s electrical contacts condition. According to 300 test results obtained from healthy and three defected electrical contacts, the authors describe the special effect of common failures on DRM characteristics and propose seven deterioration indicators. Using these parameters, a fuzzy classifier is suggested to accurately determine contact sets condition. The salient advantage of the proposed model is its capability to recognize the type of contact failure. The feasibility and effectiveness of the proposed scheme has been validated through 40 real life recorded data of some electrical contacts.

Journal of Iranian Association of Electrical and Electronics Engineers, 2016

Journal of Modern Power Systems and Clean Energy, 2020

Islanding refers to a condition where distributed generators (DGs) inject power solely to the loc... more Islanding refers to a condition where distributed generators (DGs) inject power solely to the local load after electrical separation from power grid. Several islanding detection methods (IDMs) categorized into remote, active, and passive groups have been reported to detect this undesirable state. In active techniques, a disturbance is injected into the DG' s controller to drift a local yardstick out of the permissible range. Although this disturbance leads to more effective detections even in well-balanced island, it raises the total harmonic distortion (THD) of the output current under the normal operation conditions. This paper analyzes the power quality aspect of the modified sliding mode controller as a new active IDM for grid-connected photovoltaic system (GCPVS) with a string inverter. Its performance is compared with the voltage positive feedback (VPF) method, a well-known active IDM. This evaluation is carried out for a 1 kWp GCPVS in MATLAB/Simulink platform by measuring the output current harmonics and THD as well as the efficiency under various penetration and disturbance levels. The output results demonstrate that since the proposed disturbance changes the amplitude of the output current, it does not generate harmonics/subharmonics. Thereby, it has a negligible adverse effect on power quality. It is finally concluded that the performance of the sliding mode-based IDM is reliable from the standpoints of islanding detection and power quality. Index Terms-Islanding detection method (IDM), power quality, sliding mode controller, total harmonic distortion (THD), voltage positive feedback (VPF).

Conventional fault location methods using one-terminal voltages and currents are not applicable t... more Conventional fault location methods using one-terminal voltages and currents are not applicable to multi-terminal transmission lines. However, for determination of fault location in three-terminal lines at least voltages and currents of two terminals are necessary. There have been some techniques presented to solve fault location problem for multi-terminal transmission lines. In these methods lumped or distributed frequency domain models are used for transmission lines. In multi-terminal lines, faulty section should be detected before fault location estimation. In this paper, two methods based on time domain transmission line model are presented to identify the faulty section and to determine the location of faults for three terminal transmission lines. In the first method, samples of voltages and currents from all terminals are used while in the second method only the data of two terminals is used for calculating the location of the fault. The proposed algorithms are independent of fault resistance, insensitive to load current and fault inception angle. Furthermore they do not require any knowledge of source impedance and also fault type classification is not necessary. Filtering of dc and high frequency component of waves are not required. The results of computer simulation using EMTP/ATP software confirm the accuracy and precision of the proposed methods.

In this paper a new under frequency load shedding algorithm is introduced and simulated on the IE... more In this paper a new under frequency load shedding algorithm is introduced and simulated on the IEEE 39-Bus test system. Using multiple load estimators and arranging busbar techniques reduces the probability of over or under shedding during the process. Selecting the optimum place for load shedding can have an impact on the frequency at steady state. The main advantages and disadvantages of conventional, new schemes and the proposed algorithm have also been discussed throughout the paper.

In this paper, an approach is proposed for accurate locating of single phase faults in transmissi... more In this paper, an approach is proposed for accurate locating of single phase faults in transmission lines using voltage signals measured at one-end. In this method, harmonic components of the voltage signals are extracted through Discrete Fourier Transform (DFT) and are normalized by a transformation. The proposed fault locator, which is designed based on Random Forests (RF) algorithm, is trained based on these normalized harmonic components. RF algorithm has the capability of learning patterns with a large number of features. The proposed approach only requires voltage signals measured at one-end; hence, there are not problems of transmitting and synchronization of two-end data. In addition, current measurement is not required and the proposed approach is sheltered against current transformer errors and its saturation. No need for very high sampling frequency is another advantage of the proposed approach. Numerous tests carried out on a sample system indicate that accuracy of the p...

with the collaboration of the electrical engineering laboratory of the National Polytechnic Insti... more with the collaboration of the electrical engineering laboratory of the National Polytechnic Institute of Grenoble (INPG), France in 2000. Since then he served as an assistant professor at the Ferdowsi University of Mashhad. His research interests are Power System Protection, Electromagnetic Transients in Power System and Restructuring.

A realistic simulation of fault arc is required in proper design of transmission system equipment... more A realistic simulation of fault arc is required in proper design of transmission system equipment such as fault locators. Usually, in the travelling wave-based fault location algorithms, the effect of the arc of the fault is neglected. The influence of fault arc characteristics on the accuracy of fault locator which is based on the travelling wave theorem, is studied in this paper. Proposed algorithm uses samples taken from two terminals and shows that it is possible to calculate the accurate location of fault by measuring voltage transients caused by the fault. The travelling wave-based algorithm does not use the line parameters. Therefore, the accuracy of algorithm is not affected by aging, change of climate and temperature, which change wave speed. In addition, the effect of fault conditions such as arcing fault resistance, fault inception angle and fault distance are studied on the accuracy of the proposed algorithm. Simulations carried out by SimPowerSystem toolbox of MATLAB software confirm that mentioned parameters do not affect the accuracy of the method.

This paper, presents the effect of a cable line on the maximum overvoltage location along cable l... more This paper, presents the effect of a cable line on the maximum overvoltage location along cable line and reliability indices in the power system with the combined transmission line (overhead line/cable line). Maximum overvoltage has a vital role in insulators design of high voltage cable. On the other hand, recently with the extension of power systems, maintaining the high degree service reliability is very important. High voltage cable insulations have undesirable effect on power system reliability. Therefore, in this study, the effect of cable line length and the number of span before a cable line are investigated on the amount and location of maximum overvoltage. Furthrmore, reliability indices are determined by changing length and age of a cable line in combined transmission line. Results show that cable line length does not change the maximum overvoltage location but has significantly effect on the amount of maximum overvoltage. Also, length and age of cable line effect on power system reliability indices considerably.

In substations, protective equipments such as arresters and neutral transformer are being connect... more In substations, protective equipments such as arresters and neutral transformer are being connected to substation ground grid to protect them against transient overvoltage, firing and other damages. But unfortunately, lack of grounding connection of electrical equipments or high resistance of grounding grid is one of the main reasons which cause risk for staffs and electrical equipments. In this paper, effect of increasing in grounding grid resistance on transient overvoltage which is caused by short circuit, switching and lightning on the interior equipments and safety in a grounding grid at substation is investigated. Effect of transient overvoltage with different short circuits is another subject that is considered. In this paper, indices for ground grid safety are expressed and grounding grid analysis will be done with CYMGrd software. Transient analysis simulations are carried out using DigSilent software and the results of investigation on a real system are presented

Over last two decades, solar and wind energies have become an alternative to traditional energy s... more Over last two decades, solar and wind energies have become an alternative to traditional energy sources. These alternative energy sources are non-polluting, free in their availability and are renewable. Another alternative is tidal energy, which is related to falling and rising ocean water levels. Tidal behavior can be predicted easily and this means that if it is enabling to harness tidal energy, it can be produced power for specific periods of time. In this paper, a new hybrid combination of renewable energy sources is considered. The combination of wind, photovoltaic and tidal is taken into account as a primary and battery as an auxiliary source. The aim of design is to minimize the annualized cost of the generation system over its 20 years of operation. Determining the capacity of hybrid wind, photovoltaic, tidal and battery is formulated as an optimization problem. The objective function is the minimization of the cost with the constrain having specific reliability index. To evaluate the system reliability level, the Equivalent Loss Factor (ELF) has been used as an index. Comparison between hybrid wind, solar and battery and new combination of renewable energy is done and it is shown that the combination of wind, solar, tidal and battery is more economical. Particle Swarm Optimization (PSO) is used for optimal sizing the system. Simulation results are carried out by MATLAB software. It is shown that hybrid system is the best configuration that has minimum cost and can satisfy all constrains.

In this paper, an accurate and efficient method is proposed for fault section estimation and faul... more In this paper, an accurate and efficient method is proposed for fault section estimation and fault distance calculation in distribution systems, based on frequency spectrum components of fault generated traveling waves. Fault occurrence in a radial distribution system generates high frequency traveling waves that can be divided into two parts. Part of them travels between fault location and substation and the other part is reflected between network junctions and substation. By identification of these two parts, the proposed algorithm determines faulted section and exact distance of fault from substation uniquely. Consequently, the main drawback of the impedance based methods which is the multiple-estimation problem is removed. In the proposed method, it is assumed that just one voltage recorder is installed at the distribution substation and additional equipments such as, fault indicators and PQ monitoring devices are also not needed to be installed in the distribution system. The simulations are carried out using ATP software and the results are processed by MATLAB software. Simulation results of various types of faults on a typical distribution system demonstrate high efficiency and accuracy of the proposed method. Effect of different influential parameters such as fault inception angle, fault resistance and load variations has also been taken into account.

In this paper a new single ended fault location method is proposed for underground cable combined... more In this paper a new single ended fault location method is proposed for underground cable combined with overhead lines. In this algorithm fault clearing high frequency transients are used instead of fault-generated transients and the line parameters are not needed. In the proposed algorithm, samples just from voltage transients generated by fault clearing action of circuit breaker are taken from the sending end of the cable line. Applying wavelet transform, the first three inceptions of traveling waves to the fault locator are detected. Using these, the proposed algorithm at first identifies fault section, overhead or cable, and then wave speed is calculated and at last location of fault is determined accurately. Because of using only voltage samples taken from one terminal, it is simple and economic and does not need to GPS and data communication and synchronization. Extensive simulations carried out using SimPow-erSystem toolbox of MATLAB, confirm the capabilities and high accuracy of the proposed method under different system and fault conditions.

2011 International Conference on Advanced Power System Automation and Protection, 2011

The grid-connected power electronic inverters are highly sensitive to grid disturbances and it is... more The grid-connected power electronic inverters are highly sensitive to grid disturbances and it is important to emphasize the necessity to reduce the effects of voltage disturbances on their operation. Among the wide range of power quality disturbances, voltage sags severely affect the performance of voltage source converters (VSC) operation of distributed generation (DG) units. In this paper, small signal model of photovoltaic, DC-DC boost converter and inverter are simulated in Matlab simulink software. The photovoltaic system is connected to a 20kV distribution feeder via a transformer. It can be seen if the voltage sag is happened in the system, the inverter switch current will be increased significantly. In order to protect the power electronic converters' switches during a voltage sag and increase the voltage sag ride through capability, use of fault current limiter (FCL), is proposed. It is shown that if the voltage sag happened with duration of half to thirty cycles, FCL limits the current of power electronic switches. So, the photovoltaic system although is kept connecting with grid during the voltage sag condition, the power electronic switches aren't harmed and have normal current during voltage sag duration.