Electrical and Computer Engineering Commons^™

Coordination Of Distance And Directional Overcurrent Relays Using A New Algorithm: Grey Wolf Optimizer, Zahra Moravej, Omid Soleimani Ooreh

Turkish Journal of Electrical Engineering and Computer Sciences

Optimal relay coordination has important effects on the stability, security, and reliability of a network. Hence, in this article, a method for optimal coordination of distance (D) and directional overcurrent (DOC) relays is presented. Taking into account the pickup current of the overcurrent relays as an optimization variable, in addition to the time setting multiplier (TSM) and the various characteristics of these relays, optimum and suitable settings for overcurrent and distance relays are obtained. The grey wolf optimizer algorithm has been used as an optimization tool to find optimum settings. The performance of this method has been investigated in 8-bus …

Influence Of Thyristor-Controlled Series Capacitor On Wheeling Cost Incorporating The Impact Of Real And Reactive Power Losses, Kranthi Kiran Irinjila, Jaya Laxmi Askani

Turkish Journal of Electrical Engineering and Computer Sciences

Electric power transmission and transmission pricing are the key issues in the deregulated electric power industry. Factors like fast power demand growth, competition, service outage, and scarce natural resources make transmission systems operate close to their thermal limits. However, new transmission systems cannot be built in due to economic, environmental, and political reasons. For better utilization of existing power system capacities, the power electronic technology-based power system equipment called flexible alternating current transmission system (FACTS) devices like thyristor-controlled series compensators (TCSCs) can be effectively used for operating the transmission grid economically, rapidly, dynamically, and efficiently with increased flexibility and efficiency …

Estimation Of Speed, Armature Temperature, And Resistance In Brushed Dc Machines Using A Cfnn Based On Bfgs Bp, Hacene Mellah, Kamel Eddine Hemsas, Rachid Taleb, Carlo Cecati

Turkish Journal of Electrical Engineering and Computer Sciences

In this paper, a sensorless speed and armature resistance and temperature estimator for brushed (B) DC machines is proposed, based on a cascade-forward neural network and quasi-Newton BFGS backpropagation. Since we wish to avoid the use of a thermal sensor, a thermal model is needed to estimate the temperature of the BDC machine. Previous studies propose either nonintelligent estimators that depend on the model, such as the extended Kalman filter and Luenberger's observer, or estimators that do not estimate the speed, temperature, and resistance simultaneously. The proposed method has been verified both by simulation and by comparison with the simulation …

A Novel Optimization Method For Solving Constrained And Unconstrained Problems: Modified Golden Sine Algorithm, Erkan Tanyildizi

Turkish Journal of Electrical Engineering and Computer Sciences

Recently, the metaheuristic optimization algorithms inspired by nature and different science branches have been powerful solution methods for unconstrained, constrained, and engineering problems. Various metaheuristic optimization algorithms have been proposed and they have been applied to problems in different fields. This paper proposes a novel optimization method based on a modified version of the Golden Sine Algorithm for solving unconstrained, constrained, and engineering problems. The basic idea behind the proposed modified Golden Sine Algorithm (GoldSA-II) depends on finding the optimum solution field in search space by using the decreasing pattern of the sine function and the golden ratio. The performance …

New Optimization Algorithm Inspired By Fluid Mechanics For Combined Economic And Emission Dispatch Problem, Ruyi Dong, Shengsheng Wang

Turkish Journal of Electrical Engineering and Computer Sciences

With the increasing concern over environmental protection, the combined economic emission dispatch (CEED) problem has received much attention. It needs to minimize both fuel cost and emission pollution. This study aims to propose a new metaheuristic algorithm inspired by fluid mechanics to solve the CEED problem with the weighted sum method. The new algorithm simulates the inverse process of fluid flowing spontaneously from high pressure to low pressure, similar to the optimization process of the CEED problem. When applied in two real-world cases, the new algorithm achieves better performance compared with other algorithms in the literature.

Improving The Incremental Conductance Algorithm For Two-Stage Grid-Connectedphotovoltaic Systems, Mehmet Ali̇ Özçeli̇k, Ahmet Serdar Yilmaz

Turkish Journal of Electrical Engineering and Computer Sciences

Efficiency of solar photovoltaic generation plants depends not only on internal operational conditions but also on external atmospheric conditions. Total efficiency is in uenced by various weather conditions such as cloudiness, temperature, and irradiation. In order to generate maximum energy, photovoltaic (PV) arrays should be operated at their maximum power point (MPP), varying external factors like partial shading and surface temperature and amount of radiation coming from the sun. In modern PV systems, maximum power point trackers (MPPTs) have been used in order to reach the MPP, changing with the factors given above. MPPT units are implemented to control DC-DC …

Automated Testing For Distributed Databases With Fuzzy Fragment Reallocation, Akhan Akbulut, Gözde Karataş

Turkish Journal of Electrical Engineering and Computer Sciences

As the Internet and big data become more widespread, relational database management systems (RDBMSs) become increasingly inadequate for web applications. To provide what RDBMSs cannot, during the past 15 years distributed database systems (DDBSs) have thus emerged. However, given the complicated structure of these systems, the methods used to validate the efficiency of databases, all towards ensuring quality and security, have become diversified. In response, this paper demonstrates a system for performing automated testing with DDBSs, given that testing is significant in software verification and that accredited systems are more productive in business environments. The proposed system applies several tests …

A New Method For Detecting Jittered Pri In Histogram-Based Methods, Mostafa Bagheri, Mohammad Hossein Sedaaghi

Turkish Journal of Electrical Engineering and Computer Sciences

Histogram-based methods are among the best methods for deinterleaving, because of their easy implementation. However, they have a basic defect when they encounter a jittered pulse repetition interval (PRI). Jittered PRI is one of the most sophisticated patterns for electronic warfare (EW) receivers. In jittered PRI, the time among successive pulses varies in a totally random manner; thus its detection is very complicated. In this paper we present a new method for extracting jittered PRI from histogram-based methods. Simulation results demonstrate excellent performance of the proposed method in normal as well as hard circumstances where a higher missing pulse rate …

Laser Printer As A Source Of Sensitive Emissions, Ireneusz Kubiak

Turkish Journal of Electrical Engineering and Computer Sciences

Each electronic (electric) device generates electromagnetic emissions during its operation. Most often these emissions are generated unintentionally and they are radiated into the surrounding space in an uncontrolled way. In the case of significant levels of these emissions, they can disturb the operation of other devices or can be used as typical radio emissions. If the nature of their changes corresponds to the processed information occurring in a form of electric signals, the mentioned emissions can be a basis for effective realization of electromagnetic infiltration processes. Most often, these emissions are classified in laboratory conditions using anechoic chambers. Inside such …

Optimization Of Large Electric Power Distribution Using A Parallel Genetic Algorithm With Dandelion Strategy, Jorge Sabattin, Guillermo Fuertes, Miguel Alfaro, Luis Quezada, Manuel Vargas

Turkish Journal of Electrical Engineering and Computer Sciences

The study of electrical distribution of primary networks design is oriented to reduce the construction costs and the energy losses by transmission. The topology for the implementation of distribution networks may vary according to the geographical characteristics of the final users and requires specialized optimization solutions with metaheuristics to improve the energy performance of the electrical power systems. A parallel genetic algorithm (PGA) is proposed to optimize a tree-based topology for large-scale electric power distribution networks. The proposed PGA uses the dandelion code, which allows obtaining tree-feasible solutions within each iteration of the PGA. This cannot be achieved with other …

Fiber-Optic Interferometric Sensor For Monitoring Automobile And Rail Traffic, Jan Nedoma, Marcel Fajkus, Radana Kahankova, Radek Martinek, Marek Dvorsky, Jan Vanus, Vladimir Vasinek, Daniel Cvejn

Turkish Journal of Electrical Engineering and Computer Sciences

This article describes a fiber-optic interferometric sensor and measuring scheme including input-output components for traffic density monitoring. The proposed measuring system is based on the interference in optical fibers. The sensor, based on the Mach-Zehnder interferometer, is constructed to detect vibration and acoustic responses caused by vehicles moving around the sensor. The presented solution is based on the use of single-mode optical fibers (G.652.D and G.653) with wavelength of 1550 nm and laser source with output power of 1 mW. The benefit of this solution lies in electromagnetic interference immunity and simple implementation because the sensor does not need to …

A Matched E-H Plane T-Junction For X-Band Applications, Ashmi Chakraborty Das, Santanu Dwari, Amit Bage

Turkish Journal of Electrical Engineering and Computer Sciences

This paper presents a method of moment-based analysis of an E-H plane T-junction to find its scattering parameters. The results show that the network is not matched at its ports. Therefore, matching networks have been included in the structure to establish matching at the ports. The matching structure includes an inductive window at the H-plane arm and a bisected funnel structure at the junction. Results of the modified structure show simultaneous matching at all the four ports at 9 GHz, which makes it suitable for X-band application.

L-Index Based Contingency Filtering For Voltage Stability Constrained Reactive Power Planning, Farid Karbalaei, Shahriar Abbasi

Turkish Journal of Electrical Engineering and Computer Sciences

One of the most important objectives in reactive power planning (RPP) is maintaining required voltage stability margin under normal and single-contingency situations. For this, an optimization problem must be formulated considering N-1 contingencies constrained for a set of predetermined contingencies. Traditionally, all these contingencies must simultaneously be addressed in the optimization problem. This can dramatically increase the problem dimension and decrease the convergence ability of its solution for large scale applications. This paper uses an L-index based contingency filtering strategy to select a small number of contingencies to be addressed in RPP problem. For this, the predetermined set of all …

Operation Of Three-Level Single-Phase Half-Bridge Npc Inverter-Based Shunt Active Power Filter Under Non-Ideal Grid Voltage Condition With Sliding Mode Controller, Samet Biricik, Hasan Komurcugil, Tuan Ngo, Malabika Basu

Conference papers

In this paper, a new control method is presented for a single-phase three-level neutral point clamped half-bridge shunt active power filter with the aim of eliminating the grid current harmonics. It is shown that the proposed control me thod accurately detects the positive-sequence voltage component under distorted grid condition. With this feature, the performance of the single-phase active power filter under distorted grid voltage condition is improved considerably. Furthermore, the imbalance in the capacitor voltages which occurs in the half-bridge topology is eliminated by adding a feedback term to the current control loop.

Comparison Of Grid Array And Microstrip Patch Array Antennas At 28 Ghz, Zeeshan Ahmed, Patrick Mcevoy, Max Ammann

Conference papers

A millimeter wave Grid Array Antenna for fifth generation (5G) communications is presented. The 20 cell, nearly-rhombic, 40×40 mm2 Grid Array Antenna structure is simulated and fabricated on a Rogers RT/Duroid 5880 substrate with thickness of 0.25 mm. The grid array has |S11|

Interoperable Ocean Observing Using Archetypes: A Use-Case Based Evaluation, Paul Stacey, Damon Berry

Conference papers

This paper presents a use-case based evaluation of the impact of two-level modeling on the automatic federation of ocean observational data. The goal of the work is to increase the interoperability and data quality of aggregated ocean observations to support convenient discovery and consumption by applications. An assessment of the interoperability of served data flows from publicly available ocean observing spatial data infrastructures was performed. Barriers to consumption of existing standards-compliant ocean-observing data streams were examined, including the impact of adherence to agreed data standards. Historical data flows were mapped to a set of archetypes and a backward integration experiment …

Sliding-Mode And Proportional-Resonant Based Control Strategy For Three-Phase Two-Leg T-Type Grid-Connected Inverters With Lcl Filter, Necmi Altin, Saban Ozdemir, Hasan Komurcugil, Ibrahim Sefa, Samet Biricik

Conference papers

In this study, sliding-mode and proportional-resonant based control strategy is proposed for three-phase two-leg T-type grid-connected inverter with LCL filter. The sliding surface function is formed by using the inverter current and capacitor voltage errors. When the inverter current and capacitor voltage feedbacks are included into the control loop, the active damping requirement is automatically resolved. The PR controllers are employed in cascaded manner to generate the references for inverter current and capacitor voltage. The use of PR controllers ensures zero steady-state error in the inverter current, capacitor voltage and grid current. In addition, since the proposed three-phase inverter has …

Generalized Configurations For The Synchronization System Based On Transfer Function Approach, Tuan Ngo, Tuyen Vu, Samet Biricik

Conference papers

This paper presents our research on deriving all the generalized forms for the grid synchronization system of an inverter in the grid-connected applications. The transfer function approach is introduced in order to obtain the generalized second-order and third-order synchronization systems. This approach is based on the orthogonal property of two outputs from the second-order generalized-integrator (SOGI) technique that these two outputs are always 90° difference in phase but only equal in magnitude at the grid frequency. The proposed approach then can provide the generalized forms of any high-order synchronization system, including the second-order and the third-order systems. It is interesting …

Block-Based Classification Method For Computer Screen Image Compression, Kai Wu, Richard Gahan, Patrick O'Friel

Conference papers

In this paper, a high accuracy and reduced processing time block based classification method for computer screen images is presented. This method classifies blocks into five types: smooth, sparse, fuzzy, text and picture blocks. In a computer screen compression application, the choice of block compression algorithm is made based on these block types. The classification method presented has four novel features. The first novel feature is a combination of Discrete Wavelet Transform (DWT) and colour counting classification methods. Both of these methods have only been used for computer image compression in isolation in previous publications but this paper shows that …

Radiation Effects In Tantalum Oxide-Based Resistive Memory Devices, Joshua Stuart Holt

Legacy Theses & Dissertations (2009 - 2024)

There is an increasing need for radiation-hardened electronics as space programs grow in number and scope. Scientific interest in long-term exploration, particularly in high-radiation environments such as Europa, as well as commercial interest in establishing permanent outposts, requires high tolerance of radiation effects. A flash memory device might survive for several years in low Earth orbit, but only a few days in orbit around Europa due to the extremely high levels of radiation encountered there. Meanwhile, commercial interests, including asteroid mining and building a base on the moon or Mars would require electronic systems that could survive for long periods …

Anomaly Inference Based On Heterogeneous Data Sources In An Electrical Distribution System, Yachen Tang

Dissertations, Master's Theses and Master's Reports

Harnessing the heterogeneous data sets would improve system observability. While the current metering infrastructure in distribution network has been utilized for the operational purpose to tackle abnormal events, such as weather-related disturbance, the new normal we face today can be at a greater magnitude. Strengthening the inter-dependencies as well as incorporating new crowd-sourced information can enhance operational aspects such as system reconfigurability under extreme conditions. Such resilience is crucial to the recovery of any catastrophic events. In this dissertation, it is focused on the anomaly of potential foul play within an electrical distribution system, both primary and secondary networks as …

Solid Electrolytes For Better Batteries: A Report On Current Research, Jonathan D. Young

Natural Sciences Student Research Presentations

No abstract provided.

Electro-Magnetic Responsive Ni0.5zn0.5fe2o4 Nano-Particle Composite, Jaiprakash Kanagaraj

Electronic Theses and Dissertations

The purpose of this study is to simulate and synthesize a Radar (or Radiation) Absorbent Material (RAM) by using polymers and nickel zinc ferrite (Ni0.5Zn0.5Fe2O4) magnetic nanoparticles. There is an ardent desire in military, space and electronics for lighter, faster, cheaper and widespread bandwidth providing RAM materials. Electromagnetic property such as magnetic permeability and electric permittivity play a major in controlling the radiation. The appropriate combination of permeability and permittivity properties is acquired for the synthesis of RAM providing wide-ranging bandwidth. The apt property is achieved by rule of mixture, mixing of particular composition of epoxy polymer having low permeability …

Adaptive Interventions Treatment Modelling And Regimen Optimization Using Sequential Multiple Assignment Randomized Trials (Smart) And Q-Learning, Abiral Baniya

Electronic Theses and Dissertations

Nowadays, pharmacological practices are focused on a single best treatment to treat a disease which sounds impractical as the same treatment may not work the same way for every patient. Thus, there is a need of shift towards more patient-centric rather than disease-centric approach, in which personal characteristics of a patient or biomarkers are used to determine the tailored optimal treatment. The “one size fits all” concept is contradicted by research area of personalized medicine. The Sequential Multiple Assignment Randomized Trial (SMART) is a multi-stage trials to inform the development of dynamic treatment regimens (DTR’s). In SMART, a subject is …

Low Power Wide Area Networks (Lpwan): Technology Review And Experimental Study On Mobility Effect, Dhaval Patel

Electronic Theses and Dissertations

In the past decade, we have witnessed explosive growth in the number of low-power embedded and Internet-connected devices, reinforcing the new paradigm, Internet of Things (IoT). IoT devices like smartphones, home security systems, smart electric meters, garage parking indicators, etc., have penetrated deeply into our daily lives. These IoT devices are increasingly attached and operated in mobile objects like unmanned vehicles, trains, airplanes, etc. The low power wide area network (LPWAN), due to its long-range, low-power and low-cost communication capability, is actively considered by academia and industry as the future wireless communication standard for IoT. However, despite the increasing popularity …

Controlled Switching Of Reactive Loads And Commisioning Regimes, Eoin Cowhey

Masters

Switching is a vital task in any power system for ensuring its safe and reliable operation. Switching may be necessary for fault clearance, to ensure wider system stability and to prevent damage to plant. It is essential for isolation, to allow technicians to carry out maintenance tasks safely. Also, switching of reactive loads such as shunt capacitor banks and shunt reactors, is crucial for controlling system voltage.

Switching of some loads however, may produce voltage transients and heavy transient inrush currents which can impact on wider system power quality, impact customers and cause damage or deterioration of the insulation of …

Design And Implementation Of A Micro-Inverter For Photovoltaic Applications, Chi-Thang Phan-Tan

Masters

The objective of this work is to design and build a novel topology of a micro-inverter to directly convert DC power from a photovoltaic module to AC power. In the proposed micro-inverter, a structure with two power stages, which are DC/DC and then DC/AC converters, is used. A novel MPPT algorithm is implemented and evaluated in the DC/DC converter to optimize the solar panel energy production. The new method operates with an efficiency of 97.9%, which is a 1% improvement on the standard method, and a response time of

In this research, the following approach is taken. A literature review …

Improving Time-Of-Flight And Other Depth Images: Super-Resolution And Denoising Using Variational Methods, Salvador Canales Andrade

Open Access Theses & Dissertations

Depth information is a new important source of perception for machines, which allow them to have a better representation of the surroundings. The depth information provides a more precise map of the location of every object and surfaces in a space of interest in comparison with conventional cameras. Time of flight (ToF) cameras provide one of the techniques to acquire depth maps, however they produce low spatial resolution and noisy maps. This research proposes a framework to enhance and up-scale depth maps by using two different regularization terms: Total Generalized Variation (TGV) and Total Generalized Variation with a Structure Tensor …

Interference Analysis And Mitigation Of Telemetry (Tm) And 4g Long-Term Evolution (Lte) Systems In Adjacent Spectrum Bands, Juan Francisco Gonzalez

Open Access Theses & Dissertations

Currently, the telecommunications, radio systems, and many other wireless services in the United States are using the spectrum from the 6 kHz to the 300 GHz frequencies. Although it may seem enough for said systems, as more users and devices are being introduced into the market, the spectrum is limiting the faster introduction of these devices and/or systems. The radio frequency spectrum is home to many transmissions, from amateur radio to cellphone applications, which all share similar frequency bands. By sharing, the number of applications can be increased in a single band, but their performance may be affected. Herein, experiments …

Superpixel-Based Unsupervised Hyperspectral Unmixing, Jiarui Yi

Open Access Theses & Dissertations

Recently, superpixel-based approaches have been proposed for hyperspectral unmixing. The basic assumption of this approach is that the superpixel over-segmentation segments the image into small homogeneous areas. A low-dimensional (LD) image representation is obtained by using the average of the superpixels, which are then used in other image processing tasks up the processing chain. Due to superpixel-segmentation algorithm limitations, the region inside a superpixel may not be homogeneous. Therefore, the average may not be an adequate representation for the superpixel, leading to inaccuracies in the low dimensional representation resulting in errors in the image processing tasks or analysis. Here we …