Engineering Commons^™

On The Permittivity Of Xt-Cf20, Aaron Harmon, Wei Zhang, Victor Khilkevich

Electrical and Computer Engineering Faculty Research & Creative Works

In This Work, the Permittivity of a 3D-Printed Carbon Fiber-Loaded Anisotropic Material, XT-CF20, is Examined Further. the Microstructure of XT-CF20 is First Examined Via Optical Imaging and is Shown to Be Composed of Inclusions that Are Aligned with the Print Direction of the Sample. the Permittivity Tensor for the Aligned Microstructure is Then Measured using a Capacitive Measurement Technique and Simulations Are Provided to Demonstrate the Validity of This Measurement Method. the Simulated Permittivity Values for XT-CF20 Samples with Varying Infill Structures Are Then Presented and Compared to the Measured Permittivity Values of Said Samples. an Error of Less Than …

Esd Behavior Of Rf Switches And Importance Of System Efficient Esd Design, Seyed Mostafa Mousavi, Emil Tauber, Amin Pak, David Pommerenke, Daryl G. Beetner, Ketan Shringarpure, Benjamin Lee, Warwick Ka Kui Wong

Electrical and Computer Engineering Faculty Research & Creative Works

RF Switches Are Typically Used in the RF Front-End of Portable Devices Such as Antenna or Matching Tuners to Improve the RF Link Performance. They Are Usually the First Active Devices after the Antenna and Are Vulnerable to Primary or Secondary ESD Discharges to the Antennas. This Paper Investigates the ESD Behavior of One of the High Frequency Switches Used in the RF-Front-End of Portable Devices and Expresses the Importance of the ESD Pulse that Passes through the Switch and Reaches the Next Stage in the RF Path, Possibly Damaging the Next Stage.

Modeling Of A Microstrip Line Referenced To A Meshed Return Plane, Zeyi Sun, Jian Liu, Xiaoyan Xiong, Yuan Liu, Victor Khilkevich, Donghyun Kim, Daryl G. Beetner

Engineering Management and Systems Engineering Faculty Research & Creative Works

Transmission Lines Referenced to Meshed Return Planes Are Widely Used Because of the Physical Flexibility Imparted by the Meshed Plane. Poor Accounting for the Meshed Ground, However, Can Lead to Severe Signal Integrity and Radio Frequency Interference Issues. Full-Wave Simulation Can Characterize the Electrical Performance at an Early Design Stage, But It is Both Time and Computational Resource Consuming. to Make the Simulation More Efficient, a Method is Proposed in This Study to Model Transmission Lines with a Meshed Reference Ground using 2D Analysis. the 2D Analysis is Performed at Several Locations Along the Length of the Trace above the …

Nanosecond Peak Detect And Hold Circuit With Adjustable Dynamic Range, Gabriel Fellner, Lucas Speckbacher, Seyed Mostafa Mousavi, David Johannes Pommerenke, Satyajeet Shinde, Michael Hillstrom, Ram Chundru, Cheung Wei Lam

Electrical and Computer Engineering Faculty Research & Creative Works

This article presents a novel peak detect and hold (PDH) circuit for the measurement of the peak voltage of electromagnetic-field probes. These probes are used to capture the fields generated by electrostatic discharge (ESD) events in nongrounded portable devices. Therefore, a circuit combining small size, low power consumption, and nanosecond operation is needed. A topology using a discrete bipolar transistor structure with operational transconductance amplifier (OTA) and common-base storage capacitor charge control optimally meets the requirements. The circuit performance is demonstrated for different bias point settings. The error between the captured value and the actual pulse peak value is shown …

Improved Quantification Of Defect Cross-Section For Active Microwave Thermography, Logan M. Wilcox, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Active microwave thermography (AMT) is an integrated nondestructive testing and evaluation (NDT&E) technique that features a microwave-based excitation and subsequent thermographic inspection via an infrared camera. AMT has been successfully employed in several industries including aerospace and civil for NDT&E inspections. Since the excitation is microwave-based, an antenna is used to irradiate the sample under test and hence the heating pattern will vary spatially (following the antenna pattern). This nonuniform thermal excitation may limit the ability of AMT to quantify defect cross-sections. Therefore, this work seeks to expand the capabilities of AMT by incorporating a post-processing technique to improve defect …

Structural Transformations In Photo-Thermo-Refractive Glass For Hologram Recording, Roberto Alejandro Alvarez Aguirre

Electronic Theses and Dissertations, 2020-2023

This dissertation focuses on the structural transformations in photo-thermo-refractive (PTR) glass that enable recording phase holograms for efficient transformation of optical beams and high resolution spectroscopy. PTR glass is a multicomponent silicate matrix doped with Ce, Ag, Sn and Sb. It is a holographic phase medium with the ability of permanent refractive index change after UV exposure and thermal development above 500°C due to the precipitation of a NaF crystalline phase. Electronic processes are studied by analyzing the structure of absorption and luminescence bands of PTR glass matrix and its dopants. We analyze the structural transformations in PTR glass from …

Active Photonic Integrated Devices And Circuits On Thin-Film Lithium Niobate Platform, Ehsan Ordouie

Electronic Theses and Dissertations, 2020-2023

This thesis delves into innovative active photonic integrated devices and circuits on the thin-film lithium niobate (TFLN) platform, focusing on their applications and potential future advancements. We introduce a new family of electrooptic modulators (EOMs), the Four-Phase Electrooptic Modulators (FEOMs), which are fabricated using the TFLN platform. These devices effectively mitigate bandwidth and dynamic-range constraints in optical communication systems by reducing dispersion penalties and common-mode noises. Their functionality is demonstrated in a photonic time-stretch system. A dual-polarization variant further exemplifies the mitigation of both dispersion penalties and common-mode noises in long-haul communication links, marking significant strides towards the practical implementation …

Techno-Economic Analysis Of A Utility-Scale Solar Power Plant In Bhutan., Minjur

Cal Poly Humboldt theses and projects

Solar Photovoltaic (PV) technology, which captures energy from the sun, is a rapidly growing technology. Bhutan’s heavy dependence on a single energy source, hydropower, has become a significant concern for energy security. To address this, the Government of Bhutan intends to diversify energy sources using alternative renewable sources.

This research determined that Bhutan has the total potential to develop 3 gigawatts (GW) of solar power based on the utilization of about 7,100 acres of suitable land. The study also identified Tenchhekha, near the capital city of Thimphu, as a potential solar power plant location, with a capacity of 4.85 MWp …

Circulating And Eddy Current Losses In Coreless Axial Flux Pm Machine Stators With Pcb Windings, Yaser Chulaee, Donovin Lewis, Ali Mohammadi, Greg Heins, Dean Patterson, Dan Ionel

Power and Energy Institute of Kentucky Faculty Publications

Printed circuit board (PCB) stators in coreless axial flux permanent magnet (AFPM) machines have been proposed, designed, and studied for use in multiple industries due to their design flexibility and reduction of manufacturing costs, volume, and weight compared to conventional stators. This paper investigates mechanisms and methods of approximating open circuit losses in PCB stators within example wave and spiral winding topologies for a dual rotor, single stator configuration using 3D FEA, analytical hybrid techniques and experiments. The effect of rotor magnet shape, end winding, and active conductor geometry on eddy currents is studied, and some mitigation techniques are proposed. …

Temperature Monitoring In The Refractory Lining Of A Continuous Casting Tundish Using Distributed Optical Fiber Sensors, Muhammad Roman, Hanok Tekle, Dinesh Reddy Alla, Farhan Mumtaz, Jeffrey D. Smith, Laura Bartlett, Ronald J. O'Malley, Rex E. Gerald, Jie Huang

Materials Science and Engineering Faculty Research & Creative Works

This Article Explores the Prospects of using Spatially Distributed Optical Fiber Temperature Sensors based on Rayleigh Optical Frequency Domain Reflectometry (OFDR) Technology in the Continuous Casting of Molten Steel. the Measurement Capability of the Optical Fiber Sensors in a Simulated Steelmaking Environment Was Demonstrated using a Mock Refractory-Lined Tundish, Which Was Fabricated In-House. Single-Mode Optical Fibers, Contained in Protective Stainless-Steel Tubing, Were Embedded in the Refractory Lining of the Mock Tundish. the Instrumented Tundish Was Preheated Up to a Temperature of 960 °C (Recorded at the Surface of the Working Lining) Before the Molten Steel Pour. a Low-Alloy Steel (AISI …

A Study On The Impact Of Silicon And Manganese On Peritectic Behavior In Low Alloy Steels Assisted By Mold Thermal Mapping Technology And Shell Growth Measurements, Damilola Balogun, Muhammad Roman, Rex E. Gerald, Laura Bartlett, Jie Huang, Ronald J. O'Malley

Materials Science and Engineering Faculty Research & Creative Works

Non-Uniform Shell Growth Commonly Caused by the Peritectic Transformation in Low Carbon and Low Alloy Steels Has Been Directly Correlated with Mold Thermal Maps using a Mold Immersion Test into a Molten Steel Alloy. Mold Thermal Maps Were Obtained by Performing Real-Time Temperature Measurements with Optical Fibers Embedded 1 Mm from the Mold Working Surface. Shell Growth Measurements Were Obtained by 3D Optical Scanning of the Recovered Steel Shell Following Immersion Testing. the Effects of Silicon and Manganese on the Shell Growth and Mold Temperature Maps Have Been Examined in Relation to the Peritectic Transformation for Varying Carbon Contents. Results …

การประเมินการปล่อยก๊าซเรือนกระจกตลอดวัฏจักรชีวิตของเครื่องปรับอากาศแบบแยกส่วน และแนวทางการลดปริมาณก๊าซเรือนกระจก : กรณีศึกษาโรงงานผลิตเครื่องปรับอากาศแห่งหนึ่งในประเทศไทย, พิพัฒน์ พงษ์นาค

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้จัดทำขึ้นเพื่อวัตถุประสงค์ในการประเมินการปล่อยก๊าซเรือนกระจกตลอดวัฏจักรชีวิตของผลิตภัณฑ์เครื่องปรับอากาศแบบแยกส่วนชนิดติดผนังขนาดทำความเย็น 3.2 กิโลวัตต์ ซึ่งมีขอบเขตการประเมินตั้งแต่ การได้มาซึ่งวัตถุดิบ การขนส่งวัตถุดิบ กระบวนการผลิต กระจายสินค้า การใช้งาน การกำจัดซาก และแบ่งย่อยขอบเขตการประเมิน เป็น 2 รูปแบบ คือ กรณีใช้งานประเทศไทย และ กรณีใช้งานในทวีปยุโรป เพื่อเสนอมาตรการลดการปล่อยก๊าซเรือนกระจก และคำนวณศักยภาพการลดคาร์บอนฟุตพริ้นท์ของผลิตภัณฑ์ ผลการศึกษาพบว่าปริมาณการปล่อยก๊าซเรือนกระจกตลอดวัฏจักรชีวิตเครื่องปรับอากาศแบบแยกส่วนกรณีใช้งานในประเทศไทย เท่ากับ 13,643 kgCO2eq และผลลัพธ์ปริมาณการปล่อยก๊าซเรือนกระจกกรณีสถานการณ์ใช้งานในทวีปยุโรปเท่ากับ 10,289.63 kgCO2eq ต่อผลิตภัณฑ์ ซึ่งการปล่อยก๊าซเรือนกระจกในแต่ละขั้นตอนของผลิตภัณฑ์ทั้งประเทศไทยและทวีปยุโรปสอดคล้องไปทางเดียวกันคือ ขั้นตอนการใช้งานมีการปล่อยก๊าซเรือนกระจกมากที่สุด และปัจจัยหลักที่ค่าการปล่อยก๊าซเรือนกระจกกรณีใช้งานในทวีปยุโรปน้อยกว่าประเทศไทย เนื่องจากเทคโนโลยีและเชื้อเพลิงในการผลิตไฟฟ้า ซึ่งในทวีปยุโรปมีสัดส่วนการใช้พลังงานสะอาดเป็นสัดส่วนร้อยละ 56 ซึ่งมากกว่าประเทศไทยที่มีสัดส่วนร้อยละ 16 ในส่วนของมาตรการลดการปล่อยก๊าซเรือนกระจกสารนิพนธ์นี้นำเสนอมาตรการลดการปล่อยก๊าซเรือนกระจกที่แบ่งมาตรการเป็นสองด้านได้แก่ ด้านผู้ใช้งานและ ด้านผู้ผลิต โดยมาตรการด้านผู้ใช้งาน ได้แก่ (1) มาตรการการจัดการการใช้พลังงานอย่างมีประสิทธิภาพโดยใช้ Silent mode 4 ชั่วโมง/วัน (2) ใช้ระบบการจัดการพลังงานผ่านซอฟต์แวร์โดยลดใช้พลังงานลง 10 % ต่อปี (3) การไม่ทิ้งสารทำความเย็นสู่ชั้นบรรยากาศ ซึ่งหากดำเนินงานทั้ง 3 มาตรการด้านผู้ใช้งานสามารถลดก๊าซเรือนกระจกกรณีใช้งานในประเทศไทยได้ 3,946 kgCO2eq และกรณีใช้งานในทวีปยุโรป 3,366 kgCO2eq และมาตรการด้านผู้ผลิต ได้แก่ (1) การพัฒนาเครื่องปรับอากาศที่มีประสิทธิภาพการใช้พลังงานสูงขึ้น (2) การศึกษาพัฒนาเครื่องปรับอากาศให้ใช้สารทำความเย็นชนิด R290 (3) การนำสารทำความเย็นจากเครื่องเก่ามาใช้ใหม่โดยวิธีการ reclamation (Batch Distillation) (4) เพิ่มสัดส่วนการใช้ไฟฟ้าจากพลังงานสะอาดในการผลิตเครื่องปรับอากาศ ซึ่งหากดำเนินมาตรการลดก๊าซเรือนกระจกทั้ง 4 มาตรการด้านผู้ใช้ จะสามารถลดการปล่อยก๊าซเรือนกระจกในกรณีใช้งานในประเทศไทยเท่ากับ 2,943 kgCO2eq และกรณีใช้งานในทวีปยุโรปลดลงเท่ากับ 1,193 kgCO2eq

A Study On Peer-To-Peer Energy Trading Market In Low-Voltage Distribution Systems By Considering System Operation Criteria, Pikkanate Angaphiwatchawal

Chulalongkorn University Theses and Dissertations (Chula ETD)

This dissertation investigates the challenges and proposes solutions for enhancing the efficiency and resilience of power systems through peer-to-peer (P2P) energy trading markets, focusing on the context of Thailand. It emphasizes assessing P2P energy transactions to prevent overloading of distribution lines and voltage fluctuations. The study proposes a method to determine the allowable maximum trading power (MTP) for sellers and buyers, considering the operating conditions of the distribution system and forecast error data of photovoltaic (PV) generation and load consumption and leveraging real-time data and algorithms to adjust trading power based on network constraints, ensuring power exchange does not affect …

Design And Development Of Industrial Internet Of Things For Multi-Cloud Factory Vehicle Monitoring System, Patchapong Kulthumrongkul

Chulalongkorn University Theses and Dissertations (Chula ETD)

Material handling equipment, such as forklifts, is broadly used in many industries to increase production efficiency. However, if the equipment unexpectedly breaks down, it can potentially interrupt manufacturing. It's beneficial for the industry to monitor equipment usage data in real-time so that engineers can identify faults before they occur. In this thesis, a prototype for a factory vehicle monitoring system has been designed and implemented. The proposed solution is to acquire real-time usage data from the motor drive of the factory vehicle and send the data to the cloud via narrowband IoT. The received real-time data streams can be stored …

Small Objects Detection In Aerial Imagery For System-On-Chip Fpgas, Wimonthip Saenprasert

Chulalongkorn University Theses and Dissertations (Chula ETD)

Unmanned aerial vehicles (UAVs) offer significant advantages in accessing remote or high-risk locations. Yet, they also present challenges concerning privacy and safety. Effective air traffic management is crucial for ensuring compliance with security regulations. The primary objective is to monitor the flight trajectories of target objects in the airspace, necessitating efficient object detection, especially for distant objects, to facilitate surveillance and preparedness for addressing potential threats. However, the current performance of existing models in detecting small objects is inadequate for real-time surveillance applications. This study advocates prioritizing object detection over precise prediction of object bounding box sizes. We propose a …

Endoscopic Image Super-Resolution Algorithm Using Edge And Disparity Awareness, Mansoor Hayat

Chulalongkorn University Theses and Dissertations (Chula ETD)

Integrating Stereo Imaging technology into endoscopic procedures marks a significant leap forward in medical imaging. This technology equips surgeons with enhanced depth perception and intricate views of internal structures, improving diagnostic accuracy and surgical precision. However, implementing stereo imaging in endoscopy presents certain challenges, such as low- resolution and blurred images that can compromise the quality of medical diagnoses and interventions. To address these issues, our research has developed a cutting-edge endoscopic image super-resolution model. This model incorporates a feature extraction module and a sophisticated cross-view feature interaction module, specifically designed to tackle the complexities of endoscopic images. It was …

Electrode And Electrolyte Design To Develop Advanced Battery Technologies For Large Scale Energy Storage, Wei He

Electronic Theses and Dissertations

Large-scale energy storage devices play a key role in regulating the renewable energy to build a carbon-free sustainable future, but the widely used lithium-ion batteries cannot meet the demands because of the limited lithium resource and high cost. Thus, it is urgent to develop next-generation battery technologies with low cost and high safety. Sodium-ion battery is considered as a promising candidate due to the abundant sodium resources and low cost. Its practical application, however, is hindered by the absence of the advanced electrode materials. The tin-based anodes deliver high theoretical capacities and show great promise for the sodium-ion batteries, but …

Evaluation Of Low-Cost Radiometer For Surface Reflectance Re-Trieval And Orbital Sensor’S Validation, Dinithi Siriwardana Pathiranage

Electronic Theses and Dissertations

This paper evaluates the Arable Mark 2 sensor, an automated and low-cost radiometer, for its potential to retrieve surface reflectance data and validate orbital sensors such as the Landsat-8 (L8) Operational Land Imager (OLI) Level 2 product. While orbital sensors are widely used for monitoring solar radiation changes, managing natural resources, and understanding climatic trends, atmospheric effects can make it challenging to obtain accurate measurements. Equipped with multiple sensors, including long-wave and short-wave radiometers, the Arable Mark 2 sensor can measure upwelling and downwelling irradiance to calculate surface reflectance. To assess the accuracy and consistency of the Arable Mark 2 …

Extended Cross-Referenced Analysis Using Data From The Landsat 8 And 9 Underfly Event, Garrison Gross

Electronic Theses and Dissertations

The Landsat 8 and 9 Underfly Event occurred in November 2021, where Landsat 9 flew beneath Landsat 8 in the final stages before settling in its final orbiting path. An analysis was performed on the images taken during this event, which resulted in a cross-referenced with uncertainties estimated to be less than 0.5%. This level of precision was due in part to the near-identical sensors aboard each instrument as well as the underfly event itself, which allowed the sensors to take nearly the exact same image at nearly the exact same time. This initial calibration was applied before the end …

The Development Of Dark Hyperspectral Absolute Calibration Model Using Extended Pseudo Invariant Calibration Sites At A Global Scale: Dark Epics-Global, Padam Bahadur Karki

Electronic Theses and Dissertations

This research aimed to develop a novel dark hyperspectral absolute calibration (DAHAC) model using stable dark targets of "Global Cluster - 36" (GC-36), one of the clusters from "300 Class Global Classification." The stable dark sites were identified from GC-36 called "Dark EPICS-Global" covering the surface types viz; dark rock, volcanic area, and dark sand. The Dark EPICS-Global shows a temporal variation of 0.02 unit reflectance. This work uses the Landsat-8 (L8) Operational Land Imager (OLI) , Sentinel-2A (S2A) Multispectral Instrument (MSI) , and Earth Observing One (EO-1) Hyperion data for the DAHAC model development, where well-calibrated L8 and S2A …

Exploiting Multimode Antennas For Mimo And Aoa Estimation In Size-Constrained Iot Devices, Abel Zandamela, Alessandro Chiumento Alessandro Chiumento, Alessandro Chiumento, Nicola Marchetti, Max Ammann, Adam Narbudowicz

Articles

This work proposes compact multimode Multiple-Input–Multiple-Output (MIMO) antennas for Angle of Arrival (AoA) estimation in miniaturized Internet of Things (IoT) systems. The method excites different orthogonal radiating modes (TM 21 , TM 02 , and TM 31 modes) for beamforming capabilities, and the AoA performance is investigated using the Multiple Signal Classification (MUSIC) algorithm, executed using numerical and experimental data. The technique is tested at 2.238GHz , while using an antenna diameter

A Label-Free Fiber Ring Laser Biosensor For Ultrahigh Sensitivity Detection Of Salmonella Typhimurium, Shi Qiu, Bin Liu, Yuankui Leng, Edward Fox, Xian Zhou, Binbin Yan, Xinzhu Sang, Long Long, Xingdao He, Jinhui Yuan, Gerald Farrell, Qiang Wu

Articles

The rapid detection of low concentrations of Salmonella Typhimurium (S. Typhimurium) is an essential preventive measure for food safety and prevention of foodborne illness. The study presented in this paper addresses this critical issue by proposing a single mode-tapered seven core-single mode (STSS) fiber ring laser (FRL) biosensor for S. Typhimurium detection. The experimental results show that the specific detection time of S. Typhimurium is less than 20 min and the wavelength shift can achieve -0.906 nm for an S. Typhimurium solution (10 cells/mL). Furthermore, at a lower concentration of 1 cell/mL applied to the biosensor, a result of -0.183 …

Analysis And Design Of Secure Sampled-Data Control Subject To Denial-Of-Service Attacks, Hira Sana, Ghulam Mustafa, Owais Khan, Nouman Ashraf, Abdul Qayyum Khan, Muhammad Abid, Haroom Ur Rashid Khan

Articles

This study addresses the issue of secure control design for cyber-physical systems (CPS) against denial of service (DoS) attacks. We take into account a continuous-time linear system with a convex quadratic performance measure and a sampled linear state feedback control. DoS attacks impose constraints on the CPS, where packets may be jammed between the sensor and controller by a malicious entity, potentially resulting in system instability and performance degradation. We assume that the attacker can perform DoS attacks with a limited time and frequency due to energy restrictions. We devise an efficient procedure using the linear matrix inequality approach to …

Opportunities Of Iot In Fog Computing For High Fault Tolerance And Sustainable Energy Optimization, A. Reyana, Sandeep Kautish, Khalid Abdulaziz Alnowibet, Hossam Zawbaa, Ali Wagdy Mohamed

Articles

Today, the importance of enhanced quality of service and energy optimization has promoted research into sensor applications such as pervasive health monitoring, distributed computing, etc. In general, the resulting sensor data are stored on the cloud server for future processing. For this purpose, recently, the use of fog computing from a real-world perspective has emerged, utilizing end-user nodes and neighboring edge devices to perform computation and communication. This paper aims to develop a quality-of-service-based energy optimization (QoS-EO) scheme for the wireless sensor environments deployed in fog computing. The fog nodes deployed in specific geographical areas cover the sensor activity performed …

A Data-Driven Scheduling Approach For Integrated Electricity-Hydrogen System Based On Improved Ddpg, Yaping Zhao, Jingsi Huang, Endong Xu, Jianxiao Wang, Xiaoyun Xu

Graduate School of Business Publications

The involvement of hydrogen energy systems has been recognised as a promising way to mitigate climate problems. As a kind of efficient multi-energy complementary system, the hydropower-photovoltaic-hydrogen (HPH) system could be an ideal approach to combining hydrogen with an installed renewable energy system to improve the flexibility of energy management and reduce power curtailment. However, the intra-day scheduling of HPH system brings challenges due to the time-related nonlinear hydropower generation process, the complex energy conversion process and the uncertain natural resource supply. Faced with these challenges, an improved deep deterministic policy gradient (DDPG)-based data-driven scheduling algorithm is proposed. In contrast …

Swarm Electrification: A Comprehensive Literature Review, Stephen Sheridan, Keith Sunderland, Jane Courtney

Articles

In the global North, the need to decarbonize power generation is well documented and the challenges faced are endemic to the design of the electrical grids. With networks relying on centralized generation, it can be difficult to replace fossil-fuel power plants with renewable energy sources as generation may be intermittent causing grid instability when there is no ‘spinning reserve’ [1]. In parts of the global south, however, many under-electrified nations have high levels of solar irradiance. This, combined with falling prices for solar panels, is allowing for alternative paths to electrification from costly grid extensions and has resulted in grids …

Adaptive Fuzzy Supplementary Controller For Ssr Damping In A Series-Compensated Dfig-Based Wind Farm, Mohamed Abdeen, Sayed Hosny Ahmed El-Banna, Sara Elgohary, Hend Mostafa, Nora Ghaly, Nourhan Adel, Zeinab Elkhwas, Mohamed Alahmady, Hossam Zawbaa, Salah Kamel

Articles

Although using a series compensation technique in a long transmission line effectively increases the transmittable power; it may cause a sub-synchronous resonance (SSR) phenomenon. Gate-controlled series capacitor (GCSC) is an effective method for SSR damping by controlling the turn-off angle. In the previous studies, a constant supplementary damping controller (SDC) was used for controlling the turn-off angle, which can mitigate the SSR phenomenon. However, these methods can not capture the maximum transmittable power at different operating points. In this paper, a fuzzy logic controller (FLC) is proposed to compute the gain of SDC based on the wind speed and the …

An Adaptive Vector Control Method For Inverter-Based Stand-Alone Microgrids Considering Voltage Reduction And Load Shedding Schemes, Sumit Kumar Jha, Deepak Kumar, Prabhat Ranjan Tripathi, Bhargav Appasani, Hossam Zawbaa, Salah Kamel

Articles

The droop mechanism is widely utilized in a stand-alone microgrid (MG) to regulate power-sharing among distributed generators (DG). However, over the years, the droop phenomena are continually modified to lessen the deviation in voltage and frequency parameters caused due to classical droop. This study suggests computing the droop coefficient for voltage–current (V–I) droop to take into account for proportional power distribution among DGs. In grid utility networks, the conservation voltage reduction (CVR) strategy is widely used to curtail the use of energy. Hence, this paper investigates the CVR's performance for stand-alone MG by performing the adaptive vector control scheme in …

A New Approach To Linear Displacement Measurements Based On Hall Effect Sensors, İsmai̇l Yari̇çi̇, Yavuz Öztürk

Turkish Journal of Electrical Engineering and Computer Sciences

Since displacement is a vital variable to be considered in many industrial applications, displacement sensing devices have been extensively studied both theoretically and experimentally. There have been also many studies on Hall effect-based displacement measurement, but for many systems linearity still remains a problem. This paper discusses different approaches to calculate the magnetic field due to a cylindrical permanent magnet and proposes a new setup geometry with 2-Hall effect sensors and a permanent magnet between them to overcome the linearity problems. Furthermore, theoretical and experimental studies of the discussed displacement sensor were presented by focusing on the linear range and …

Optimizing Constraint Selection In A Design Verification Environment For Efficient Coverage Closure, Vanessa Cooper

CCAC Theses and Dissertations

No abstract provided.