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Full-Text Articles in Power and Energy

Evaluation Of Capacitive Deionization Desalination Technology For Irrigation, Ziad Khalifa, Moustafa Elshafei Prof, Abdalrahman Amer, Eng, Ashraf Seleym Dr, Tamer Samir Eng Feb 2020

Evaluation Of Capacitive Deionization Desalination Technology For Irrigation, Ziad Khalifa, Moustafa Elshafei Prof, Abdalrahman Amer, Eng, Ashraf Seleym Dr, Tamer Samir Eng

Chemical Engineering

Desalination of brackish groundwater has great potential to alleviate the problem of the limited water resources in Egypt. In this paper, we studied the desalination of brackish water for irrigation purposes using capacitive deionization (CDI) technology. We investigated a modular unit for use in greenhouses (GH). A GH for the production of tomato requires about 3.2 m3/d of water. The target CDI unit has a production capacity of 32 m3/d for irrigation of 10 greenhouses from brackish water. The paper provides an extensive simulation study to illustrate the influence of various design parameters and to unveil the CDI technology pros …


Short-Term Electricity Price Forecasting In Deregulated Electricity Market Based On Enhanced Artificial Intelligence Techniques, Pourdaryaei Alireza Feb 2020

Short-Term Electricity Price Forecasting In Deregulated Electricity Market Based On Enhanced Artificial Intelligence Techniques, Pourdaryaei Alireza

Student Works (2020-2029)

Electricity price forecasting is considered as one of prime factors for operation, planning and scheduling of price-setter market participants. However, possessing time variant, non-linear and non-stationary behaviors make the electricity price a complex signal. The main challenge in this area is providing highly accurate and efficient day-ahead price forecasting. A suitable feature selection technique, which is able to model the interacting features and nonlinearities of the forecast processes, is still required although researches have been performed for day-ahead forecasting. In this research, a hybrid electricity price forecasting methodology is proposed using two-stage feature selection method and optimization using adaptive neuro-fuzzy …


Residential Thermal Storage And Cooling, Joao Marcelo Rocha Belmonte, Jacob Anderson, Andrew Clarke, Daphne Forester, Bianca Hardtke, Josh Hartman, Marc D. Compere Jan 2020

Residential Thermal Storage And Cooling, Joao Marcelo Rocha Belmonte, Jacob Anderson, Andrew Clarke, Daphne Forester, Bianca Hardtke, Josh Hartman, Marc D. Compere

Sustainability Conference

No abstract provided.


Dual-Axis Solar Tracker, Bryan Kennedy Jan 2020

Dual-Axis Solar Tracker, Bryan Kennedy

All Undergraduate Projects

Renewable energies, and fuels that are not fossil fuel-based, are one of the prolific topics of debate in modern society. With climate change now becoming a primary focus for scientists and innovators of today, one of the areas for the largest amount of potential and growth is that of the capturing and utilization of Solar Energy. This method involves using a mechanical system to track the progression of the sun as it traverses the sky throughout the day. A dual-axis solar tracker such as the one designed and built for this project, can follow the sun both azimuthally and in …


Computational Assessment Of Aortic Valve Function And Mechanics Under Hypertension, Saurav Kadel Jan 2020

Computational Assessment Of Aortic Valve Function And Mechanics Under Hypertension, Saurav Kadel

Browse all Theses and Dissertations

Calcific aortic valve disease (CAVD), the most common valvular heart disorder, is associated with complications such as stroke, heart attack, aortic aneurysm, left ventricular hypertrophy, and ultimately death. While hypertension has been identified as a major risk factor for CAVD, the mechanisms by which it may promote calcification are still unknown. Given the sensitivity of valvular tissue to mechanical stress alterations, the hemodynamic abnormalities linked to hypertension may play a role in the development of CAVD. Further, the effects of hypertension on the left ventricular functionality and coronary flow resistance remain largely uninvestigated. Hence, the objectives of this thesis were …


Microgrid-Enabled Reactive Power Support To Enhance Grid Economics, Sarhan Hasan Jan 2020

Microgrid-Enabled Reactive Power Support To Enhance Grid Economics, Sarhan Hasan

Electronic Theses and Dissertations

Reactive power plays an essential role in voltage control and stability in electric power systems. Various Volt/VAR techniques are utilized in electric power systems to maintain the voltage profile within defined acceptable limits and accordingly provide reliability and stability. Reactive power has been commonly generated through large-scale synchronous generators or distributed capacitor banks to provide proper transmission and distribution level system management, however, reactive power can be further used as an effective means to reduce total system operation cost. In this dissertation, an optimal reactive power model is proposed to determine the optimal nodal reactive powers that result in the …


Deep Reinforcement Learning For The Optimization Of Building Energy Control And Management, Jun Hao Jan 2020

Deep Reinforcement Learning For The Optimization Of Building Energy Control And Management, Jun Hao

Electronic Theses and Dissertations

Most of the current game-theoretic demand-side management methods focus primarily on the scheduling of home appliances, and the related numerical experiments are analyzed under various scenarios to achieve the corresponding Nash-equilibrium (NE) and optimal results. However, not much work is conducted for academic or commercial buildings. The methods for optimizing academic-buildings are distinct from the optimal methods for home appliances. In my study, we address a novel methodology to control the operation of heating, ventilation, and air conditioning system (HVAC).

We assume that each building in our campus is equipped with smart meter and communication system which is envisioned in …


Experimental Investigation Of Low-Voltage Silicon Carbide (Sic) Semiconductor Devices For Power Conversion Applications, Saleh Salem H. Alharbi Jan 2020

Experimental Investigation Of Low-Voltage Silicon Carbide (Sic) Semiconductor Devices For Power Conversion Applications, Saleh Salem H. Alharbi

Electronic Theses and Dissertations

Enhancing the performance and efficiency of power converter systems requires fast-switching power devices with considerably low switching and conduction losses. Silicon (Si) semiconductor devices are the essential components in electronic converter designs, and their behaviors and switching characteristics determine the system’s overall performance and efficiency. These conventional Si devices are nearing to hit their physical and operational limits in meeting power converter requirements with respect to high temperature and large voltage conditions. However, silicon carbide (SiC) power devices enable greater converter efficiency and better power density, particularly under hard switching frequencies and high output voltages due to their outstanding material …


Real-Time Detection Of Demand Manipulation Attacks On A Power Grid, Srinidhi Madabhushi Jan 2020

Real-Time Detection Of Demand Manipulation Attacks On A Power Grid, Srinidhi Madabhushi

Electronic Theses and Dissertations

An increased usage in IoT devices across the globe has posed a threat to the power grid. When an attacker has access to multiple IoT devices within the same geographical location, they can possibly disrupt the power grid by regulating a botnet of high-wattage IoT devices. Based on the time and situation of the attack, an adversary needs access to a fixed number of IoT devices to synchronously switch on/off all of them, resulting in an imbalance between the supply and demand. When the frequency of the power generators drops below a threshold value, it can lead to the generators …


Power System Frequency Control And Stability Analysis With Increasing Renewable Energy Penetration Level, Weihang Yan Jan 2020

Power System Frequency Control And Stability Analysis With Increasing Renewable Energy Penetration Level, Weihang Yan

Electronic Theses and Dissertations

With the ever-increasing penetration level of renewable energy generation units and the replacement of traditional synchronous generators, the issues associated with the deteriorated performance of power system frequency regulation and potential grid frequency instability become more significant. In this dissertation, the inertial control algorithms are investigated and analyzed for power electronics converter in a renewable energy generation unit. The concept and design of Virtual Synchronous Generator are comprehensively discussed, such that the small-signal stability and frequency stability of power systems with high renewable energy penetration level can be enhanced. Moreover, both nonlinear dynamic model and small-signal linearization of Virtual Synchronous …


Aggregated Der Management In Advanced Distribution Grids, Mohsen Mahoor Jan 2020

Aggregated Der Management In Advanced Distribution Grids, Mohsen Mahoor

Electronic Theses and Dissertations

Evolution of modern power systems are more distinct in distribution grids, where the growing integration of microgrids as well as distributed energy resources (DERs), including renewable energy resources, electric vehicles (EVs), and energy storage, poses new challenges and opportunities to grid management and operation. Rapid growth of distribution automation as well as equipment monitoring technologies in the distribution grids further offer new opportunities for distribution asset management. The idea of aggregated DERs is proposed as a remedy to streamline management and operation of advanced distribution grids, as discussed under three subjects in this dissertation. The first subject matter focuses on …


Connecting Offshore Floating Wind To The Western Electricity Grid: Transmission Options Decision Modeling, Bill Henry Jan 2020

Connecting Offshore Floating Wind To The Western Electricity Grid: Transmission Options Decision Modeling, Bill Henry

Engineering and Technology Management Student Projects

The purpose of this project is to obtain stakeholder views on a range of aspects relating to a proactive planning process to build transmission facilities in coordination with development of floating offshore wind (OSW) in southern Oregon and northern California. In the event that a transmission planning process to examine the potential need to assess and build transmission facilities to connect these wind resource areas is launched at a future date, the results of this study will assist planners by obtaining initial stakeholder views on the breadth of choices that should be considered, and more importantly, provide key insights on …


Experimental Evaluation Of Medium-Voltage Cascode Gallium Nitride (Gan) Devices For Bidirectional Dc–Dc Converters, Salah Salem H. Alharbi Jan 2020

Experimental Evaluation Of Medium-Voltage Cascode Gallium Nitride (Gan) Devices For Bidirectional Dc–Dc Converters, Salah Salem H. Alharbi

Electronic Theses and Dissertations

As renewable energy sources, such as photovoltaic (PV) cells and wind turbines, are rapidly implemented in DC microgrids, energy storage systems play an increasingly significant role in ensuring uninterrupted power supply and in supporting the reliability and stability of microgrid operations. Power electronics, especially bidirectional DC–DC converters, are essential parts in distributed energy storage and alternative energy systems because of their grid synchronization, DC power management, and bidirectional power flow capabilities. While there is increasing demand for more efficient, compact, and reliable power converters in numerous applications, most existing power converters are hindered by traditional silicon (Si) based semiconductors, which …


Edge-Cloud Computing For Iot Data Analytics: Embedding Intelligence In The Edge With Deep Learning, Ananda Mohon M. Ghosh, Katarina Grolinger Jan 2020

Edge-Cloud Computing For Iot Data Analytics: Embedding Intelligence In The Edge With Deep Learning, Ananda Mohon M. Ghosh, Katarina Grolinger

Electrical and Computer Engineering Publications

Rapid growth in numbers of connected devices including sensors, mobile, wearable, and other Internet of Things (IoT) devices, is creating an explosion of data that are moving across the network. To carry out machine learning (ML), IoT data are typically transferred to the cloud or another centralized system for storage and processing; however, this causes latencies and increases network traffic. Edge computing has the potential to remedy those issues by moving computation closer to the network edge and data sources. On the other hand, edge computing is limited in terms of computational power and thus is not well suited for …


Optimal Sizing Of Energy Storage With Embedded Wind Power Generation, Nicholas Roche, Jane Courtney Jan 2020

Optimal Sizing Of Energy Storage With Embedded Wind Power Generation, Nicholas Roche, Jane Courtney

Articles

Energy storage technologies are key to increased penetration of renewable energies on the distribution system. Not only do they increase availability of energy, but they contribute to the overall reliability of the system. However, the cost of large-scale storage systems can often be prohibitive, and storage needs to be sized appropriately, both to fill the energy gaps inevitable in renewable energies such as wind and to minimize costs. In this work, a Monte Carlo Simulation is performed to optimally size an energy storage system while minimizing overall system cost. 30 years of historical wind speed data are used to model …


Fault Identification On Electrical Transmission Lines Using Artificial Neural Networks, Christopher W. Asbery Jan 2020

Fault Identification On Electrical Transmission Lines Using Artificial Neural Networks, Christopher W. Asbery

Theses and Dissertations--Electrical and Computer Engineering

Transmission lines are designed to transport large amounts of electrical power from the point of generation to the point of consumption. Since transmission lines are built to span over long distances, they are frequently exposed to many different situations that can cause abnormal conditions known as electrical faults. Electrical faults, when isolated, can cripple the transmission system as power flows are directed around these faults therefore leading to other numerous potential issues such as thermal and voltage violations, customer interruptions, or cascading events. When faults occur, protection systems installed near the faulted transmission lines will isolate these faults from the …


Control Of A Grid-Tied Single-Phase Inverter For Renewable Energy Integration, Dianzhi Yu Jan 2020

Control Of A Grid-Tied Single-Phase Inverter For Renewable Energy Integration, Dianzhi Yu

All Graduate Theses, Dissertations, and Other Capstone Projects

With increasing demand for generating electricity from clean energy, renewable energy sources (RESs), such as wind and solar, has gained much attention due to the clean and quiet characteristics. In many applications, connecting multiple RESs of different types (e.g., wind and solar), voltages, and capacities to a power grid or load is required. Single- phase inverters have been widely installed in residential power system to meet the full or partial load demand. In this work, multiport converters were developed for integrating multiple RESs, wind turbine and photovoltaic (PV) panel. Since the intermittent characteristic of the RESs, an energy storage device, …


A Four-Port Dc-Dc Converter For A Hybrid Wind/Solar Energy System, Jiahong Ning Jan 2020

A Four-Port Dc-Dc Converter For A Hybrid Wind/Solar Energy System, Jiahong Ning

All Graduate Theses, Dissertations, and Other Capstone Projects

With the increasing demand for clean and hybrid energy in the last decades, more and more attentions are paid to the renewable energy, e.g., wind and solar energy. According to the International Energy Agency, solar power was growing-fastest source in the world. In a hybrid wind/solar system, power converters play an important role in in power management and the voltage regulation. Gradually, power systems have undergone a paradigm shift from centralized generation to distributed generation. Smart grid, which is a combination of power systems and communication networks, was proposed to allow power systems to fit the future system challenge. However, …


Virtual Impedance Based Decentralized Control For A Microgrid System, Ramkrishna Mishan Jan 2020

Virtual Impedance Based Decentralized Control For A Microgrid System, Ramkrishna Mishan

All Graduate Theses, Dissertations, and Other Capstone Projects

As greenhouse gases produced from the conventional power plant causes global climate change, using renewable energy sources (RESs) in the future power system is inevitable. To minimize greenhouse gases emission, the interest in renewable grid or micro-grid is growing nowadays. In the microgrid, especially in AC microgrids, converters play an important role in many areas, including microgrid integration, uninterrupted power supply, and flexible alternating current transmission systems. Inverter plays an essential role in grid integration because it serves the interface between the energy source and the power grid. The important aspect of the inverter is control. This thesis studies several …


Smart Distributed Generation System Event Classification Using Recurrent Neural Network-Based Long Short-Term Memory, Shuva Das Jan 2020

Smart Distributed Generation System Event Classification Using Recurrent Neural Network-Based Long Short-Term Memory, Shuva Das

College of Graduate Studies: Theses & Dissertations

High penetration of distributed generation (DG) sources into a decentralized power system causes several disturbances, making the monitoring and operation control of the system complicated. Moreover, because of being passive, modern DG systems are unable to detect and inform about these disturbances related to power quality in an intelligent approach. This paper proposed an intelligent and novel technique, capable of making real-time decisions on the occurrence of different DG events such as islanding, capacitor switching, unsymmetrical faults, load switching, and loss of parallel feeder and distinguishing these events from the normal mode of operation. This event classification technique was designed …


Lithium-Ion Battery And Beyond: Oxygen Vacancy Creation In Tungsten Trioxide And Surface Modification Of Lithium Metal, Rajesh Pathak Jan 2020

Lithium-Ion Battery And Beyond: Oxygen Vacancy Creation In Tungsten Trioxide And Surface Modification Of Lithium Metal, Rajesh Pathak

Electronic Theses and Dissertations

The graphite-based anode material has a low theoretical specific capacity of 371 mAh g-1. The transitional metal oxides (TMOs) are considered a better choice owing to their relatively higher specific capacity. Among TMOs, tungsten trioxide (WO3) is considered promising due to a higher specific capacity of 693 mAh g-1, low cost, mechanically stable, and eco-friendly. It has been a challenge to utilize the TMOs as anode materials as they suffer from poor electronic conductivity and large electrode volume expansion during discharge/charge cycles. In our first project, we demonstrate a unique self-recovery of capacity in reduced WO3 by the incorporation of …


Factors Affecting The Performance Of Photo-Voltaic Solar Energy Storage, Vasanth Bhat Jan 2020

Factors Affecting The Performance Of Photo-Voltaic Solar Energy Storage, Vasanth Bhat

Electronic Theses and Dissertations, 2020-2023

One of the most important factors in a nation's development is energy availability. All the aspects of its economy are directly proportional to the energy resources. Oil is one of the most sought energy resources currently. Solar energy is one of the most important renewable sources of energy available to us. With oil deposits depleting and current global warming, there is an emphasis on using more and more renewable sources or clean energy. This has led to immense research on solar cells and how it could better be used to get maximum output. Storage of energy is another aspect that …


Systematically Exploring The Effects Of Pole Count On The Performance And Cost Limits Of Ultrahigh Efficiency Fractional Hp Axial Flux Pm Machines, Narges Taran, Vandana Rallabandi, Greg Heins, Dan M. Ionel Jan 2020

Systematically Exploring The Effects Of Pole Count On The Performance And Cost Limits Of Ultrahigh Efficiency Fractional Hp Axial Flux Pm Machines, Narges Taran, Vandana Rallabandi, Greg Heins, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Optimizing the design of electric machines is a vital step in ensuring the economical use of active materials. The three-dimensional (3-D) flux paths in axial flux permanent magnet (AFPM) machines necessitate the use of computationally expensive 3-D electromagnetic analysis. Furthermore, a large number of design evaluations is required to find the optimum, causing the total computation time to be excessively long. In view of this, a two-level surrogate assisted algorithm capable of handling such expensive optimization problems is introduced, which substantially reduces the number of finite element analysis (FEA) evaluations to less than 200 while conventional algorithms require thousands of …


ระยะเวลาบำรุงรักษาที่เหมาะสมสำหรับเครื่องปรับอากาศแบบแยกส่วน, เชาวลิต คำสุข Jan 2020

ระยะเวลาบำรุงรักษาที่เหมาะสมสำหรับเครื่องปรับอากาศแบบแยกส่วน, เชาวลิต คำสุข

Chulalongkorn University Theses and Dissertations (Chula ETD)

งานวิจัยนี้มีวัตถุประสงค์เพื่อหาระยะเวลาที่เหมาะสมในการทำความสะอาดเครื่องปรับอากาศแบบแยกส่วน เนื่องจากประสิทธิภาพของเครื่องปรับอากาศที่ลดลงส่วนใหญ่มาจากสิ่งสกปรกที่เกาะติดที่แผงคอยล์เย็น และแผงคอยล์ร้อน ส่งผลให้ประสิทธิภาพของเครื่องปรับอากาศโดยรวมลดลง ดังนั้นการทำความสะอาดเครื่องปรับอากาศจะทำให้ประสิทธิภาพเพิ่มกลับคืนมาได้ในระดับหนึ่ง โดยประสิทธิภาพที่เพิ่มจะขึ้นอยู่กับความถี่ในการทำความสะอาดเครื่องปรับอากาศ ได้มีการศึกษาและจัดเก็บข้อมูลจากการเดินเครื่องปรับอากาศแบบแยกส่วนขนาดทำความเย็น 3.6 kW จำนวน 2 เครื่อง โดยมีการจัดเก็บข้อมูลในระยะเวลา 6 เดือน แยกประเภทการจัดเก็บข้อมูล เป็น 2 ประเภท คือ 1) เครื่องปรับอากาศเครื่องที่ 1 ล้างทำความสะอาดแล้วทำการเก็บข้อมูลทุกๆ 1 เดือน เป็นระยะเวลา 6 ครั้งโดยไม่ทำความสะอาดเพื่อหาการเสื่อมประสิทธิภาพเนื่องจากความสกปรก และ 2) เครื่องปรับอากาศเครื่องที่ 2 ล้างทำความสะอาดทุกเดือนทำให้เครื่องสะอาดอยู่เสมอเพื่อใช้ปรับแก้พลังไฟฟ้าเนื่องจากอุณหภูมิภายนอกที่เปลี่ยนไป และนำข้อมูลมาวิเคราะห์หาประสิทธิภาพ ซึ่งขึ้นกับตัวแปรอิสระที่ใช้ศึกษาคือ อุณหภูมิภายในห้องปรับอากาศ อุณหภูมิภายนอกห้อง ภาระทำความเย็น และความสกปรก การหาระยะเวลาที่เหมาะสมในการทำความสะอาดเครื่องปรับอากาศแบบแยกส่วนนั้น คิดจากราคาค่าใช้จ่ายต่ำสุดซึ่งประกอบด้วยค่าทำความสะอาดและค่าพลังงานไฟฟ้าที่เพิ่มขึ้นเนื่องจากความสกปรก จากการวิเคราะห์พบว่า อัตราการลดลงของประสิทธิภาพเครื่องปรับอากาศแบบแยกส่วน คือ ร้อยละ 3.01 ต่อเดือน และระยะเวลาที่เหมาะสมในการทำความสะอาดเครื่องปรับอากาศแบบแยกส่วน คือ ทุกๆ ระยะเวลา 3 เดือน


Optimization-Based Fast-Frequency Support In Low Inertia Power Systems, Ujjwol Tamrakar Jan 2020

Optimization-Based Fast-Frequency Support In Low Inertia Power Systems, Ujjwol Tamrakar

Electronic Theses and Dissertations

The future electrical energy demand will largely be met by non-synchronous renewable energy sources (RESs) in the form of photovoltaics and wind energy. The lack of inertial response from these non-synchronous, inverter-based generation in microgrids makes the system vulnerable to large rate-of-change-of-frequency (ROCOF) and frequency excursions. This can trigger under frequency load shedding and cause cascaded outages which may ultimately lead to total blackouts. To limit the ROCOF and the frequency excursions, fast-frequency support can be provided through appropriate control of energy storage systems (ESSs). For proper deployment of such fast-frequency control strategies, accurate information regarding the inertial response of …


Tailoring The Grain Boundaries Of Wide-Bandgap Perovskite Solar Cells By Molecular Engineering, Khalid Emshadi Jan 2020

Tailoring The Grain Boundaries Of Wide-Bandgap Perovskite Solar Cells By Molecular Engineering, Khalid Emshadi

Electronic Theses and Dissertations

Due to the attraction of fabricating highly efficient tandem solar cells, wide-bandgap perovskite solar cells have attracted substantial interest in recent years. However, polycrystalline perovskite thin-films show the existence of trap states at grain boundaries, which diminish the optoelectronic properties of the perovskite and thus remains a challenge. This research demonstrates a one-step solution-processing of the [MA0.9Cs0.1Pb(I0.6Br0.4)3] wide-bandgap perovskite using Phenylhydrazine Iodide with amino groups to successfully passivate the trap density within grain boundaries and increase the perovskite grain size. The reinforced morphology and grain boundaries treatment considerably enhanced the photovoltaic performance …


Enhanced Charge Carrier Dynamics And Defects Passivation In Hybrid Perovskite Solar Cell Using A Novel Organic Halide Salt, Md Ashuqur Rahman Laskar Jan 2020

Enhanced Charge Carrier Dynamics And Defects Passivation In Hybrid Perovskite Solar Cell Using A Novel Organic Halide Salt, Md Ashuqur Rahman Laskar

Electronic Theses and Dissertations

In the last few years, active research works on hybrid perovskite solar cells (HPSCs) have been going on throughout the world as a part of clean energy revolution. HPSCs have already proved their potentiality as future solar technology through their promising photovoltaic performances and ability for low temperature based solution processing. Nevertheless, still there are remaining challenges of better charge carrier dynamics and defects minimization in HPSCs. Overcoming these challenges are very important to achieve high power conversion efficiency (PCE) practically. Aiming this, a novel organic halide salt called Phenylhydrazinium Iodide (PHAI) is introduced as additive with CH3NH …


Surface And Structure Engineering For Next Generation Lithium Metal Batteries, Ke Chen Jan 2020

Surface And Structure Engineering For Next Generation Lithium Metal Batteries, Ke Chen

Electronic Theses and Dissertations

Lithium (Li) metal has been considered as one of the most promising anode materials to replace conventional graphite for Li-ion battery due to its high theoretical capacity (3860 mAh g-1) and low electrochemical potential (-3.04 V vs standard hydrogen electrode). However, it still faces some problems such as unstable solid electrolyte interphase (SEI), uncontrolled Li dendrites growth, and infinite volume change during battery charging/discharging. To develop a stable and low-cost Li metal anode for next-generation Li metal battery, in this dissertation, we have made efforts to understand and solve these problems in two aspects, by introducing an artificial SEI and …


A Four-Port Bidirectional Dc-Dc Converter For Renewable Energy System And Microgrid, Xia Du Jan 2020

A Four-Port Bidirectional Dc-Dc Converter For Renewable Energy System And Microgrid, Xia Du

All Graduate Theses, Dissertations, and Other Capstone Projects

Renewable energy has nowadays become important in electrical power applications. Power converters play an important role in integrating these distributed energy sources. However, due to their intermittence characteristics, e.g., the output power provided by the PV and wind turbine is not stable, either an energy storage system will be used or microgrid is formed between the main grid and the sources. To integrate these renewable energy sources and manage the power flow, a multiport converter is preferred because it is highly beneficial and cost-efficiently than the traditional solution that using multiple individual power converter for each source. This thesis proposed …


การประเมินผลระบบไฟฟ้าพลังงานแสงอาทิตย์และแบตเตอรี่แบบวีอาร์เอฟภายหลังการติดตั้งสำหรับการรักษาเสถียรภาพและลดค่าไฟฟ้า : กรณีศึกษาโรงพยาบาลทั่วไป, ธีระศักดิ์ วาทโยธา Jan 2020

การประเมินผลระบบไฟฟ้าพลังงานแสงอาทิตย์และแบตเตอรี่แบบวีอาร์เอฟภายหลังการติดตั้งสำหรับการรักษาเสถียรภาพและลดค่าไฟฟ้า : กรณีศึกษาโรงพยาบาลทั่วไป, ธีระศักดิ์ วาทโยธา

Chulalongkorn University Theses and Dissertations (Chula ETD)

โดยทั่วไปการติดตั้งระบบผลิตไฟฟ้าจากเซลล์แสงอาทิตย์และแบตเตอรี่เพื่อสำรองไฟฟ้านั้น มักจะมีการประเมินโครงการก่อนการติดตั้งเสมอ ในส่วนของงานศึกษานี้จะเป็นการประเมินผลการทำงานที่เกิดขึ้นภายหลังการติดตั้งระบบผลิตไฟฟ้าจากเซลล์แสงอาทิตย์บนหลังคาของโรงพยาบาล เพื่อลดภาระค่าใช้จ่ายด้านพลังงานไฟฟ้าและการนำแบตเตอรี่ Vanadium Redox Flow (VRF) มาใช้ในการรักษาเสถียรภาพของระบบไฟฟ้า ซึ่งโรงพยาบาลที่ศึกษาตั้งอยู่ในพื้นที่ห่างไกลสภาพพื้นที่เป็นภูเขาสูง อยู่ในพื้นที่ปลายระบบสายส่งจึงมีเหตุการณ์ไฟตกไฟดับบ่อย รวมทั้งมีภาระค่าใช้จ่ายด้านพลังงานไฟฟ้าที่สูง โรงพยาบาลจึงได้ติดตั้งระบบผลิตไฟฟ้าจากเซลล์แสงอาทิตย์บนหลังคาเพื่อลดค่าใช้จ่ายด้านพลังงานไฟฟ้าและนำแบตเตอรี่มาใช้กักเก็บพลังงานเพื่อสำรองในยามฉุกเฉินกรณีการเกิดไฟตกไฟดับ โดยแบตเตอรี่จะจ่ายไฟในส่วนที่สำคัญคือ ห้องฉุกเฉิน ห้อง Lab ห้องคลอด ห้องผ่าตัด ในการศึกษาจะทำการจัดเก็บข้อมูลจากระบบตรวจวัดและบริหารจัดการพลังงานภายในอาคารของโรงพยาบาลผ่านระบบออนไลน์ ได้แก่ ข้อมูลผลการผลิตไฟฟ้าจากเซลล์แสงอาทิตย์ ความเข้มแสงอาทิตย์ สถานะการทำงานของแบตเตอรี่ และปริมาณการใช้ไฟฟ้าของโรงพยาบาล ตั้งแต่เดือน พฤษภาคม 2561 ถึงเดือน เมษายน 2562 จากการศึกษาพบว่า ระบบผลิตไฟฟ้าจากเซลล์แสงอาทิตย์สามารถผลิตไฟฟ้าได้ 175,255.1 kWh/ปี สามารถประหยัดค่าไฟฟ้าที่อัตราค่าไฟเฉลี่ยที่ 4.04 บาท คิดเป็นเงินประมาณ 708,030 บาท คิดเป็นผลประหยัดพลังงานเทียบเท่าพันตันน้ำมันดิบได้เท่ากับ 0.0151 (ktoe/ปี) ซึ่งช่วยลดค่าใช้จ่ายด้านพลังงานไฟฟ้าของโรงพยาบาลได้ประมาณ 56.2% ของความต้องการใช้ไฟฟ้าในช่วงเวลาดังกล่าว และระบบกักเก็บพลังงานของแบตเตอรี่มีวงรอบการชาร์จและดิสชาร์จทั้งหมด 115 ครั้ง ซึ่งหมายถึงมีเหตุการณ์ไฟตกไฟดับจำนวน 115 ครั้ง โดยแบตเตอรี่จะทำงานอย่างต่อเนื่องทันทีโดยไม่รู้สึกว่าเกิดไฟตกหรือไฟดับ สามารถช่วยรักษาเสถียรภาพทางไฟฟ้าให้เกิดความมั่นคงทางไฟฟ้า ในห้องที่มีความสำคัญ ในกรณีไฟตกไฟดับ เพื่อไม่ให้เกิดความเสียหายต่ออุปกรณ์ทางการแพทย์ ยาหรือวัคซีน รวมทั้งการรักษาในกรณีฉุกเฉินได้อย่างต่อเนื่อง