Evaluation Of Bearing Voltage Reduction In Electric Machines By Using Insulated Shaft And Bearings,
2020
University of Kentucky
Evaluation Of Bearing Voltage Reduction In Electric Machines By Using Insulated Shaft And Bearings, Peng Han, Greg Heins, Dean Patterson, Mark Theile, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Bearing voltages and corresponding currents in electric machines driven by pulse width modulation (PWM) converters with fast switching and high dv/dt can cause premature bearing failures. This paper evaluates the bearing voltage reduction by using insulated shafts and bearings. An equivalent circuit representation of electric machines taking into account high-frequency effects is developed to show the production mechanism of bearing voltage, based on which simulations are performed with detailed finite element models for transient and simplified equivalent circuit for steady-state analysis. The steady-state equivalent circuit is then calibrated, by combined numerical calculations and experimental measurements, and used to predict the …
Combined Numerical And Experimental Determination Of Ball Bearing Capacitances For Bearing Current Prediction,
2020
University of Kentucky
Combined Numerical And Experimental Determination Of Ball Bearing Capacitances For Bearing Current Prediction, Peng Han, Greg Heins, Dean Patterson, Mark Theile, Dan M. Ionel
Electrical and Computer Engineering Faculty Publications
High-frequency voltages across the steel ball bearings and the corresponding currents can cause premature bearing failures in electric machines driven by PWM converters. The bearing voltage, one of the most commonly-used failure indicators, depends heavily on the bearing capacitance. This paper presents a combined numerical and experimental approach for the calculation of ball bearing capacitances to address the uncertainty introduced by lubricant property, lubrication status and other metal parts, such as seals and ball retainers. Based on the obtained capacitance breakdown, the influences of temperature, speed and bearing load (radial, axial or combined) on the capacitance are studied. Measurements and …
Trust-Based User Interface Design For Islanded Alternating Current Microgrids,
2020
University of New Mexico - Main Campus
Trust-Based User Interface Design For Islanded Alternating Current Microgrids, Yuliya Matlashova
Electrical and Computer Engineering ETDs
Futuristic microgrid systems may be capable of providing extensive information to the operator. As microgrid systems become more pervasive there will be a need to adjust the information an operator requires, to provide an optimized user-interface. In this paper, a combinatorial optimization strategy is used to provide an optimal user-interface for the microgrid operator that selects information for display depending on the operator's trust level in the system, and the assigned task. We employ a method based in sensor placement by capturing elements of the interface as different sensors, that find an optimal set of sensors via combinatorial optimization. However, …
Electric Drives With Wide Bandgap Devices For Two-Phase Very Low Inductance Machines,
2020
University of Kentucky
Electric Drives With Wide Bandgap Devices For Two-Phase Very Low Inductance Machines, Yibin Zhang, Damien Lawhorn, Peng Han, Aaron M. Cramer, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Slotless and coreless machines with low inductance and low core losses are attractive for high speed and high power density applications. With the increase in fundamental frequency, typical drive implementations using conventional silicon-based devices are performance limited and also produce large current and torque ripples. This paper presents a systematic study of proposed drive configurations implemented with wide bandgap (WBG) devices in order to mitigate such issues for 2-phase very low inductance machines. Two inverter topologies, i.e., a dual H-bridge inverter with maximum redundancy and survivability and a 3-leg inverter for reduced cost, are considered. Feasible modulation schemes are derived …
Optimal Study Of A High Specific Torque Vernier-Type Axial-Flux Pm Machine With Two Different Stators And A Single Winding,
2020
University of Kentucky
Optimal Study Of A High Specific Torque Vernier-Type Axial-Flux Pm Machine With Two Different Stators And A Single Winding, Murat G. Kesgin, Peng Han, Narges Taran, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
This paper presents the optimal study of a verniertype axial-flux permanent-magnet (AFPM) machine, which has a high-polarity spoke-type PM rotor, a wound stator with a low number of coils, and a profiled stator. Both stators have profiled teeth to enhance the magnetic interaction between the rotor PM array and stator windings for torque production. Compared to the topology with two wound stators, the studied one has a smaller total axial length and is expected more suitable for applications where the space is limited in axial direction. Both topologies are optimized through 3-dimensional (3D) finite element analysis (FEA) by the combined …
Demand Response Of Hvacs In Large Residential Communities Based On Experimental Developments,
2020
University of Kentucky
Demand Response Of Hvacs In Large Residential Communities Based On Experimental Developments, Huangjie Gong, Evan S. Jones, Rosemary E. Alden, Andrew G. Frye, Donald G. Colliver, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Heating, ventilation, and air-conditioning (HVAC) systems contribute the largest electricity usage for a residential community. Modeling of the HVAC systems facilitate the study of demand response (DR) at both the residential and the power system level. In this paper, the equivalent thermal model of a reference house was proposed. Parameters for the reference house were determined based on the systematic study of experimental data obtained from fully instrumented field demonstrators. The aggregated HVAC load was modeled based on the reference house while considering a realistic distribution of HVAC parameters derived from data that was provided by one of the largest …
Electric Power System Studies For A Multi-Mw Pv Farm And Large Rural Community With Net Zero Energy And Microgrid Capabilities,
2020
University of Kentucky
Electric Power System Studies For A Multi-Mw Pv Farm And Large Rural Community With Net Zero Energy And Microgrid Capabilities, Evan S. Jones, Oluwaseun M. Akeyo, Keith Waters, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Solar photovoltaic (PV) systems are currently being deployed at an accelerated rate because of their cost-competitiveness and environmental benefits, which make them a prime candidate for local renewable energy generation in communities. Microgrids can help accommodate for the problems that accompany PV systems, such as intermittency due to weather, by coordinating different distributed energy resources (DERs), while islanded or by drawing power from the utility while in grid-connected mode. An islanding option is also important for resilience and grid fault mitigation, even if other DERs are not present within the system. This paper studies the potential benefits that a multi-MW …
Design Optimization Of Coreless Axial-Flux Pm Machines With Litz Wire And Pcb Stator Windings,
2020
University of Kentucky
Design Optimization Of Coreless Axial-Flux Pm Machines With Litz Wire And Pcb Stator Windings, Murat G. Kesgin, Peng Han, Narges Taran, Damien Lawhorn, Donovin Lewis, Dan M. Ionel
Electrical and Computer Engineering Faculty Publications
Coreless axial-flux permanent-magnet (AFPM) machines may be attractive options for high-speed and high-power-density applications due to the elimination of core losses. In order to make full use of the advantages offered by these machines and avoid excessive eddy current losses in windings, advanced technologies for winding conductors need to be employed to suppress the eddy effect, such as the Litz wire and printed circuit board (PCB). In this paper, the best practices for designing Litz wire/PCB windings are discussed and a brief survey of state of the art PCB winding technology is provided. Three coreless AFPM machines are mainly considered. …
On-Chip Nonreciprocal Components For Full-Duplex Communications And Gaussian Regulated Gate Driver For Electromagnetic Interference Reduction,
2020
Southern Methodist University
On-Chip Nonreciprocal Components For Full-Duplex Communications And Gaussian Regulated Gate Driver For Electromagnetic Interference Reduction, Chang Yang
Electrical Engineering Theses and Dissertations
This dissertation is comprised of two unrelated design endeavors. The first one is about two CMOS nonreciprocal components: 1) an isolator and 2) a circulator. To make the components compact enough for the next generation communication systems with wide bandwidth, both components operate at 100 GHz band for full-duplex transceivers for ultra-high-data-rate millimeter-wave wireless communication. The proposed nonreciprocal structures are based on a time-domain modulation by signals at around 1/6 of the RF frequencies and spatial duplexing over the RF signal paths, demonstrating over 45 dB isolation in a bandwidth of 1.5 GHz over the tuning range of 85-110 GHz. …
Non-Conventional Vehicles As A Way Towards Carbon Neutrality In Iceland,
2020
SIT Study Abroad
Non-Conventional Vehicles As A Way Towards Carbon Neutrality In Iceland, Julia Sokolowska
Independent Study Project (ISP) Collection
Paris Agreement’s chief objective is to protect the Earth and its inhabitants from a point of no return, when the effects of climate change will be so intense that they will shift the equilibrium of ecosystems. The distinctiveness of this international environmental treaty is that it does not impose climate change mitigation measures, but rather allows nation states to create their own set of measures, the NDCs, to reach the global warming of ‘well below 2oC’ by the end of the century. Thus, Iceland has submitted its own NDC, the Climate Action Plan 2018-2030, which has an ambitious goal of …
Survey Of Dc-Dc Non-Isolated Topologies For Unidirectional Power Flow In Fuel Cell Vehicles,
2020
Prince Sultan University, Saudi Arabia
Survey Of Dc-Dc Non-Isolated Topologies For Unidirectional Power Flow In Fuel Cell Vehicles, Mahajan Sagar Bhaskar, Vigna K. Ramachandaramurthy, Sanjeevikumar Padmanaban, Frede Blaabjerg, Dan M. Ionel, Massimo Mitolo, Dhafer Almakhles
Power and Energy Institute of Kentucky Faculty Publications
The automobile companies are focusing on recent technologies such as growing Hydrogen (H2) and Fuel Cell (FC) Vehicular Power Train (VPT) to improve the Tank-To-Wheel (TTW) efficiency. Benefits, the lower cost, `Eco' friendly, zero-emission and high-power capacity, etc. In the power train of fuel cell vehicles, the DC-DC power converters play a vital role to boost the fuel cell stack voltage. Hence, satisfy the demand of the motor and transmission in the vehicles. Several DC-DC converter topologies have proposed for various vehicular applications like fuel cell, battery, and renewable energy fed hybrid vehicles etc. Most cases, the DC-DC power converters …
Modified Fractional Order Sliding Mode Control For Speed Control Of Permanent Magnet Synchronous Motor,
2020
Universiti Malaya
Modified Fractional Order Sliding Mode Control For Speed Control Of Permanent Magnet Synchronous Motor, Fardila Mohd Zaihidee
Student Works (2020-2029)
In recent years, energy saving research activities have focused on electric motors and their systems since they are the main consumer of electricity in the industrial sector. Permanent magnet synchronous motor is known as a high-efficiency motor and slowly replacing induction motors in the industries. For speed control of PMSM, the sliding mode controller (SMC) has been widely used due to its robustness, high accuracy, and simplicity. The main disadvantage of the SMC method is the chattering phenomenon, which should be reduced or eliminated without compromising the controller’s robustness. Fractional order sliding mode speed control (FOSMC) of PMSM is proposed …
Design And Experiment Of A Sun-Powered Smart Building Envelope With Automatic Control,
2020
Columbia University
Design And Experiment Of A Sun-Powered Smart Building Envelope With Automatic Control, Qiliang Lin, Yanchu Zhang, Arnaud Van Mieghem, Yi-Chung Chen, Nanfang Yu, Yuan Yang, Huiming Yin
Electrical and Computer Engineering Faculty Research
A novel sun-powered smart window blind (SPSWB) system has been designed and developed for the smart control of building envelopes to achieve the optimal internal comfort with minimum energy expenditure. Its self-powered sensing, controlling, and actuation significantly simplify the installation and maintenance of the system. The energy is harvested by the attached thin-film photovoltaic cells, after which it is voltage-regulated for the permanent storage into a rechargeable battery with 55% energy efficiency. The excessive heat absorbed by the solar cells is dissipated by a PVdF-HFP porous coating with more than 9% temperature reduction. The smart control of the energy harvesting …
Optimal Distribution System Reconfiguration Incorporating Distributed Generation Based On Simplified Network Approach,
2020
Universiti Malaya
Optimal Distribution System Reconfiguration Incorporating Distributed Generation Based On Simplified Network Approach, Mohammad Al Samman
Student Works (2020-2029)
Network Reconfiguration (NR) and Distributed Generation (DG) are well-accepted strategies to minimize power loss and voltage deviation in the Electrical Distribution Network (EDN). Since the NR problem contains a huge combinational search space, most researchers applied meta-heuristic methods to attain optimal NR solution. However, meta-heuristic methods do not always guarantee optimal solution and furthermore they consume huge processing time. This occurs mainly due to (1) random solution’s initialization and (2) the verification of solution in each iteration to fulfill the operation constraints during the optimization process. Besides, solving the NR problem simultaneously with DG placement and sizing increases the computational …
Lstm Forecasts For Smart Home Electricity Usage,
2020
University of Kentucky
Lstm Forecasts For Smart Home Electricity Usage, Rosemary E. Alden, Huangjie Gong, Cristinel Ababei, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
With increasing of distributed energy resources deployment behind-the-meter and of the power system levels, more attention is being placed on electric load and generation forecasting or prediction for individual residences. While prediction with machine learning based approaches of aggregated power load, at the substation or community levels, has been relatively successful, the problem of prediction of power of individual houses remains a largely open problem. This problem is harder due to the increased variability and uncertainty in user consumption behavior, which make individual residence power traces be more erratic and less predictable. In this paper, we present an investigation of …
The Effect Of High Efficiency Building Technologies And Pv Generation On The Energy Profiles For Typical Us Residences,
2020
University of Kentucky
The Effect Of High Efficiency Building Technologies And Pv Generation On The Energy Profiles For Typical Us Residences, Evan S. Jones, Rosemary E. Alden, Huangjie Gong, Andrew G. Frye, Donald G. Colliver, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
The penetrations of high efficiency technologies and photovoltaic (PV) generation are increasing in the residential sector. Technologies such as improved insulation and efficient HVAC systems significantly affect the energy profile of a house. This effect varies due to climate characteristics, i.e. temperature, solar radiation, relative humidity, and wind speeds. The effect of other technologies, such as efficient water heaters, lighting, or kitchen appliances, is mainly governed by human behavior, which may be represented by a schedule. This paper studies the performance of both climate-influenced and scheduled household devices among different levels of efficiency through combined computational and experimental methods. Three …
On The Feasibility Of Electrification For Large Mobile Cranes,
2020
University of Kentucky
On The Feasibility Of Electrification For Large Mobile Cranes, Donovin Lewis, Damien Lawhorn, Dan M. Ionel
Power and Energy Institute of Kentucky Faculty Publications
Trends towards vehicle electrification to reduce dependence on fossil fuels and increase drive train efficiency have led vehicle manufacturers to seek out paths towards gradual hybridization. For heavy duty construction vehicles, electrification consists of two principle components: electric hybridization of the vehicle carrier and the vehicle's auxiliary function. Economic and physical feasibility for the transition to electrical replacements for critical system components is important for the gradual development of electrified systems. In this paper, we present an investigation into multiple pathways for the hybridization of mobile cranes paired with simulations that analyze the feasibility of system electrification. ADVISOR was used …
Cost Analysis Of Optimized Islanded Energy Systems In A Dispersed Air Base Conflict,
2020
Air Force Institute of Technology
Cost Analysis Of Optimized Islanded Energy Systems In A Dispersed Air Base Conflict, Jay F. Pearson, Torrey J. Wagner, Justin D. Delorit
Faculty Publications
The United States Air Force has implemented a dispersed air base strategy to enhance mission effectiveness for near-peer conflicts. Asset dispersal places many smaller bases across a wide geographic area, which increases resupply requirements and logistical complexity. Hybrid energy systems reduce resupply requirements through sustainable, off-grid energy production. This paper presents a novel hybrid energy renewable delivery system (HERDS) model capable of (1) selecting the optimal hybrid energy system design that meets demand at the lowest net present cost and (2) optimizing the delivery of the selected system using existing Air Force cargo aircraft. The novelty of the model’s capabilities …
Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries,
2020
1. State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China;2. University of Louisiana at Lafayette, Lafayette, LA 70504, USA;
Recent Progress In Bifunctional Catalysts For Zinc-Air Batteries, Neng-Neng Xu, Jin-Li Qiao
Journal of Electrochemistry
Zinc-air battery has attracted great attention from researchers due to its high energy density and power density, which is expected to be widely used in energy conversion and storage. Air electrode as the core area of oxygen catalytic reaction is the focus of the entire zinc-air battery research. Recently, many research achievements have been made in non-noble metal bifunctional catalysts/electrodes with high activity, low cost and abundant species. In this review, we mainly focus on the reaction mechanism and the recent progress in non-noble metal oxide catalyst, carbon-based catalyst, and carbon-based transition metal compound composite and self-supporting electrode. In addition, …
Research Progress Of Metal-Nitrogen-Carbon Catalysts Toward Oxygen Reduction Reaction Inm Changchun Institute Of Applied Chemistry,
2020
1. State Key Laboratory of Electroanalytica Chemistry, Changchun Institute of Applied Chemistry,Chinese Academy of Sciences University of Chinese Academy of Sciences, Changchun 130022,Jilin, China;2. University of Science and Technology of China, School of Applied Chemistry & Engineering, Hefei 230026, Anhui, China;
Research Progress Of Metal-Nitrogen-Carbon Catalysts Toward Oxygen Reduction Reaction Inm Changchun Institute Of Applied Chemistry, Ming-Jun Xu, Jie Liu, Jun-Jie Ge, Chang-Peng Liu, Wei Xing
Journal of Electrochemistry
The development of highly active and stable catalysts toward oxygen reduction reaction (ORR) has been facing severe challenges. In recent years, pyrolytic M-N-C catalysts and metal-organic framework derived materials made the performance of non-noble metal catalysts greatly improved, however, the molecular and atomic level understanding in the reaction active sites and the mechanism are still lacking. Here, we summarize the recent research progress made in the Changchun Institute of Applied Chemistry. We present a microporous metal-organic-framework confined strategy toward the preferable formation of ORR catalysts. Firstly, we studied the active site and proposed a new active site structure for the …
