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Electrical and Computer Engineering Commons™

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Power and Energy

University of Kentucky

Power and Energy Institute of Kentucky Faculty Publications

2018

Articles 1 - 15 of 15

Full-Text Articles in Electrical and Computer Engineering

Optimal Design Of A Switched Reluctance Motor With Magnetically Disconnected Rotor Modules Using A Design Of Experiments Differential Evolution Fea-Based Method, Vandana Rallabandi, Jie Wu, Ping Zhou, David G. Dorrell, Dan M. Ionel Nov 2018

Optimal Design Of A Switched Reluctance Motor With Magnetically Disconnected Rotor Modules Using A Design Of Experiments Differential Evolution Fea-Based Method, Vandana Rallabandi, Jie Wu, Ping Zhou, David G. Dorrell, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Switched reluctance (SR) machines are attractive because they present relatively high efficiency and torque density in spite of lacking permanent magnets. This paper focuses on a two-objective optimization of an external rotor SR motor with a stator that has concentrated coils and a rotor with magnetically isolated modules. The objectives are minimum loss and mass, and 11 independent dimensionless geometric variables are considered as inputs that affect them. A combined design of experiments (DOE) and differential evolution (DE) approach is proposed. The DOE methodology is used to reduce the search space by eliminating from consideration input variable values, leading to …

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Two-Level Surrogate-Assisted Differential Evolution Multi-Objective Optimization Of Electric Machines Using 3-D Fea, Narges Taran, Dan M. Ionel, David G. Dorrell Nov 2018

Two-Level Surrogate-Assisted Differential Evolution Multi-Objective Optimization Of Electric Machines Using 3-D Fea, Narges Taran, Dan M. Ionel, David G. Dorrell

Power and Energy Institute of Kentucky Faculty Publications

A two-level surrogate-assisted optimization algorithm is proposed for electric machine design using 3-D finite-element analysis (FEA). The algorithm achieves the optima with much fewer FEA evaluations than conventional methods. It is composed of interior and exterior levels. The exploration is performed mainly in the interior level, which evaluates hundreds of designs employing affordable kriging models. Then, the most promising designs are evaluated in the exterior loop with expensive 3-D FEA models. The sample pool is constructed in a self-adjustable and dynamic way. A hybrid stopping criterion is used to avoid unnecessary expensive function evaluations.

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Simulation Studies For A Multi-Mw Hybrid Wind-Solar Pv System For Desalination Plants, Vandana Rallabandi, Nasser Alawhali, Oluwaseun M. Akeyo, Dan M. Ionel Oct 2018

Simulation Studies For A Multi-Mw Hybrid Wind-Solar Pv System For Desalination Plants, Vandana Rallabandi, Nasser Alawhali, Oluwaseun M. Akeyo, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

This paper presents a power system configuration and control schemes for a Multi-MW wind-solar hybrid system, which includes multiple wind turbines and solar panels to support a desalination plant. The wind and solar systems are sized such that the desalination plant obtains, as far as possible, its power from the renewable sources, to minimize the dependence on the utility grid. Each section of the wind turbine system includes a variable speed permanent magnet synchronous generator connected to the grid via a back-to-back voltage source converter. The rectifier operates the wind system at the maximum power point, and the inverter provides …

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Real Time Operation Of Smart Homes With Pv And Battery Systems Under Variable Electricity Rate Schedules And Transactive Power Flow, Huangjie Gong, Oluwaseun M. Akeyo, Vandana Rallabandi, Dan M. Ionel Oct 2018

Real Time Operation Of Smart Homes With Pv And Battery Systems Under Variable Electricity Rate Schedules And Transactive Power Flow, Huangjie Gong, Oluwaseun M. Akeyo, Vandana Rallabandi, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

According to some utility schedules, the electricity rate is variable such that homes may be encouraged to buy and store power in a battery when it is inexpensive, and self-consume or sell to the grid during other times. Power arbitrage through a battery energy storage (BES), can help maintain consumer comfort and minimize residential electricity bills. This paper reports the calculated daily energy costs incurred by different types of homes for a given utility electricity rate schedule. The homes exchange power among each other behind a section of the distribution network. A free market system is formed and the electricity …

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Power Utility Tests For Multi-Mw High Energy Batteries, Oluwaseun M. Akeyo, Huangjie Gong, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel Oct 2018

Power Utility Tests For Multi-Mw High Energy Batteries, Oluwaseun M. Akeyo, Huangjie Gong, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

This paper reviews the procedures, layouts and metrics described in the new test manual issued by the Electric Power Research Institute (EPRI), in order to determine the performance and functionality of a utility scale battery energy storage system (BESS). In this approach, the large battery unit is connected to the dc-link of a bidirectional power conversion system (PCS), which may be interfaced with either the utility grid or a load bank for the purpose of estimating the BESS operation and performance characteristics, some of which includes; available charge/discharge energy at rated power, continuous charge/discharge duration, battery ramp rate, and ac …

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Transistor-Clamped Multilevel H-Bridge Inverter In Si And Sic Hybrid Configuration For High-Efficiency Photovoltaic Applications, Yibin Zhang, Jiangbiao He, Sanjeevikumar Padmanaban, Dan M. Ionel Sep 2018

Transistor-Clamped Multilevel H-Bridge Inverter In Si And Sic Hybrid Configuration For High-Efficiency Photovoltaic Applications, Yibin Zhang, Jiangbiao He, Sanjeevikumar Padmanaban, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Using wide bandgap (WBG) devices has been a promising solution to improve the efficiency of power inverters for photovoltaic (PV) applications. However, for multilevel inverters, using WBG devices to improve the inverter efficiency can increase the system cost dramatically due to the high price of WBG devices in the present market as well as the large number of power devices typically required in multilevel inverter topologies. In this paper, a five-level transistor clamped H-bridge (TCHB) inverter will be further investigated. This inverter requires much lower number of semiconductor switches and fewer isolated dc sources than the conventional cascaded H-bridge inverter. …

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Torque Production Capability Of Axial Flux Machines With Single And Double Rotor Configurations, Narges Taran, Greg Heins, Vandana Rallabandi, Dean Patterson, Dan M. Ionel Sep 2018

Torque Production Capability Of Axial Flux Machines With Single And Double Rotor Configurations, Narges Taran, Greg Heins, Vandana Rallabandi, Dean Patterson, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Axial flux PM (AFPM) machines are used particularly in applications requiring a compact structure. Their disc shape topology and axial air-gap have lead to a variety of configurations including two popular ones: the yokeless and segmented armature (YASA), and the single-stator single-rotor or single sided machine. In this study, a comprehensive comparative analysis of these configurations is conducted at different magnetic and electric loadings. It is found that at lower loadings, typically employed for air-cooled machines, the torque/ampere characteristics of the YASA machine are almost identical to those of a single sided machine constructed with half the magnet volume. On …

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Improving The Capacity Factor And Stability Of Multi-Mw Grid Connected Pv Systems With Results From A 1mw/2mwh Battery Demonstrator, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel Sep 2018

Improving The Capacity Factor And Stability Of Multi-Mw Grid Connected Pv Systems With Results From A 1mw/2mwh Battery Demonstrator, Oluwaseun M. Akeyo, Vandana Rallabandi, Nicholas Jewell, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Conventional PV systems integrated with a battery connect the array and the energy storage unit to a dc-link through individual dc-dc converters for maximum power point tracking (MPPT) and battery charge control. This paper proposes a new system configuration, which connects the PV array and battery unit to the dc-link of the system inverter via a single dc-dc converter capable of simultaneously operating as a charge controller and MPPT device. This dc-dc converter is controlled such that it charges/discharges the battery with the amount of power required to maintain the PV array at its MPPT reference voltage. The proposed system …

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Exploring The Efficiency And Cost Limits Of Fractional Hp Axial Flux Pm Machine Designs, Narges Taran, Vandana Rallabandi, Greg Heins, Dan M. Ionel Sep 2018

Exploring The Efficiency And Cost Limits Of Fractional Hp Axial Flux Pm Machine Designs, 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 flux paths in axial flux PM (AFPM) machines necessitate the use of computationally expensive 3D 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 FEA evaluations. The proposed algorithm is employed to optimally design an AFPM machine within a specified envelope, …

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Net Zero Energy Houses With Dispatchable Solar Pv Power Supported By Electric Water Heater And Battery Energy Storage, Huangjie Gong, Vandana Rallabandi, Dan M. Ionel, Donald G. Colliver, Shaun Duerr, Cristinel Ababei Sep 2018

Net Zero Energy Houses With Dispatchable Solar Pv Power Supported By Electric Water Heater And Battery Energy Storage, Huangjie Gong, Vandana Rallabandi, Dan M. Ionel, Donald G. Colliver, Shaun Duerr, Cristinel Ababei

Power and Energy Institute of Kentucky Faculty Publications

Over a year, net zero energy (NZE) houses produce and feed zero net metered electrical energy to the grid. Technical challenges, notably the `duck curve' arise due to the fact that peak solar generation and load demand are seldom coincident. Common approaches to mitigate this limitation include the curtailment of solar power, and the use of storage. Surplus solar energy may be stored in a battery, which can subsequently be discharged to supply the home electricity needs when demand is in excess. In addition to batteries, less expensive electric water heaters, which are ubiquitous, can be modified as energy storage …

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Hybrid Pv-Wind, Micro-Grid Development Using Quasi-Z-Source Inverter Modeling And Control—Experimental Investigation, Neeraj Priyadarshi, Sanjeevikumar Padmanaban, Dan M. Ionel, Lucian Mihet-Popa, Farooque Azam Aug 2018

Hybrid Pv-Wind, Micro-Grid Development Using Quasi-Z-Source Inverter Modeling And Control—Experimental Investigation, Neeraj Priyadarshi, Sanjeevikumar Padmanaban, Dan M. Ionel, Lucian Mihet-Popa, Farooque Azam

Power and Energy Institute of Kentucky Faculty Publications

This research work deals with the modeling and control of a hybrid photovoltaic (PV)-Wind micro-grid using Quasi Z-source inverter (QZsi). This inverter has major benefits as it provides better buck/boost characteristics, can regulate the phase angle output, has less harmonic contents, does not require the filter and has high power performance characteristics over the conventional inverter. A single ended primary inductance converter (SEPIC) module used as DC-DC switched power apparatus is employed for maximum power point tracking (MPPT) functions which provide high voltage gain throughout the process. Moreover, a modified power ratio variable step (MPRVS) based perturb & observe (P&O) …

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Coreless And Conventional Axial Flux Permanent Magnet Motors For Solar Cars, Narges Taran, Vandana Rallabandi, Greg Heins, Dan M. Ionel Jul 2018

Coreless And Conventional Axial Flux Permanent Magnet Motors For Solar Cars, Narges Taran, Vandana Rallabandi, Greg Heins, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Axial flux permanent magnet (AFPM) motors are suitable options for solar-powered vehicles due to their compact structure and high torque density. Furthermore, certain types of AFPM machines may be configured without stator cores, which eliminates associated losses and cogging torque and simplifies the manufacturing and assembly. This paper examines two machine designs for use in the solar-powered vehicle of the challenger class-a single rotor, single stator conventional AFPM machine, and a coreless AFPM machine with multiple stator and rotor disks. The response surface methodology (RSM) is utilized for the systematic comparison of the conventional and coreless topologies and to select …

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Power Electronics Powertrain Architectures For Hybrid And Solar Electric Airplanes With Distributed Propulsion, Damien Lawhorn, Vandana Rallabandi, Dan M. Ionel Jul 2018

Power Electronics Powertrain Architectures For Hybrid And Solar Electric Airplanes With Distributed Propulsion, Damien Lawhorn, Vandana Rallabandi, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Distributed propulsion in aircraft has been shown to increase reliability and benefit aerodynamic performance. This paper discusses power electronic architectures and proposes control schemes suitable for distributed propulsion in hybrid and electric airplanes. Hybrid electric airplanes include permanent magnet synchronous generators driven by jet engines. The output of the generators is connected to the propulsion motors through back to back voltage source converters. Batteries, connected to the DC bus through buck-boost converters, are used to provide additional power to the propulsion motors during take off and climb. In the case of electric airplanes, the jet engine-permanent magnet generator system is …

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Multi-Physics Modeling For Electric And Hybrid Vehicles With In-Wheel Electric Motors, Vandana Rallabandi, Damien Lawhorn, Dan M. Ionel, Xiao Li Jun 2018

Multi-Physics Modeling For Electric And Hybrid Vehicles With In-Wheel Electric Motors, Vandana Rallabandi, Damien Lawhorn, Dan M. Ionel, Xiao Li

Power and Energy Institute of Kentucky Faculty Publications

This paper discusses multi-domain and multi-physics modeling of in-wheel electric vehicles using ANSYS Simplorer and ANSYS Maxwell. The study includes component level modeling of the vehicle, brakes, wheels, battery, traction motor, inverter, solar panels and boost converter. The traction motor used is an axial flux permanent magnet synchronous machine. In order to accommodate both the large time constants of the mechanical system and the high switching frequency power electronics, average models of the inverter and boost converter are considered. Simulation examples are provided for the University of Kentucky Gato Del Sol V car.

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A Comparative Study Of Constant Power Operation Techniques For Low Inductance Machines, Damien Lawhorn, Narges Taran, Vandana Rallabandi, Dan M. Ionel Jun 2018

A Comparative Study Of Constant Power Operation Techniques For Low Inductance Machines, Damien Lawhorn, Narges Taran, Vandana Rallabandi, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

In traditional electric machines, it is usually possible to achieve constant power high-speed operation by employing field weakening through the injection of a negative d-axis current component. However, in machines with low armature inductance, such as high power density permanent magnet synchronous machines, and more specifically, coreless machines, which are gaining increasing attention because of their high specific torque, the extended speed range obtained using this method is very narrow. This paper summarizes the performance characteristics of existing approaches for obtaining constant power operation and proposes two new techniques, specially applicable to coreless axial flux permanent magnet machine namely, current …

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