Engineering Commons^™

Cost Minimization Of Battery-Supercapacitor Hybrid Energy Storage For Hourly Dispatching Wind-Solar Hybrid Power System, Pranoy Roy, Jiangbiao He, Yuan Liao

Electrical and Computer Engineering Faculty Publications

This study demonstrates a dispatching scheme of wind-solar hybrid power system (WSHPS) for a one-hour dispatching period for an entire day utilizing battery and supercapacitor hybrid energy storage subsystem (HESS). A frequency management approach is deployed to extend the longevity of the batteries through extensively utilizing the high energy density property of batteries and the high power density property of supercapacitors in the HESS framework. A low-pass filter (LPF) is employed to decouple the power between a battery and a supercapacitor (SC). The cost optimization of the HESS is computed based on the time constant of the LPF through extensive …

Design Optimization And Comparison Of Direct-Drive Outer-Rotor Srms Based On Fast Current Profile Estimation And Transient Fea, Vandana Rallabandi, Peng Han, Jie Wu, Aaron M. Cramer, Dan M. Ionel, Ping Zhou

Power and Energy Institute of Kentucky Faculty Publications

Outer-rotor switched reluctance machines (SRMs) have drawn much attention as promising candidates for in-wheel direct-drive motors of future electric vehicles. This article presents a systematic performance comparison of three outer-rotor SRM topologies for in-wheel traction applications in terms of the specific torque, electromagnetic efficiency, torque ripple, radial force, and mechanical aspects. A generalized design optimization framework for SRMs is proposed to enable the fast evaluation of large numbers of designs generated from the differential evolution by incorporating an analytical current profile estimation into the transient finite element analysis. The relationship between the saliency ratio and converter volt-ampere rating is also …

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 …

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. …

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 …

Optimal And Secure Electricity Market Framework For Market Operation Of Multi-Microgrid Systems, Mohammad Mahmoudian Esfahani

FIU Electronic Theses and Dissertations

Traditional power systems were typically based on bulk energy services by large utility companies. However, microgrids and distributed generations have changed the structure of modern power systems as well as electricity markets. Therefore, restructured electricity markets are needed to address energy transactions in modern power systems.

In this dissertation, we developed a hierarchical and decentralized electricity market framework for multi-microgrid systems, which clears energy transactions through three market levels; Day-Ahead-Market (DAM), Hour-Ahead-Market (HAM) and Real-Time-Market (RTM). In this market, energy trades are possible between all participants within the microgrids as well as inter-microgrids transactions. In this approach, we developed a …

A Network Graph Technique For The Design Of Electric Aircraft Power Systems, Damien Lawhorn, Vandana Rallabandi, Dan M. Ionel

Power and Energy Institute of Kentucky Faculty Publications

Today the electrification of flight is more popular than ever, creating a wide array of concept aircraft and associated power system topologies. In order to gain insights into benefits of these varying architectures, this paper introduces the development of a framework for electric aircraft power system (EAPS) optimization. The proposed framework accepts inputs from a designer in the form of component parameters and desired flight mission characteristics. A collective graph representing many architectures is formed, from which, subgraphs or power system topologies meeting the flight requirements are extracted and analyzed. An optimum topology meeting the flight requirements with minimum mass, …

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 …