2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)最新文献

{"title":"Design and Development of a Dynamically, Scaled Distributed Electric Propulsion Aircraft Testbed","authors":"K. Pieper, Aaron T. Perry, Phillip J. Ansell, T. Bretl","doi":"10.2514/6.2018-4996","DOIUrl":"https://doi.org/10.2514/6.2018-4996","url":null,"abstract":"This paper details the motivation and design of a dynamically-scaled, distributed electric ducted fan testbed aircraft that was developed at the University of Illinois at Urbana-Champaign as part of a Phase I NASA STTR, in collaboration with Empirical Systems Aerospace. A 21 % subscale model of a Cirrus SR22T was developed and instrumented to perform system identification flight testing in support of dynamics model validation. A new wing configuration, featuring a series of electric ducted fans integrated into the wing upper trailing edge, was designed in order to provide a platform to investigate and quantify the effects of propulsion-airframe interactions and the effectiveness of propulsive-based control. Analysis and trade studies were performed to select an appropriate fan configuration that provided sufficient differential thrust to allow similar propulsion-based yaw control authority as the rudder control surface of the baseline vehicle. Wind tunnel experiments were performed on select propulsor combinations of motors, electronic speed controllers, and fans to validate performance specifications and capabilities. The new distributed electric propulsion wing was built and integrated into the baseline Cirrus and a simplified ground testing apparatus was constructed to validate the propulsion system before flight. The feasibility of scaling the designed distributed electric propulsion concept to a full-size equivalent general aviation aircraft was then explored.","PeriodicalId":276296,"journal":{"name":"2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115606597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Designing Fail-Safe Architectures for Aircraft Electrical Power Systems","authors":"J. Menu, M. Nicolai, M. Zeller","doi":"10.2514/6.2018-5032","DOIUrl":"https://doi.org/10.2514/6.2018-5032","url":null,"abstract":"More-electric, hybrid-electric, and all-electric aircraft have one important thing in common: they increasingly rely on electrical components and electrical power systems for fulfilling their principal functions. The increased dependency on electrical power has a drastic impact on the nature of the power generation and distribution system within the aircraft. New electrical components, often safety-critical, require completely rethinking of established electrical power system architectures. Manual (re)design, verification, and test of these complex systems becomes costly, cluttered, and often even infeasible. With a new methodology and software tool, we provide the ability to combine different aspects within the early design phases of electrical power systems. Based on a declarative component-based model, a designer can use the tool to automatically generate architectural variants. The component-based models seamlessly integrate with safety and reliability models in the form of component fault trees, which combine the traditional expressiveness of fault tree analysis for failure behavior with some notable advantages. Component fault trees enable the automatic ranking of the generated architectures in terms of safety and reliability attributes. By associating performance models with the original models, the tool also enables verifying complex functional requirements for the ranked architectures, again in a largely automated fashion. We demonstrate the developed methodology on two realistic use cases. In addition, we comment on the ability to apply the same methodology for the design of other systems (e.g., hydraulics, avionics). Indeed, the redesign of the electrical power system will often go hand in hand with rethinking other aircraft systems, because of their mutual interface(s).","PeriodicalId":276296,"journal":{"name":"2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128992409","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A High-Fidelity, Low-Order Propulsion Power Model for Fixed-Wing Electric Unmanned Aircraft","authors":"Or D. Dantsker, Mirco Theile, M. Caccamo","doi":"10.2514/6.2018-5009","DOIUrl":"https://doi.org/10.2514/6.2018-5009","url":null,"abstract":"In recent years, we have seen an uptrend in the popularity of UAVs driven by the desire to apply these aircraft to areas such as precision farming, infrastructure and environment monitoring, surveillance, surveying and mapping, search and rescue missions, weather forecasting, and more. These aircraft are more often being fully powered by electric power sources and a major technical hurdle is that of drastically reducing overall power consumption so they can be powered by solar arrays, and for long periods of time. To do so, the power requirement of an aircraft and the conversion efficiency of its propulsion system, from electrical energy to thrust, must be parametrized so that it can be improved. This paper describes a high-fidelity, low-order power model for electric, fixed-wing unmanned aircraft using flight path information. The motivation behind this work is the development of computationally-intensive, long-endurance solar-powered unmanned aircraft, the UIUC Solar Flyer, which will have continuous daylight ability to acquire and process high resolution visible and infrared imagery. Therefore, having an accurate power model will aid in providing the ability to predict power usage for future mission flight segments, which will be vital for energy-conscious path planning. Compared to works in the existing literature, the model presented follows a holistic approach for fixed-wing electric UAV power modeling that encompasses both aircraft aerodynamics and propulsion models under realistic assumptions. The model developed is able to very accurately estimate the power consumption of an electric UAV based on flight path state, without needing precise aerodynamic measurements, therefore doing so with minimal computation power. The propulsion power model was evaluated by means of flight testing as well as simulation and showed errors ranging from negligible to approximately 5%.","PeriodicalId":276296,"journal":{"name":"2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126694495","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fundamentals of Parallel Hybrid Turbofan Mission Analysis with Application to the Electrically Variable Engine","authors":"Jonathan C. Gladin, David Trawick, D. Mavris, M. Armstrong, D. Bevis, Kyle Klein","doi":"10.2514/6.2018-5024","DOIUrl":"https://doi.org/10.2514/6.2018-5024","url":null,"abstract":"This paper describes a basic analysis for mission performance of parallel hybrid turbofan systems. A series of equations is derived to illustrate the concept of parallel hybrid performance showing that there is an optimum range for a given battery size that corresponds to the exact usage of the battery capacity stored on the aircraft. The fundamental concepts were then demonstrated on a more detailed problem using a performance model of the Electrically Variable Engine developed by Rolls-Royce on a high aspect ratio vehicle. Trends from this study again demonstrate the concepts derived in the preliminary theoretical analysis. Finally, a standard method for presenting hybrid data is proposed called the “money chart” which is a means for showing all of the required performance parameters of a parallel hybrid system to compute other metrics of interest as desired.","PeriodicalId":276296,"journal":{"name":"2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128523451","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NASA Electric Aircraft Testbed (NEAT) Single-Aisle Transport Air Vehicle Hybrid Electric Tail-Cone Thruster Powertrain Configuration and Test Results","authors":"R. Dyson","doi":"10.2514/6.2018-5004","DOIUrl":"https://doi.org/10.2514/6.2018-5004","url":null,"abstract":"A key technical challenge is to establish a viable concept for a MW -class hybrid gas-electric propulsion system for a commercial transport aircraft. This includes developing aircraft propulsion system conceptual designs, integrating sub-systems, high efficiency/power density electric machines, flight-weight power system and electronics, and enabling materials in high voltage insulation, high frequency soft magnetics, and conductors. The primary benefit of this research is to diversify the current turbofan propulsion options to include hybrid electric propulsion elements that reduce energy usage, emissions, and noise. A reconfigurable powertrain testbed at NASA Glenn Research Center is described including test results from the initial 500 kW powertrain configuration.","PeriodicalId":276296,"journal":{"name":"2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120945151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Lightweight, Durable, and Multifunctional Electrical Insulation Material Systems for High Voltage Applications","authors":"Euy-Sik Eugene Shin, D. Scheiman, M. Lizcano","doi":"10.2514/6.2018-5013","DOIUrl":"https://doi.org/10.2514/6.2018-5013","url":null,"abstract":"Newly developed multilayer structures of well-known polymer insulation materials significantly improved dielectric breakdown voltage, VB, or dielectric strength, K, if well-bonded, when compared to those of single material insulations or the commercial SOA systems, such as Teflon-Kapton-Teflon (TKT), at the same overall thickness. To date, the greatest improvement of the new structures from a few candidate materials, including various types of Kapton PIs and PFA or PET as bond layer (BL), was about 61% higher than that of the Kapton PI alone films, 40.1 vs. 24.9 kV, which was translated to 86.3% decrease in insulation thickness, thus significant volume and weight reduction of the final system. However, it was of interest to note that most improvements of the multilayer structures occurred at thicker overall thicknesses, above ~ 0.15 mm. Extensive analyses also showed that K of the multilayer structures increased with (i) decreasing individual layer thickness regardless of material type, (ii) increasing total accumulated thickness of PI or overall PI/BL ratio, and (iii) increasing number of interface or total number of layers, but only above the aforementioned overall thickness limit. Increases in VB or K of the multilayer structures were directly correlated with damage evolution and failure mode. With further material-design-process optimizations of the multilayer structures, it was expected to achieve other multifunctionalities, such as high partial discharge (PD) resistance, improved durability, EMI shielding, and high thermal dissipation in addition to high dielectric strength. These new structures can be used in various high voltage and high temperature applications, such as future hybrid or all electric aircraft wiring and power transmission as well as many other non-aerospace high power cables, electronic parts and components, printed circuit board, and so forth. The multilayer insulation system can be easily processed and manufactured with various conductor types via calendaring, compression-molding, stamping, laminating, vacuum-bagging and autoclaving, or 3D printing, even for complex 3-D components. Based on their unique structural configurations and potential capabilities, the new insulation system was identified as micro-multilayer multifunctional electrical insulation (MMEI). Patent application of the MMEI concept and current design configurations was filed for a 1-year provisional application (OAI-58834, Serial No.: 62/659,234), pending conversion to a U.S. utility application. This paper presents details of the MMEI structures, their dielectric performance analyses, potential mechanisms, and commercial scaleup feasibility assessment.","PeriodicalId":276296,"journal":{"name":"2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)","volume":"281 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122941993","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of a Fuel-Cell/Battery /Supercapacitor Hybrid Propulsion System for a UAV Using a Hardware-in-the-Loop Flight Simulator","authors":"Andrew Gong, R. MacNeill, D. Verstraete, J. Palmer","doi":"10.2514/6.2018-5017","DOIUrl":"https://doi.org/10.2514/6.2018-5017","url":null,"abstract":"Fuel-cell based hybrid propulsion systems are being considered as a means to increase the endurance and range of small electric powered unmanned aerial vehicles. However fuel cell durability is limited by the rapid load changes requested by the autopilot. In a fuel-cell/battery /supercapacitor triple hybrid the battery provides boost power whilst the supercapacitor increases fuel cell life through load levelling. This paper presents the analysis of a fuel-cell/battery /supercapacitor hybrid propulsion system using a high fidelity hardware-in-the-loop simulator. The hardware-in-the-loop simulator allows accurate application of the expected dynamic electrical loads experienced in flight on the hardware components without the risks associated with flight testing. The triple hybrid system demonstrates load smoothing by the supercapacitor to the fuel cell under simulated operating conditions, with this buffering increasing fourfold under gusty flight conditions.","PeriodicalId":276296,"journal":{"name":"2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124746664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A Review of Distributed Electric Propulsion Concepts for Air Vehicle Technology","authors":"H. D. Kim, Aaron T. Perry, Phillip J. Ansell","doi":"10.2514/6.2018-4998","DOIUrl":"https://doi.org/10.2514/6.2018-4998","url":null,"abstract":"The emergence of distributed electric propulsion (DEP) concepts for aircraft systems has enabled new capabilities in the overall efficiency, capabilities, and robustness of future air vehicles. Distributed electric propulsion systems feature the novel approach of utilizing electrically-driven propulsors which are only connected electrically to energy sources or power-generating devices. As a result, propulsors can be placed, sized, and operated with greater flexibility to leverage the synergistic benefits of aero-propulsive coupling and provide improved performance over more traditional designs. A number of conventional aircraft concepts that utilize distributed electric propulsion have been developed, along with various short and vertical takeoff and landing platforms. Careful integration of electrically-driven propulsors for boundary-layer ingestion can allow for improved propulsive efficiency and wake-filling benefits. The placement and configuration of propulsors can also be used to mitigate the trailing vortex system of a lifting surface or leverage increases in dynamic pressure across blown surfaces for increased lift performance. Additionally, the thrust stream of distributed electric propulsors can be utilized to enable new capabilities in vehicle control, including reducing requirements for traditional control surfaces and increasing tolerance of the vehicle control system to engine-out or propulsor-out scenarios. If one or more turboelectric generators and multiple electric fans are used, the increased effective bypass ratio of the whole propulsion system can also enable lower community noise during takeoff and landing segments of flight and higher propulsive efficiency at all conditions. Furthermore, the small propulsors of a DEP system can be installed to leverage an acoustic shielding effect by the airframe, which can further reduce noise signatures. The rapid growth in flight-weight electrical systems and power architectures has provided new enabling technologies for future DEP concepts, which provide flexible operational capabilities far beyond those of current systems. While a number of integration challenges exist, DEP is a disruptive concept that can lead to unprecedented improvements in future aircraft designs.","PeriodicalId":276296,"journal":{"name":"2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126244350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Creating a Multifunctional Composite Stator Slot Material System to Enable High Power Density Electric Machines for Electrified Aircraft Applications","authors":"A. Woodworth, R. Jansen, K. Duffy, Paria Nazhipour Author, Euv-Sik Shin","doi":"10.2514/6.2018-5012","DOIUrl":"https://doi.org/10.2514/6.2018-5012","url":null,"abstract":"Increasing the power density and efficiency of electric machines (motors and generators) is integral to bringing Electrified Aircraft (EA) to commercial realization. However, power density and efficiency are not qualities that can be developed independently. At the heart of any electric machine are the conductors (usually copper) that carry current and generate magnetic fields. Increased power density means increased current density and increased joule heating in a smaller volume. To increase efficiency at the wire level means minimizing electrical resistance and hence power lost to joule heating. There are fundamental challenges with concomitantly increasing both power density and efficiency since the copper resistivity is very temperature sensitive at common electric machine operating conditions. Simple calculations of the linear increase in resistivity of copper as a function of temperature, reveals that a one degree Celsius increase in temperature results in a 0.39% decrease in efficiency. Conversely, a 20 degree Celsius decrease in copper temperature produces a 7.8% increase in efficiency. Therefore, improved thermal management concepts for electric machine building blocks such as stator winding are a priority for improving efficiency and power density. This paper proposing changing the view of component materials in the stator slots from individual components with singular functionality to a composite system where the components take on a multifunctional roles. In the composite framework, achievable material development goals are defined that together have maximum system impact on the thermal environment inside of high power density electric machines for aerospace applications.","PeriodicalId":276296,"journal":{"name":"2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125944232","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Real-Time Simulation of a More Electric Aircraft Power Generation and Distribution System","authors":"M. Rivard, C. Fallaha, J. Paquin","doi":"10.2514/6.2018-5016","DOIUrl":"https://doi.org/10.2514/6.2018-5016","url":null,"abstract":"More Electric Aircraft (MEA) technology is leading aircraft manufacturers to replace traditional hydraulic and pneumatic systems by electrical components, resulting in weight and maintenance cost reduction, and in the increase of Mean Time Between Failures (MTBF). This has for effect of increasing the complexity of the Electrical Power Generation and Distribution System (EPGDS) of the aircraft and degrading its power quality. As a result, testing and validation must be performed early in the design stages, which has traditionally been done via the use of physical testbeds which involve significant amount of hardware. However, because of the electrical nature of MEA, virtual testbeds are now increasingly used, which offer greater flexibility and are less costly than conventional testbeds. As such, OPAL-RT is developing real-time simulators that integrate MEA systems models into a real-time co-simulation platform. This paper provides simulation results that showcase OPAL-RT's real-time simulation capabilities in the context of EPGDS simulation, applied to a generic example inspired from public domain publication regarding the Boeing 787 EPGDS.","PeriodicalId":276296,"journal":{"name":"2018 AIAA/IEEE Electric Aircraft Technologies Symposium (EATS)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-07-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129475062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}