1、/2727May 18,2024Johann W.Kolar et al.Swiss Federal Institute of Technology(ETH)ZurichPower Electronic Systems Laboratorywww.pes.ee.ethz.che-VTOL Aircraft The Future of Urban Air Mobility/2727May 18,2024Johann W.Kolar,David Menzi,Luc Imperiali,Elias Brgisser,Jonas E.HuberSwiss Federal Institute of Te

2、chnology(ETH)ZurichPower Electronic Systems Laboratorywww.pes.ee.ethz.che-VTOL Aircraft The Future of Urban Air Mobility/2727Outline Once Upon a Time eVTOL Aircraft Concepts Energy/Power Sources El.Motor Technologies On-Board Power Electronics Ultra-Fast Battery Charging Sustainability Acknowledgmen

3、tMartin Ulmer/2727Once Upon a Time “Magic Carpets”Featured in the“1001 Nights”and Modern Literature Quietly and Swiftly/Instantaneously Carrying their Users to Desired Destinations Handbook on How to Operate a Magic Carpet for“Young or Vertically Challenged People”1 1/2727Todays Motivation Use 3D-Ai

4、rspace to Alleviate Transportation Congestion on the Ground “Flying Cars”2015 Typ.San Francisco Resident Spent 230h/Year Commuting btw.Work&Home 500000 Hours of Productivity Lost/Single Day Source:http:/ 2 2/2727Todays Motivation Use 3D-Airspace to Alleviate Transportation Congestion on the Ground “

5、Flying Cars”2015 Typ.San Francisco Resident Spent 230h/Year Commuting btw.Work&Home 500000 Hours of Productivity Lost/Single DaySource:https:/ 3/2727Operation CharacteristiceVTOL Aircraft Types Urban Air Mobility/27274 4Source:2020“Pop.Up Next”Modular All-Electric Drone 4x2 Rotors|People-Pod|EV Chas

6、sis(Airbus&Audi until 2019)Urban Air Mobility(UAM)“On-Demand”UAM City Taxi/Intra-City/Inter-City Transport as Main Use Cases Distributed Electric Propulsion Quiet/Efficient/Clean/Safe Vertical Take-Off&Landing(VTOL)Aircraft “Vertiports”/No Runways/2727Types of eVTOL Aircraft Multicopter Wingless/Dis

7、tributes Thrust to Fly/Short Distances Lift-Thrust Wings/Independent Lift&Thrust Units/Low Complexity Vectored Thrust Wings/Propulsion Units Rotate to Provide Lift&Thrust All-Electric Energy Supply Battery or Hybrid Battery/Fuel-Cell Combination 5 5eVTOL vs.Helicopter 15dB Lower Noise Maintenance$11

8、0,-/Hour(25%)OPEX$3570,-/Hour(20%)Zero Emissions Future Full Automation No Pilot Catastr.Failure 1/109Hours (10-4)Small Take-Off/Lndg FootprintSource: Aircraft Concepts(1)Volocopter(Germany)VoloCity 18 El.Rotors|Vert.Lift&Hover Flight|900kg Max.Take-Off Weight 2 Passengers|110km/h Cruise Speed|36km

9、Range EASA Certification Process On-Going(Target:2024)Freight-Carrying VoloDrone Announced6 6/2727eVTOL Aircraft Concepts(2)Metro Skyways(former Urban Aeronautics Ltd.,Israel)CityHawk 2 Slow-Turing Ducted Fans|Vert.Lift&Horiz.Flight|2000kg Max.Take-Off Weight 4 Passengers|280km/h Cruise Speed|280km

10、Range Initially Powered with Fossil Fuel|Transition to Fuel-Cell Power Supply Small Operating Space|Intended for Urban Areas/In Service 2028-20307 7/2727eVTOL Aircraft Concepts(3)Joby Aviation(USA)Joby S4 2.0 6 Tilt-Propellers|Vert.Lift&Horiz.Flight|2200kg Max.Take-Off Weight 4 Passengers|320km/h Cr

11、uise Speed|240km Range Uber Elevate Acquired by Joby Aviation in 2020/Commercial Operation Planned for 2024 Battery Powered|Range Extension w/Hybrid Fuel-Cell/Battery Architecture Announced8 8/2727eVTOL Aircraft Concepts(4)Lilium(Germany)Lilium Jet 36 Ducted El.Fans|Vectored Thrust Vert.Lift&Horiz.F

12、light|3100kg Max.Take-Off Weight 6 Passengers|280km/h Cruise Speed|250km Range Partnership w/Lufthansa Aviation/Commercial Operation Planned for 2025 Extreme Requirements on Battery Technology/320kW Total Propulsion Power(Horiz.Flight)9 9/2727eVTOL Aircraft Concepts(5)Skydrive Inc.(Japan)SkyDrive SD

13、-03 4x2 El.Rotors|Vert.Lift&Hover Flight|400kg Max.Take-Off Weight 1 Passenger|50km/h Cruise Speed|2000)Battery Pack Wh/kg typ.8090%of Cell Energy/Power Density Affects Payload&Range Far Higher Requirements Compared to EV H2Fuel-Cells typ.5001500Wh/kg|400600W/kg -Dependent on Payload&Range 13131C Di

14、s-/Charge in 1h5C 12minSoA State of the Art/2727Electric Power SystemBuck-Boost DC/DC ConversionUltra-Light Weight Power Electronics/27271414Fuel-Cell/Battery Power Electronics Interface Overlapping Input/Output Voltage Ranges Buck-Boost DC/DC Converter Design Example Modular 150kW System 15kW Modul

15、e|UFC=480800V|UBatt=450720V Multi-Objective Comparative Analysis 2-Level(ZVS)|Multi-Level|Partial Power Processing Topology /27271515Fuel-Cell/Battery Power Electronics Interface Overlapping Input/Output Voltage Ranges Buck-Boost DC/DC Converter Module 15kW|UFC=480800V|UBatt=450720V|TC=80C,Tj 150C M

16、ulti-Objective Comp.Analysis 2-Level(SiC)fsw=275kHz|3-Level(GaN)fsw=400kHz(fsw,eff=800kHz)Mission Efficiency 50%Climbing/50%Cruising/No Fuel-Cell Power During Descent DC/DC Conv.Off System Considerations Battery&Fuel-Cell Weight vs.Converter Weight Adv.of High Eff.ConverterRel.Share of Inductor/2727

17、m=175g=86kW/kg=108kW/dm3=98.1%(Mission)m=346g=44kW/kg =82kW/dm3=98.8%(Mission)2x1616Comparative Evaluation 2L vs.3L Converter Exp.System Power Density Higher than Calculated due to 3D-Printed Cold Plate&Sandwich Structure Ultra-High Power Density Design Target of 20kW/kg Achievable w/Low-Complexity

18、2-Level Approach3-Level Converter 2-Level Converter Overlapping Input/Output Voltage Ranges Buck-Boost DC/DC Converter Module 15kW|UFC=480800V|UBatt=450720V/27271717 3D-Printed Alumina H2O-Cooler/600V GaN Power Transistors3-Level Converter Hardware Demonstrator Overlapping Input/Output Voltage Range

19、s Buck-Boost DC/DC Converter Module 15kW|UFC=480800V|UBatt=450720V/272718183-Level Converter Experimental Results=86kW/kg MissionMission=98.1%Overlapping Input/Output Voltage Ranges Buck-Boost DC/DC Converter Module 15kW|UFC=480800V|UBatt=450720V Rated Power/2727eVTOL Aircraft Electric Motor Technol

20、ogy Best-in-Class 30Nm/kg|15kW/kg Motor Scaling Acc.to Torque M(!)|P=M.High Speed/Power Density&Gearbox OR Direct-Drive Adv./Low-Weight Radial-or Axial-Flux Motors incl.Concepts w/Integr.Magnetic Gear 20kW/kg Target CityAirbus Demonstrator(2020)8x 100kW Direct-Drive Rolls-Royce(SIEMENS)Adv.Motor Tec

21、hnology 4x2 Ducted Co-Axial Propellers Low Noise|400kg Trust/Duct|250kg Payload|120km/h for 15min1919Source:/2727Solid-State TransformersHigh-Power Battery Charging/2727Ultra-Fast Battery Charging 20%100%Charging of typ.200400kWh Battery in 1520min Mandatory for High eVTOL Utilization MegaWatt Charg

22、ing System(MCS)For Heavy-Duty Trucks|Buses Basis for eVTOL Aircraft AIR7357 Std ChargePoint 2-MW Charge Connector(max.1000V/4 x 500A)incl.Liquid Cooling&High-Speed Data Transfer Source:2020/2727 Power Density 0.09kW/dm3(System)|0.18kW/dm3(SST/Cells incl.Isol.)-40%Footprint/-70%Weight vs.LFT-Based So

23、lution/83%Lower Transf.Volume 3-6.6kV Input/350kW SST-Based EV Charger(1)3x7=21 Cells|5kHz 1.7kV Si-IGBT AC/DC Stage|50kHz 1.7kV SiC 1050V/400V DC/DC Converter Matrix Switch Output for 21x 17kW 1x 350kW Charging Port Config.&Cascaded Cell Balancing Forced Air Cooling Source:2121 2000 x 1000 x 2000 m

24、m /2727Source:22223-6.6kV Input/350kW SST-Based EV Charger(2)Power Density 0.09kW/dm3(System)|0.18kW/dm3(SST/Cells incl.Isol.)-40%Footprint/-70%Weight vs.LFT-Based Solution/83%Lower Transf.Volume 3x7=21 Cells|5kHz 1.7kV Si-IGBT AC/DC Stage|50kHz 1.7kV SiC 1050V/400V DC/DC Converter Matrix Switch Out

25、put for 21x 17kW 1x 350kW Charging Port Config.&Cascaded Cell Balancing Forced Air Cooling/2727 Exchange of Drained Battery in Only 5min(!)Re-Charging of Batteries in Controlled Environment Low Energy$Time Periods Disadvantage of Standardized Single-Pack Battery Design&Battery Accessibility Required

26、 2323Alternative Battery SwappingSource:https:/ Growth PerspectivesCarbon Footprint vs.ICE&EVEconomic Perspectives&Sustainability/27272424 160000 Passenger Drones Expected by 2050 Add.Market for Services/Repairs etc.USD 900 Million Investments in 1stHalf of 2020 20 x Level of 2016(Full Year)Industry

27、 Expected to be Ready for Take-Off in 2025 25%CAGR Predicted By 2050 Estimated Revenues of USD 90 Billion/Year(1 Billion in 2030)Urban Air Mobility(UAM)Market ForecastSource:2020/2727Certification&Future Airspace Interaction Concept2525 US Federal Aviation Admin.(FAA)/EU Aviation Safety Agency(EASA)

28、Regulations&Certifications Buildings/Towers&Noise-Sensitive Areas Def.of Low-Altitude UAM Corridors&Holding Areas Targets EASA Certification for“VoloCity”in 2024 Source:Y.Lee et al.|applied sciences/27272626 Study of (2015)on Cost/Time of Commuting btw Cities eVTOL Aircraft vs.Cars On-Demand Urban A

29、ir Transportation UberCopter as 1stStep Intercity Flights Rel.Short Offset Transfer Time Vertiports|Time Saving&High eVTOL Utilization Lilium 6 Passengers|250km Range|280km/h Cruise Speed|20-25 Flights per DayUAM Comparative Evaluation(1)4 pax/27272727 eVTOL Aircraft Provide 2x 6x Faster Means of Po

30、int-to-Point Mobility Up to 300mi of Range with up to 7 Passengers Using Latest Battery Technology EV and ICEV 220 Wh/Passenger-mi and 1,000 Wh/Passenger-mi eVTOL Aircraft 130 Wh/Passenger-mi 1,200 Wh/Passenger-mi Dep.on Design&OccupancyUAM Comparative Evaluation(2)/2727Thank you!Source:Paul Bunchhttps:/