ARPA-E ELECTRIC MOTORS FOR AVIATION WORKSHOP Michael Ohadi, Program - PowerPoint PPT Presentation

ARPA-E ELECTRIC MOTORS FOR AVIATION WORKSHOP Michael Ohadi, Program Director Michael Ohadi Grigorii Soloveichik David Tew Isik Kizilyalli Chris Atkinson Gregory Thiel Vivien Lecoustre Ziaur Rahman Dipankar Sahoo

Aviation: Difficult-to-eliminate CO 2 emissions 1

Aviation: Traffic to triple by 2050 Annual airline passengers Aviation GHG emissions • CO 2 emissions from international aviation, as well as global fleet, will triple at the horizon by 2050 • Anticipated that aviation industry will miss ICAO’s 2020 and 2030 fuel -efficiency goals for new aircraft by more than a decade (due to focus on re-motorization instead of clean-sheet design) https://data.worldbank.org/indicator/is.air.psgr 2

Aviation: Public perception shifts negatively toward flying * *Swedish for “flight shame” 2,000 responders from US and Germany Norway banned regional fossil fuel flight by 2040 3

Aviation: Electric aviation enables new, efficient aircraft design ‣ Electric propulsion offers fundamentally different characteristics with several notable benefits: – > 2x efficiency of SOA engines (especially for smaller engines), simplicity – Increased safety through redundancy, extremely quiet, no power lapse with altitude or hot day ‣ Electric propulsion scale-free nature enables distributed propulsion ‣ Distributed propulsion: distributing the airflows and forces about the aircraft improves the aerodynamics, propulsive efficiency , structural efficiency, etc. 4

Aviation: Some concept designs of electric aviation A.M.Stoll , et al., “ Drag Reduction Through Distributed Electric Propulsion ”, 2014 K. Moore, A. Ning, “Distributed Electric Propulsion Effects on Traditional Aircraft Through Multidisciplinary Optimization” 2018 Source: Mark Moore, Distributed Electric Propulsion (DEP) Aircraft, 2012, NASA Langley Research Center 5

Aviation: Civil aviation segments, where should we focus? Boeing B737-MAX 8 Beechcraft 1900 Range: 6,570 km Range: 1,900 km MTOW: 82,191 kg MTOW: 7.766 kg Take-off thrust: 130.4 kN Take-off thrust: 9.8 kN Single-aisle (narrow-body): 100 – 200 passengers Commuter: < 20 passengers MRJ 70 Boeing 777 Range: 1,880 km Range: 15,840 km MTOW: 40,200 kg MTOW: 300,000 kg Take-off thrust: 67 kN Take-off thrust: 440 kN Main focus on narrow-body aircraft Regional: 30-100 passengers Example: Boeing 737 6

Aviation: Drivers for electric aviation Asian demand will be the largest at 6,710 planes, followed by Europe (5,380), North America Most ordered narrow-body aircraft (5,180), and Latin America (1,800) 7

Aviation: Addressing ARPA-E mission areas Global civil aviation fuel consumption ‣ Reduced emissions  ‣ Increased efficiency   ‣ Reduce imports ‣ Technological competiveness – Enhances domestic aerospace industry – Ensures export of US technology and enables regional mobility around the globe Any savings on fuel consumption can have massive impact on U.S. energy and emissions 7

Aviation: System block diagram Shaft Electricity Thrust Out Fuel In Propulsor Energy Storage and Power Conversion Conversion (ESC) System (PCS) Overall Propulsion System 9

Aviation: Electric aviation needs (stakeholder input) • Energy storage to provide target flying range and payload (show stopper) • Light, efficient and high power density electric motors (enabler) • Power electronics to convert, switch and condition the needed power at high voltage (enabler) • Safe and light high voltage distribution to deliver high power (enabler) 10

SCENARIO STUDIES – B737-MAX8 ELECTRIFICATION 11

Aviation: Narrow-body aircraft & mission specifications For this analysis, aircraft is assumed to take-off at its maximum take-off weight (MTOW); with its maximum payload (Pl max = 20,882 kg); at given cruise speed 90,000 MTOW = 82,191 kg 80,000 Sub-system weight [kg] Fuel Weight 16,239 70,000 [kg] 60,000 Max Payload Boeing B737-MAX 8 20,882 50,000 Weight [kg] Single-aisle (narrow body): 100 – 200 passengers 40,000 Aircraft Cruise speed: 839 km/h Structure 30,000 MTOW: 82,191 kg Weight [kg] 39,510 Cruise thrust power: 8.7 MW (calculated) 20,000 Propulsion Range: 6,570 km System 10,000 Weight [kg] Propulsive System: 2 x CFM LEAP 1B 5,560 Take-off thrust: 2 x 130.4 kN 0 B737-Max8 12

Aviation: System block diagram Shaft Electricity Thrust Out Fuel In Propulsor Energy Storage and Power Conversion Conversion (ESC) System (PCS) Overall Propulsion System 13

Aviation: Overall propulsion system specific power Thrust Out Electricity Shaft 𝜌 𝑄𝐷𝑇 = 𝑄 𝑡ℎ𝑏𝑔𝑢 𝜌 𝑄𝑠𝑝𝑞 = 𝑄 𝑈ℎ𝑠𝑣𝑡𝑢 Fuel In 𝜌 𝐹𝑇𝐷 = 𝑄 𝑓𝑚𝑓𝑑 𝑁 𝑄𝐷𝑇 𝑁 𝑄𝑠𝑝𝑞 𝑁 𝐹𝑇𝐷 𝑄 𝑡ℎ𝑏𝑔𝑢 𝑄 𝑓𝑚𝑓𝑑 𝑄 𝑡ℎ𝑏𝑔𝑢 𝑄 𝑈ℎ𝑠𝑣𝑡𝑢 𝑄 𝑓𝑚𝑓𝑑 𝜃 𝑄𝐷𝑇 = 𝑄 𝑈ℎ𝑠𝑣𝑡𝑢 𝜃 𝑄𝑠𝑝𝑞 = 𝜃 𝐹𝑇𝐷 = 𝑄 𝑓𝑚𝑓𝑑 𝑄 𝑡ℎ𝑏𝑔𝑢 𝑄 𝑔𝑣𝑓𝑚𝑗𝑜 Power Conversion Energy Storage and Propulsor System (PCS) Conversion (ESC) Overall Propulsion System 𝜽 𝒑𝒘𝒇𝒔𝒃𝒎𝒎 𝝆 𝒑𝒘𝒇𝒔𝒃𝒎𝒎 = 𝜽𝒑𝒘𝒇𝒔𝒃𝒎𝒎 𝜽𝑸𝑫𝑻𝜽𝑭𝑻𝑫 + 𝜽 𝑭𝑻𝑫 𝝆𝑸𝒔𝒑𝒒 + 𝝆𝑸𝑫𝑻 𝝆𝑭𝑻𝑫 14

Aviation: System block diagram Shaft Thermal Management Energy Fuel In System(s) conversion CNLF tank Thrust Out engine Electric Power Electronics Motor Battery (TO only) Power Delivery Power Conditioning Electricity Unit (PDU) Unit (PCU) Propulsor Energy Storage and Power Conversion Conversion (ESC) System (PCS) Overall Propulsion System 15

Aviation: Component-level specific power targets 𝜃 𝑄𝐷𝑇 𝜃 𝐹𝑇𝐷 𝜌 𝑄𝐷𝑇 = 100% 1 𝜌 𝑄𝑠𝑝𝑞 − 𝜃 𝐹𝑇𝐷 1 80% 90% 𝜃 𝑝𝑤𝑓𝑠𝑏𝑚𝑚 𝜌 𝑝𝑤𝑓𝑠𝑏𝑚𝑚 − 𝜌 𝐹𝑇𝐷 η overall = 60% π overall = 1,250 W/kg (100% range) π overall = 1,045 W/kg (90% range) π overall = 895 W/kg (80% range) INPUTS η Prop = 90%, π prop = 5,000 W/kg η ESC = 70% η PCS = 95% Range = 0.9x For π ESC ≥ 2,000 W/kg Need π PCS ≥ 6,400 W/kg 16

Aviation: Electric Motors – Still a long way to go… State of the Art (Overview) Industry feedback: ARPA-E motor (includes TMS) • Specific Power, good metrics >(TBD) kW/kg,  > (TBD) % for powertrain comparisons. Example: Aviation & EV Continuous Specific powertrain Power (kW/kg) • Cruise Efficiency, important Siemens motor metrics for aviation and wind 5 kW/kg,  = 95% generators Remy motor 2 kW/kg,  = 92% Marathon motor • Specific Torque, another 0.2 kW/kg,  = 85% metrics to compare motors and thermal capabilities. • Volumetric density, also a good metrics for aviation Electric Aviation application for drag and noise Industrial EV Drive Aviation (Single Aisle) constraints 17

Aviation: Importance of thermal management of electric motor Reduced power & torque at Increasing losses with Reduced efficiency with elevated temperatures increasing temperature reduced weight Passive two- Pumped two- Air natural Air forced Liquid phase cooling phase cooling convection convection cooling (heat pipe) (likely in the future) Processors & power electronics cooling over time Rotor-embedded Housing fins heat pipe (Tesla) Shaft-driven fan Ethylene glycol (Nissan) 18

Aviation: Integrated multiphysics co-design (electric/electromagnetic/thermal/mechanical) Identification of topologies/architectures, materials, and manufacturing Innovative Manufacturing Innovative methodologies, embedded cooling with Designs supercritical fluids to achieve the targeted metrics: Innovative Materials  Utilizes low resistance/near source cooling  High power density  High efficiency  Compact Co-design of electromagnetics,  Reliable inactive materials, thermal, and  Meets roadmap to commercialization power conditioning is a must 19

Aviation: Light weight motors, what’s possible? Tesla S60 induction motor Co-design process: use of advanced inactive materials BMW i3 and electromagnetic optimization State of art Advances in insulation Embedded cooling Additive/advanced materials and use of highly manufacturing of motor potent fluids winding and other (supercritical etc.) components • “Challenges in 3D printing of high conductivity copper” – IPACK2017-74306 • “Cooling of windings in electric machines via 3D printed heat exchanger” – ECCE 2018 20 • “Advanced cooling concepts for ultra -high- speed machines” – ECCE Asia 2015

BREAKOUT SESSION 21

Breakout sessions – Morning and Afternoon Jackson, Lee, and Jefferson Rooms – Lobby Level 22