Results for “Electrified propulsion” — Page 14

NASA NTRSDate not supplied

SUbsonic Single Aft eNgine (SUSAN) Power/Propulsion System Hardware-in-the-Loop Test Results

Electrified Aircraft Propulsion (EAP) technology offers a promising path forward for reducing greenhouse gas emissions and other negative environmental effects from the commercial aviation sector. EAP systems can reduce fuel burn and improve performance over state-of the-art designs, however the increased complexity and highly coupled nature of these systems present challenges that require new control approaches. The SUbsonic Single Aft eNgine (SUSAN) Electrofan is a concept aircraft developed by NASA as a reference design for a commercial transport aircraft with a highly integrated hybrid-electric powertrain. This paper summarizes the results of a Hardware-in-the-Loop (HIL) test of a control architecture developed for the SUSAN power/propulsion system (PPS). The test was performed in the Hybrid Propulsion Emulation Rig (HyPER) facility at the NASA Glenn Research Center (GRC) and involved a real-time reference model of the SUSAN PPS and control system running with a sub-scale electro-mechanical system replacing one of the PPS subsystems. A side-by-side comparison of the simulated and real systems in the HIL test results shows that the control architecture functions well in both the simulation and the real-time HIL environment. In both cases the controller is able to simultaneously deliver the required thrust response and balance power levels between the electrical and turbomachinery subsystems.

EAP↗

NASA NTRSDate not supplied

Design Implications of Rotordynamics and Mass Balancing on a 1.4 MW Partially Superconducting Machine

To ensure that rotating machines operate without excessive bearing loads, vibration, and dynamic stresses, their design must consider rotordynamic response and provisions for mass balancing of rotors, even when their rotational speeds are modest. This paper presents a rotordynamics design study for a 1.4 MW, partially superconducting electric machine proposed for electrified aircraft propulsion – NASA’s High Efficiency Megawatt Motor (HEMM). The study includes the selection of mass balancing grade and mount and bearing stiffnesses to yield satisfactory critical speeds, deflection, and unbalance force, and predictions of the expected mass unbalance caused by the superconducting rotor coils. The impact of the machine’s number of rotor poles on expected mass unbalance is also quantified. Design decisions and lessons learned are discussed.

hybrid electric aircraft↗

NASA NTRSDate not supplied

Design and Development of a Fluid Immersion Cooled, SiC MOSFET, 37.5 kW, Bi-Directional Motor Converter

NASA's SUb-sonic Single Aft eNgine (SUSAN) aircraft is a concept aircraft whose architecture is that of a subsonic regional jet transport aircraft. SUSAN contains a single turbofan engine coupled to an electrified aircraft propulsion (EAP) system. To provide a path towards this goal, a 25% scale version of the SUSAN aircraft is being researched. A main component of the 25% power train is the Motor And Generator Intelligent Converter (MAGIC). This paper presents the design, development, and initial test results from MAGIC, a 37.5 kW, fluid immersion cooled, silicon carbide (SiC) MOSFET-based, bi-directional converter and controller.

PAO↗

NASA NTRSDate not supplied

Design and Development of a Fluid Immersion Cooled, SiC MOSFET, 37.5 kW, Bi-Directional Motor Converter

NASA's SUb-sonic Single Aft eNgine (SUSAN) aircraft is a concept aircraft whose architecture is that of a subsonic regional jet transport aircraft. SUSAN contains a single turbofan engine coupled to an electrified aircraft propulsion (EAP) system. To provide a path towards this goal, a 25% scale version of the SUSAN aircraft is being researched. A main component of the 25% power train is the Motor And Generator Intelligent Converter (MAGIC). This paper presents the design, development, and initial test results from MAGIC, a 37.5 kW, fluid immersion cooled, silicon carbide (SiC) MOSFET-based, bi-directional converter and controller.

Immersion↗

NASA NTRS2025

Airports as Energy Nodes Activity Summary

Advanced aircraft concepts that use non-traditional aviation energy storage methods such as batteries or cryogenic hydrogen are in development and expected to enter regular service at airports worldwide within the next decade. The energy needs for these aircraft may quickly overwhelm the existing energy infrastructure at airports, particularly at smaller and more remote facilities. Without energy upgrades, these airports will not be able to host these advanced vehicles, but without the advanced vehicle traffic, these airports will not have the rationale or funding to build up their energy infrastructure. The Airports as Energy Nodes (ÆNodes) activity, a collaboration between the National Aeronautics and Space Administration (NASA) and the National Renewable Energy Laboratory (NREL), was executed to understand and model the energy needs that advanced aircraft concepts may levy on these smaller airports, determine cost-effective approaches to enhance the airport energy infrastructure, and demonstrate the enhanced resilience of these energy infrastructure upgrades to the airport and surrounding community via “digital twin” simulation at relevant energy and dynamic time scales. The ÆNodes team also investigated future reference aircraft designs and materials to enable cryogenic hydrogen storage for aircraft. The ÆNodes team conducted analysis at two U.S. airport partner sites — Winchester Regional Airport in Winchester, Virginia, and Tweed/New Haven Airport in New Haven, Connecticut. The goal of this partnership was to develop data and reference infrastructure designs that could accommodate advanced aircraft in the future at these airports while also enhancing the resiliency of the energy supply to the surrounding airport community, which could be used to capture funding to enable the infrastructure upgrades. Over the course of the study, a method was developed to estimate air traffic requiring advanced energy services over the course of a year using a mix of historical data and companion studies on advanced aircraft transportation networks. The study has concluded at NASA but continues at NREL, who will develop a final report discussing the energy infrastructure upgrades and digital twin results. Preliminary results indicate that unrestricted adoption of advanced battery-electric aircraft may double traffic at these airports and increase peak daily power usage by an order of magnitude, while increase electricity energy needs by a factor of two to four. The infrastructure upgrades necessary to accommodate these increased energy needs could be used to provide enhanced energy services to the airport community to offset the cost and increase the utility of the upgrades, which will be described in the NREL final report.

Airports↗

NASA NTRS2024

AC and DC Fault Management for Megawatt Electrified Aircraft Electrical Powertrains - Task 2: Power Quality Filtering Using Nanocrystalline Soft Magnetic Inductor

The NASA RTAPS program on AC and DC Fault Management for Megawatt Electrified Power Train is a multi-year joint project with Pratt & Whitney (P&W), Collins Aerospace (CA), and RTX Technology Research Center (RTRC). This research program focuses on the high-voltage distribution issues that present a significant technological obstacle in the adoption of Electrified Aviation Propulsion (EAP) systems. One challenge to the adoption of high-voltage distribution systems with power electronic converters is the need for filter elements to limit the generation and propagation of noise, protect the cable systems from premature aging and prevent against excessive heating within subcomponents due to high-frequency induced currents. While increased distribution voltages aide in reducing the cable mass for a fixed power system, the associated mass with the filtering elements for power electronic converter can grow with increasing distribution voltages – thereby mitigating any benefit associated with increasing the distribution system voltage. To enable high-voltage distribution systems with high system specific power densities, new magnetic materials must be developed. Therefore, the second task of the NASA RTAPS program is associated with the design and application of advanced soft magnetic components for Megawatt class electric propulsion systems, specifically the motor drive system. This report covers the collaborative work between NASA Glenn Research Center (GRC), RTRC, P&W and CA in the development of three types of magnetic components over the span of the three-year program. These critical magnetic components are the DC side EMI filter, which limits the propagation of harmful electromagnetic noise to the rise of the distribution system, and the AC side damping with the dv/dt filter, which limits the fast rise time of the power electronic converter output voltage to limit the degradation on the cable/motor insulation systems. Each of these components are investigated from component level design and are optimized at the system level with a combined modelling and testing effort. In the final experimental evaluation of the NASA developed soft magnetic material with a dv/dt filter, a commercial-off-the-shelf (COTS) magnetic core and the GRC magnetic core are optimized and loaded at 320Arms to evaluate their difference in performance. After a run time of 30 minutes in a MW-class motor driver at RTRC, the NASA GRC cores were found to not only offer a lower temperature rise of nearly 25°𝐶, but also a reduction in measured core loss of 25% (12.75W to 9.5W).

Elecrified Aircraft Propulsion↗

NASA NTRS2022

Specific Power and Efficiency Projections of Electric Machines and Circuit Protection Exploration for Aircraft Applications

The purpose of this paper is to generate specific power and efficiency projections through the year 2050 for electric machines for aircraft applications. A general literature review was performed to identify the types of electric machines that are commonly used and which types have the biggest potential for future aircraft applications due to their high specific power and efficiency. A database with historical data was built to include parameters such as weight [kg], rated power [kW], specific power [kW/kg], RPM, efficiency, year, motor cooling type, application type and motor type to allow for trend identification and accurate projections. Once the data was gathered, multiple curve fits on the historical data were generated and extrapolated to produce the projections for specific power according to conservative, nominal and aggressive projection scenarios. A different process was followed for the efficiency projections due to the scattered nature of the data. A state of the art (SoA) value for efficiency was identified through literature review and was used to create the conservative, nominal and aggressive projections for the time frames of 2030, 2040, and 2050. The efficiency and the specific power projections of EMs for 2050 are 0.989 and 50kW/kg respectively. This paper will also be examining circuit protection as it is an additional component of electric powertrains.

electric machines↗

NASA NTRSDate not supplied

Failure Modes and Mitigation Strategies for a Turboelectric Aircraft Concept with Turbine Electrified Energy Management

The electrification of gas turbine engines represents a major step-change in aircraft propulsion systems commonly known as Electrified Aircraft Propulsion (EAP). EAP involves the integration of electric machines potentially functioning as generators for large scale power extraction, as motors providing electrical augmentation of the engine spools, and even as a means of driving propulsors beyond the immediate scope of the engine. It may also include the use of energy storage. These and other characteristics of hybrid electric propulsion systems are relatively new to aircraft propulsion. The expanded propulsion architecture can be leveraged to improve propulsive efficiency and achieve better vehicle aerodynamics and controllability. It can also allow for additional benefits such as those enabled through Turbine Electrified Energy Management (TEEM). As the propulsion system and its functions expand, new failure modes are introduced. Due to the highly coupled nature of the propulsion system, failures could propagate throughout the system in ways that are unique to the new EAP architectures. To build confidence in the safety and practicality of EAP concepts, these failure modes need to be identified, explored, and addressed through mitigation strategies. This paper seeks to evaluate failure modes and failure mitigation strategies for the EAP concept known as the Single aisle Turboelectric AiRCaft with Aft Boundary Layer propulsor (STARC-ABL). The TEEM control concept is applied to improve transient operability. Several failure modes are considered and control based failure mitigation strategies are proposed with the goal of retaining operability and overall thrust. The results demonstrate the ability to maintain operability and a substantial amount of thrust in the event of various types of failures. Some challenges are also identified and discussed.

Turbine Electrified Energy Management↗

NASA NTRSDate not supplied

Control Architecture for a Concept Aircraft with a Series/Parallel Partial Hybrid Powertrain and Distributed Electric Propulsion

Traditional aircraft propulsion control approaches are insufficient for electrified aircraft powertrains due to their increased complexity compared to current systems. New control approaches are required to manage the increased interdependency and complexity of these electrified powertrains. Additionally, electrification enables aircraft to have multiple distributed thrust producing fans that the flight control system can leverage for enhanced maneuverability, further increasing the control complexity. This paper describes the control architecture for a concept vehicle with these characteristics, the SUbsonic Single Aft eNgine (SUSAN) Electrofan. SUSAN is a series/parallel partial hybrid electric single-aisle transport aircraft that leverages its electrified powertrain to provide fuel burn and emissions benefits when compared to the state-of-the-art. Achieving these benefits requires an appropriately designed control architecture that coordinates the various powertrain and flight control subsystems. As such, the SUSAN aircraft is designed with a high level of automation, allowing it to properly manage coupled subsystems and react rapidly to failures and anomalies. This paper presents a summary of the SUSAN powertrain design and discusses several of the novel control approaches used to manage the complex electrified powertrain.

Control↗

NASA NTRSDate not supplied

Control Architecture for a Concept Aircraft with a Series/Parallel Partial Hybrid Powertrain and Distributed Electric Propulsion

Traditional aircraft propulsion control approaches are insufficient for electrified aircraft powertrains due to their increased complexity compared to current systems. New control approaches are required to manage the increased interdependency and complexity of these electrified powertrains. Additionally, electrification enables aircraft to have multiple distributed thrust producing fans that the flight control system can leverage for enhanced maneuverability, further increasing the control complexity. This paper describes the control architecture for a concept vehicle with these characteristics, the SUbsonic Single Aft eNgine (SUSAN) Electrofan. SUSAN is a series/parallel partial hybrid electric single-aisle transport aircraft that leverages its electrified powertrain to provide fuel burn and emissions benefits when compared to the state-of-the-art. Achieving these benefits requires an appropriately designed control architecture that coordinates the various powertrain and flight control subsystems. As such, the SUSAN aircraft is designed with a high level of automation, allowing it to properly manage coupled subsystems and react rapidly to failures and anomalies. This paper presents a summary of the SUSAN powertrain design and discusses several of the novel control approaches used to manage the complex electrified powertrain.

Control↗

NASA NTRS2023

Control Architecture for a Concept Aircraft with a Series/Parallel Partial Hybrid Powertrain and Distributed Electric Propulsion

Traditional aircraft propulsion control approaches are insufficient for electrified aircraft powertrains due to their increased complexity compared to current systems. New control approaches are required to manage the increased interdependency and complexity of these electrified powertrains. Additionally, electrification enables aircraft to have multiple distributed thrust producing fans that the flight control system can leverage for enhanced maneuverability, further increasing the control complexity. This paper describes the control architecture for a concept vehicle with these characteristics, the SUbsonic Single Aft eNgine (SUSAN) Electrofan. SUSAN is a series/parallel partial hybrid electric single-aisle transport aircraft that leverages its electrified powertrain to provide fuel burn and emissions benefits when compared to the state-of-the-art. Achieving these benefits requires an appropriately designed control architecture that coordinates the various powertrain and flight control subsystems. As such, the SUSAN aircraft is designed with a high level of automation, allowing it to properly manage coupled subsystems and react rapidly to failures and anomalies. This paper presents a summary of the SUSAN powertrain design and discusses several of the novel control approaches used to manage the complex electrified powertrain.

Control↗

NASA NTRSDate not supplied

Power Optimal Control Allocation for Distributed Electric Propulsion in a Series/Parallel Hybrid Powertrain

This paper describes a thrust allocation scheme that minimizes power consumption in an electrified powertrain with Distributed Electric Propulsion. It takes advantage of an observation about component efficiency maps, that efficiency is often highest at high torque/high speed conditions. This optimal approach is demonstrated to satisfy total thrust and net yaw axis torque requirements, making it suitable for utilizing differential thrust for maneuvering.

electrified aircraft propulsion↗

NASA NTRSDate not supplied

Power Optimal Control Allocation for Distributed Electric Propulsion in a Series/Parallel Hybrid Powertrain

This paper describes a thrust allocation scheme that minimizes power consumption in an electrified powertrain with Distributed Electric Propulsion. It takes advantage of an observation about component efficiency maps, that efficiency is often highest at high torque/high speed conditions. This optimal approach is demonstrated to satisfy total thrust and net yaw axis torque requirements, making it suitable for utilizing differential thrust for maneuvering.

electrified aircraft propulsion↗

NASA NTRS2026

Power Optimal Control Allocation for Distributed Electric Propulsion in a Series/Parallel Hybrid Powertrain

This paper describes a thrust allocation scheme that minimizes power consumption in an electrified powertrain with Distributed Electric Propulsion. It takes advantage of an observation about component efficiency maps, that efficiency is often highest at high torque/high speed conditions. This optimal approach is demonstrated to satisfy total thrust and net yaw axis torque requirements, making it suitable for utilizing differential thrust for maneuvering.

electrified aircraft propulsion↗

NASA NTRS2023

Flight Simulator Demonstration and Certification Implications of Powertrain Failure Mitigation in a Partial Turboelectric Aircraft

The Single-aisle Turboelectric AiRCraft with Aft Boundary Layer propulsor (STARC ABL) is a concept aircraft with a partial turboelectric powertrain. The complexity and integrated nature of the partial turboelectric powertrain architecture presents failure modes and hazards not found in conventional aircraft propulsion designs. Previously, various electrical and mechanical faults and associated recovery modes were demonstrated in a dynamic model of the powertrain. It was shown that certain faults were catastrophic without recovery logic, due specifically to the interaction of the subsystems. However, in each case, the logic, known as a reversionary control mode, enabled continued operation with assumed sufficient thrust to maintain safe flight. The current work evaluates the powertrain faults and recovery strategies using a full aircraft model in a piloted flight simulator, and places it in the context of current regulatory practice. Faults initiated in flight were successfully mitigated, with the accommodated aircraft subsequently evaluated against certification requirements for three-engine aircraft, which were shown to be appropriate for the STARC-ABL configuration.

certification↗

NASA NTRSDate not supplied

Flight Deck Design of a Hybrid Turbine/Electric Aircraft

The SUbsonic Single Aft eNgine (SUSAN) program is being developed as a sustainable subsonic regional aircraft. NASA is conducting trade studies for this future hybrid single aisle passenger aircraft. The goal of reducing emission levels by 50% will be enabled through an advanced design. An aft mounted single turbine engine provides thrust and electric power to drive 16 wing mounted electric engines. Using the 16 counter-rotating electric fans will create an efficient, very high bypass ratio, engine. Electric engines allow for distributed thrust, reducing control surfaces and provide a greater dynamic response. Batteries provide boost for takeoff and climb, allowing a smaller, more efficient, turbine engine. As part of the SUSAN effort, two pilot-in-the-loop studies were conducted at NASA Langley Research Center in Virginia to explore flight deck design issues. In particular: how many throttles are required/desired for a 17-engine aircraft, does the hybrid electric design change the answer, what are the requirements for electric engine displays, what system pages are required, and what information is required to monitor the batteries. Objective and subjective data were collected after each scenario and at the end of the day with a guided set of questionnaires from sixteen crews paired by airline. Data along with pilot comments were used to improve the throttle and engine displays between the studies and used to make the final recommendations on flight deck configurations. This paper provides final design recommendations for the SUSAN flight deck and justification for each recommendation.

PAI↗

NASA NTRSDate not supplied

NASA Interests in Superconducting and Cryogenic Technology

NASA develops and operates technology for a wide range of applications and environments across its aeronautics and space portfolios. This presentation will summarize the applications and environments where superconducting technology and associated cryogenics are contributing to NASA’s missions and areas where there is an opportunity to expand the contribution. Important characteristics of high priority space environments will be discussed. An emphasis will be placed on aircraft propulsion and NASA’s Artemis mission (a Moon to Mars initiative). The discussion of space applications will include takeaways from NASA’s recent rankings of 187 space technology “shortfalls”. The aircraft propulsion application will be described in detail and existing NASA investments will be summarized.

Electrified Aircraft Propulsion↗

NASA NTRSDate not supplied

Preliminary Dynamic Modeling of the Quarter-Scale Distributed Electric Propulsion Aircraft

This paper describes the early-stage modeling of a quarter-scale distributed electric propulsion aircraft, based on the SUbsonic Single Aft eNgine (SUSAN) Electrofan, a transformative concept aircraft for which a model exists. The full-scale 180 passenger SUSAN concept has a single turbofan engine in the tail that both produces thrust and provides electrical power to 16 electric fans distributed across the wings utilizing a series/parallel hybrid architecture. The quarter-scale version would have an internal combustion piston engine to provide power to 17 electric fans–16 on the wings, one in the tail–in a series hybrid configuration, and no vertical or horizontal stabilizers. It would also have a reduced flight envelope in terms of both altitude and speed. The initial modeling approach is to scale down the original airframe model to capture the dynamic behavior of a much smaller aircraft, albeit with an empennage. The original powertrain model is then replaced with one representing the physical components of that of the quarter-scale vehicle. This powertrain model is suitable for control design and analysis, and the fully integrated, although preliminary, aircraft model allows flight simulator testing and evaluation. Results from simulations are presented.

electrified aircraft propulsion↗