Test requirements of electric propulsion systems leading to extended flight time missions.
Test program philosophy of electric propulsion and power for planetary mission application
TEST PROGRAM↗
SEARCH · Engineering Papers
Results for “electricity systems”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Development of solid propellant electric thruster systems for attitude control and station keeping of spacecraft.
Solid propellant electric thrustor /SPET/ using pulse plasma for spacecraft attitude control and stationkeeping
THRUSTOR↗
Planetary Mission Capability of Small Low Power Solar Electric Propulsion Systems
Planetary mission performance is presented for small, low power Solar Electric Propulsion spacecraft launched on a Delta II (7925) launch vehicle. The planetary missions presented in this paper are those that appear most attractive for a small, low-cost, solar electric propulsion mission.
power comet rendevous asteroid belt rendevous↗
Benefits of Application of Advanced Technologies for a Neptune Orbiter, Atmospheric Probes and Triton Lander
Missions with planned launch dates several years from today pose significant design challenges in properly accounting for technology advances that may occur in the time leading up to actual spacecraft design, build, test and launch. Conceptual mission and spacecraft designs that rely solely on off the shelf technology will result in conservative estimates that may not be attractive or truly representative of the mission as it actually will be designed and built. This past summer, as part of one of NASA s Vision Mission Studies, a group of students at the Laboratory for Spacecraft and Mission Design (LSMD) have developed and analyzed different Neptune mission baselines, and determined the benefits of various assumed technology improvements. The baseline mission uses either a chemical propulsion system or a solar-electric system. Insertion into orbit around Neptune is achieved by means of aerocapture. Neptune s large moon Triton is used as a tour engine. With these technologies a comprehensive Cassini-class investigation of the Neptune system is possible. Technologies under investigation include the aerocapture heat shield and thermal protection system, both chemical and solar electric propulsion systems, spacecraft power, and energy storage systems.
Somers, Alan↗
Transmission mounted electrical charging system and dual driveline load coupling
A system includes a PTO device that selectively couples to a driveline of a vehicle at each of two driveline coupling positions, and a motor/generator electrically coupled to an electrical power storage system. The system further includes a shared load selectively powered by the driveline or the motor/generator. The PTO device further includes a coupling actuator that couples the shared load to the motor/generator in a first position, and couples the shared load to the driveline in a second position.
Fortune, Glenn Clark↗
A comparison of Stirling engines for use with a 25 kW dish-electric conversion system
Two designs for an advanced Stirling conversion system (ASCS) are described. The objective of the ASCS is to generate about 25 kW of electric power to an electric utility grid at an engine/alternator target cost of $300.00/kW at the manufacturing rate of 10,000 unit/yr. Both designs contain a free-piston Stirling engine (FPSE), a heat transport system, solar receiver, a means to generate electric power, the necessary auxiliaries, and a control system. The major differences between the two concepts are: one uses a 25 kWe single-piston FPSE which incorporates a linear alternator to directly convert the energy to electricity on the utility grid; and in the second design, electrical power is generated indirectly using a hydraulic output to a ground based hydraulic motor coupled to a rotating alternator. Diagrams of the two designs are presented.
Shaltens, Richard K.↗
Misalignment Tolerant Three-phase Wireless Fast Charging System for Electric Vehicles
This project proposes improving the technology level of the three-phase wireless charging technology developed at Oak Ridge National Laboratory (ORNL). Successful commercialization of wireless charging systems require that they meet strict safety standards for electromagnetic field emissions and interoperability with other wireless charging technology. ORNL has previously demonstrated a 50kW three-phase wireless power transfer system with 95% efficiency. This prototype system weighed less than 50% of similar high-power wireless charging system while simultaneously exhibiting better safety characteristics. Due to better material utilization, the reduction in mass is expected to translate into similar cost reduction for the magnetic coupler. Additionally, the smaller footprint of the system can ease vehicle integration difficulties that would be encountered using other technology. Furthermore, the three-phase design can be made to operate with existing single-phase coupler design more easily and without intentional physical misalignment which would otherwise pose safety issues.This project developed ORNL’s WPT technology to satisfy the specifications and requirements for electric vehicle (EV) charging. The result of the project will be a prototype and reference design for a high-power wireless charging system—including magnetics, power electronics, and controls—serving as a baseline for product development.
33 ADVANCED PROPULSION SYSTEMS↗
Control of energy storage to reduce electric power system off-nominal frequency deviations
A hybrid power generation system is formed by the combination of an energy storage system (ESS) and a rotating synchronous power generator (SPG). Energy is stored in or released from the ESS in response to measurements of the at least one angle parameter, selected from rotor, torque, or power angle of the SPG, to provide active frequency damping of electrical power output. The control of ESS energy exchange increases the stabilizing impact of the SPG inertia on the frequency of electricity in an electrical network or power grid. The hybrid power generation system can have an effective equal area criterion for stability limit that is greater than that of the SPG operating without the ESS. The hybrid power generation system can enable the electrical network to have a greater proportion of variable or distributed energy resource (DER) power generation systems without otherwise exceeding stability limits.
Vartanian, Charles K.↗
Testing requirements of electric propulsion systems leading to extended flight-time missions.
Test program philosophy of electric propulsion and power for planetary mission application
ELECTRIC PROPULSION↗
Thermionic spacecraft design study, 120 kw nuclear electric propulsion system. Volume 2: External fuel reactor spacecraft design
Design and development of electrically propelled spacecraft based on external-fuel reactor concepts for thermionic reactors - Vol. 2
Source record↗
Solar Electric Propulsion System Integration Technology (SEPSIT). Volume 1: Technical summary
The use of solar electric propulsion as a means of exploring space beyond the reach of ballistic missions was investigated. The method used was to study the application of this new propulsion technology to a future flight project. A 1980 Encke rendezvous mission was chosen because a design successful for Encke could be used for less difficult, but scientifically rewarding, missions. Design points for the mission and for the thrust subsystem were specified. The baseline-vehicle design was defined. A preliminary functional description document for the thrust subsystem was originated. Analyses were performed in support of the design point selection for the SEP-module thrust subsystem to specify parameters, to clarify and optimize the interface requirements, and to assure feasibility of some of the more critical technological aspects of SEP application.
Gardner, J. A.↗
Bulk Electric Power System Risks From Coordinated Edge Devices
Not Available
24 POWER TRANSMISSION AND DISTRIBUTION↗
Instrumentation for Assessing DC Electrical Distribution Systems in Buildings
Direct current (DC) distribution systems is emerging as a favorable option over alternating current in buildings due to its energy and non-energy benefits (e.g., efficiency, resilience, safety). However, limited guidelines exist to evaluate the DC electrical distribution infrastructure. This paper aims to fill that gap by detailing our experience with metering a building-level electrical DC distribution system. Our case study is a DC microgrid at the Direct Energy Partners Research & Development facility located in Charlotte, North Carolina. This paper presents our approach, technical challenges, and lessons learned with DC metering and instrumentation.
buildings↗
Analysis of Near Rectilinear Halo Orbit Insertion with a 40-kW Solar Electric Propulsion System
This paper examines low thrust trajectories for delivery of a 40-kW solar electric propulsion spacecraft and potential additional payload to a desired NRHO. One option considered is a trans-lunar injection launch as a co-manifested payload on the Space Launch System. For this option, a reference trajectory is designed and a scan of launch dates is completed to understand the propellant mass sensitivity. A 15-day period cyclical variation in required propellant is observed that is attributed to solar gravity effects. A second option considered is to launch on a smaller commercial launch vehicle to a less energetic elliptical orbit and use SEP to spiral out to NRHO. For this option, analysis is completed to understand the trades between delivered mass to NRHO, total propellant required, time of flight, and solar array degradation. Results show that, while launching to lower altitudes can deliver greater payload mass to NRHO, significant solar array degradation can be observed.
Trajectory↗
Analysis of Near Rectilinear Halo Orbit Insertion with a 40-kW Solar Electric Propulsion System
This paper examines low thrust trajectories for delivery of a 40-kW solar electric propulsion spacecraft and potential additional payload to a desired NRHO. One option considered is a trans-lunar injection launch as a co-manifested payload on the Space Launch System. For this option, a reference trajectory is designed and a scan of launch dates is completed to understand the propellant mass sensitivity. A 15-day period cyclical variation in required propellant is observed that is attributed to solar gravity effects. A second option considered is to launch on a smaller commercial launch vehicle to a less energetic elliptical orbit and use SEP to spiral out to NRHO. For this option, analysis is completed to understand the trades between delivered mass to NRHO, total propellant required, time of flight, and solar array degradation. Results show that, while launching to lower altitudes can deliver greater payload mass to NRHO, significant solar array degradation can be observed.
Mccarty, Steven L.↗
Analytical study of electrical disconnect system for use on manned and unmanned missions
The program to survey existing electrical connector availability, and establish an optimum connector design for maintainable spacecraft substation interfaces is reported. Functional and operational requirements are given along with the results of the documentation survey, which disclosed that the MSFC series connectors have the preferred features of current connector technology. Optimum design concepts for EVA tasks, modules serviced by manipulators, and for manipulators independent of other servicing units are presented. It is concluded that separate connector designs are required for spacecraft replaceable modules, and for crewman EVA.
Rosener, A. A.↗
Renewable Energy and Efficiency Technologies in Scenarios of U.S. Decarbonization in Two Types of Models: Comparison of GCAM Modeling and Sector-Specific Modeling
Energy system projections from quantitative models inform actions ranging from short-term and local decisions, such as those about technology and infrastructure deployment, and global and long-term negotiations and targets. Computational limits require model designers to balance coverage and resolution (i.e., breadth versus depth). Some models, such as the Global Change Analysis Model (GCAM), represent all energy sources and uses with less resolution than models that focus on a single sector's energy use. GCAM balances global supply and demand of all energy carriers projecting prices using internal calculations for energy sources and costs of greenhouse gas mitigation while capturing interlinkages between the energy system, water, agriculture and land use, the economy, and the climate. This globally comprehensive model was used to frame the Long-Term Strategy of the United States: Pathways to Net-Zero Greenhouse Gas Emissions by 2050, which the White House released in 2021 and has been used to inform national and global economy-wide climate change mitigation discussions and strategy development for decades. Unlike GCAM, sectoral models focus on a portion of the energy sector and with greater detail and resolution. The Regional Energy Deployment System (ReEDS) electricity-sector model, for example, projects electricity system capacity expansion and operation with high-fidelity representation of emerging technologies for deep decarbonization, such as variable renewable energy and energy storage, and integration of these technologies into the electric grid. The Transportation Energy and Mobility Pathway Options (TEMPO) transportation-sector model enables analysis of household choices, with a focus on adoption, charging, and use of electric vehicles. The Scout buildings-sector model supports detailed consideration of the policies and markets that can accelerate the adoption of electrification and energy conservation measures in buildings. Such sector-specific models are instrumental in informing technology research, sectoral planning strategies, and sector-specific aspects of greenhouse gas mitigation strategies in the United States. The integrated multisector and sector-specific modeling approaches represented by GCAM and these sectoral models are complementary. The integrated multisector approach calculates energy pricing and resource allocation within the model, which is important for consistency when future conditions substantially diverge from current conditions in transformative scenarios. The sector-specific approach facilitates representation of granular details across spatial, temporal, technological, and market dimensions that enable exploration of particular interactions and trade-offs. This report presents the results of recent work to explore the differences and trade-offs between these approaches by comparing GCAM with the sector-specific ReEDS, TEMPO, and Scout models. The report compares both model structures and results, and it addresses their potential relevance and applications.
29 ENERGY PLANNING, POLICY, AND ECONOMY↗
300-kW Solar Electric Propulsion System Configuration for Human Exploration of Near-Earth Asteroids
The use of Solar Electric Propulsion (SEP) can provide significant benefits for the human exploration of near-Earth asteroids. These benefits include substantial cost savings - represented by a significant reduction in the mass required to be lifted to low Earth orbit - and increased mission flexibility. To achieve these benefits, system power levels of 100's of kW are necessary along with the capability to store and process tens of thousands of kilograms of xenon propellant. The paper presents a conceptual design of a 300-kW SEP vehicle, with the capability to store nearly 40,000 kg of xenon, to support human missions to near-Earth asteroids.
high-power↗