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At least 1,333 records · Page 74

Space station WP-04 power system preliminary analysis and design document, volume 3

Rocketdyne plans to generate a system level specification for the Space Station Electric Power System (EPS) in order to facilitate the usage, accountability, and tracking of overall system level requirements. The origins and status of the verification planning effort are traced and an overview of the Space Station program interactions are provided. The work package level interfaces between the EPS and the other Space Station work packages are outlined. A trade study was performed to determine the peaking split between PV and SD, and specifically to compare the inherent total peaking capability with proportionally shared peaking. In order to determine EPS cost drivers for the previous submittal of DRO2, the life cycle cost (LCC) model was run to identify the more significant costs and the factors contributing to them.

Source record↗

Validation of the NASA Electrical Power System – Sizing and Analysis Tool (EPS-SAT)

The electrification of aircraft propulsion systems has opened the design space for engineers by allowing for unique and highly specialized propulsion system and vehicle designs. NASA developed the Electrical Power System – Sizing and Analysis Tool (EPS-SAT) to conduct high-level trade studies and sensitivity studies on the various propulsion system designs that can be implemented in electrified aircraft. The results of these studies would be used to better direct investment dollars and determine strengths and weaknesses of propulsion system designs. In this paper, the results of the EPS-SAT tool were validated with hardware data extracted from the NASA Revolutionary Vertical Lift Technology (RVLT) Advanced Reconfigurable Electric Aircraft Lab (AREAL). Updated performance maps were added to the EPS-SAT library so that high-fidelity results could be calculated.

Patrick A. Hanlon↗

Machine Learning in Power System Operations: Training Data

Reliability and stability of the electric grid today has depended upon operations of the grid which include the protective relay. Today, the electricity sector faces new challenges with the shift of generation resource characteristics away from the traditional “big iron” generation to inverter-based resources (IBR) which shift the physics and assumption used in grid operation and protection. These changing conditions represent new challenges for protective relays (identification of faults) and increased challenges for protection engineers (correct settings and configuration, reduction of mis-operations), both issues recognized in research and industry. Finding new approaches to reduce mis-operations in relaying and new approaches to fault identification is critical to grid operations. Using today’s modern technology of embedded systems, edge computing, machine learning (ML), and communications we can help address challenges and augment and improve on existing power system operations methodologies.

24 POWER TRANSMISSION AND DISTRIBUTION↗

Relation of the lunar power system to the SEI program and to landers

The people of Earth will need more than 20,000 billion watts (GWe) of electric power by 2050 for a high level of prosperity. Power needs in the 22nd Century could exceed 100,000 GWe. By 2100 the total quantity of thermal energy used could fully deplete the known inventory (10(exp 7) GWt-Y) of all non-renewable sources on Earth except for deuterium and hydrogen for use in proposed fusion reactors. The labor, capital, and mass of power plants required to produce 1 GWe-Y of energy from present-day power plants is summarized. Fossil and nuclear plants respectively consume 80 to 190 M$ and 12 to 48 M$ of fuel per GWe-Y. The Lunar Power System (LPS) uses solar power bases on the moon to beam electric power to Earth. The LPS in the figure supplies load-following power to rectennas on Earth. Additional solar power conversion units are located across the lunar limb from their respective Earthward transmitting stations. LPS can be augmented by mirrors in polar orbit about the moon. The construction of rectennas on Earth determines the base cost (0.001s$/kWe-H) of LPS power. A manned International Lunar Base (ILB) can accelerate the development of LPS by providing the initial transportation and habitation facilities and base operations. ILB can greatly reduce up front costs and risks by emplacing a moderate scale LPS (1-100 GWe). LPS can accelerate the development of the ILB by providing greater funding than is reasonable to expect for purely scientific research. An international ILB/LPS program can foster world trust and prosperity.

Criswell, David R.↗

Multimegawatt nuclear power system for lunar base applications

This report describes a conceptual design for a multimegawatt lunar-based nuclear power system developed by students in the Space Systems Design course at the University of Washington. The design requirements are to produce 3 MWe for an operational lifetime of 10 years without human intervention. The system utilizes an inert-gas-cooled fuel-pin reactor as the heat source, a regenerative Brayton cycle as the power converter and a liquid droplet radiator as the thermal management system, and has a specific power of 66 W/kg. The unique requirements of a lunar base on shielding and siting of a nuclear reactor are discussed. The structural elements, though large, have a relatively small total mass and the liquid droplet radiator is highly adaptable to the moon due to the positive effects of lunar gravity on the droplet collection process.

Panchyshyn, M.↗

A modular Space Station/Base electrical power system - Requirements and design study.

The requirements and procedures necessary for definition and specification of an electrical power system (EPS) for the future space station are discussed herein. The considered space station EPS consists of a replaceable main power module with self-contained auxiliary power, guidance, control, and communication subsystems. This independent power source may 'plug into' a space station module which has its own electrical distribution, control, power conditioning, and auxiliary power subsystems. Integration problems are discussed, and a transmission system selected with local floor-by-floor power conditioning and distribution in the station module. This technique eliminates the need for an immediate long range decision on the ultimate space base power sources by providing capability for almost any currently considered option.

Eliason, J. T.↗

Physics-guided Deep Learning for Power System State Estimation

In the past decade, dramatic progress has been made in the field of machine learning. This paper explores the possibility of applying deep learning in power system state estimation. Traditionally, physics-based models are used including weighted least square (WLS) or weighted least absolute value (WLAV). These models typically consider a single snapshot of the system without capturing temporal correlations of system states. In this paper, a physics-guided deep learning (PGDL) method is proposed. Specifically, inspired by autoencoders, deep neural networks (DNNs) are used to learn the temporal correlations. The estimated system states from DNNs are then checked against physics laws by running through a set of power flow equations. Hence, the proposed PGDL is both data-driven and physics-guided. The accuracy and robustness of the proposed PGDL method are compared with traditional methods in standard IEEE cases. Simulations show promising results and the applicability is further discussed.

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Analysis of the Artemis I Orion Spacecraft Power System Performance

NASA successfully completed an uncrewed test flight of the Orion spacecraft during the 26-day Artemis I mission in November and December 2022. The Artemis I mission profile included several potentially stressing features for Orion electrical power system (EPS) performance, including eclipse duration, multiple propulsive or navigational maneuvers which constrained positioning of the solar array wings (SAWs), and the proximity and phasing of various events together. All of these features vary significantly with Earth-sun-moon geometry, providing a unique challenge for predicting EPS performance before an exact launch date is known. This presentation will provide a brief mission overview, discuss the different computer models with varying levels of fidelity used to analyze Orion EPS performance, as well as the screening process developed to incorporate EPS performance as a consideration for launch epoch selection. Final preflight model predictions of EPS performance will be compared to in-flight telemetry measurements, and several EPS anomalies observed will be briefly discussed.

Orion↗

Power System Overview for the Small RPS Centaur Flyby and the Mars Polar Hard Lander NASA COMPASS Studies

The NASA Glenn Research Center (GRC) Radioisotope Power System Program Office (RPSPO) sponsored two studies lead by their mission analysis team. The studies were performed by NASA GRCs Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team. Typically a complete toplevel design reference mission (DRM) is performed assessing conceptual spacecraft design, launch mass, trajectory, science strategy and sub-system design such as, power, propulsion, structure and thermal.

Space Missions↗

Small reactor power system for space application

A development history and comparative performance capability evaluation is presented for spacecraft nuclear powerplant Small Reactor Power System alternatives. The choice of power conversion technology depends on the reactor's operating temperature; thermionic, thermoelectric, organic Rankine, and Alkali metal thermoelectric conversion are the primary power conversion subsystem technology alternatives. A tabulation is presented for such spacecraft nuclear reactor test histories as those of SNAP-10A, SP-100, and NERVA.

Shirbacheh, M.↗

Space station electric power system requirements and design

An overview of the conceptual definition and design of the space station Electric Power System (EPS) is given. Responsibilities for the design and development of the EPS are defined. The EPS requirements are listed and discussed, including average and peak power requirements, contingency requirements, and fault tolerance. The most significant Phase B trade study results are summarized, and the design selections and rationale are given. Finally, the power management and distribution system architecture is presented.

Teren, Fred↗

Space Station electric power system requirements and design

An overview of the conceptual definition and design of the Space Station Electric Power System (EPS) is given. Responsibilities for the design and development of the EPS are defined. The EPS requirements are listed and discussed, including average and peak power requirements, contingency requirements, and fault tolerance. The most significant Phase B trade study results are summarized, and the design selections and rationale are given. Finally, the power management and distribution system architecture is presented.

Teren, Fred↗