Joint Estimation of Operational Topology and Outages for Unbalanced Power Distribution Systems
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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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A Comprehensive Scheduling Framework using SP-ADMM for Residential Demand Response with Weather and Consumer Uncertainties
This paper presents a comprehensive scheduling framework for residential demand response (DR) programs considering both the day-ahead and real-time electricity markets. In the first stage, residential customers determine the operating status of their responsive devices such as heating, ventilation, and air conditioning (HVAC) systems and electric water heaters (EWHs), while the distribution system operator (DSO) computes the amount of electricity to be purchased in the day-ahead electricity market. In the second stage, the DSO purchases insufficient (or sells surplus) electricity in the real-time electricity market to maintain the supply-demand balance. Due to its computational complexity and data privacy issues, the proposed model cannot be directly solved in a centralized manner, especially with a large number of uncertain scenarios. Therefore, this paper proposes a combination of stochastic programming (SP) and the alternating direction method of multipliers (ADMM) algorithm, called SP-ADMM, to decompose the original model and then solve each sub-problem in a distributed manner while considering multiple uncertain scenarios. The simulation study is performed on the IEEE 33-bus system including 121 residential houses. Here, the results demonstrate the effectiveness of the proposed approach for large-scale residential DR applications under weather and consumer uncertainties.
24 POWER TRANSMISSION AND DISTRIBUTION↗
Characterization of Infrared Diode Laser Beams and Atmospheric CO Imaging Instrument
During June-August 1997 Dr. Jonathan Miles participated in the ASEE-sponsored summer faculty research program at NASA Langley Research Center (LaRC). The Aerospace Electronic Systems Division (AESD), Sensor Systems Branch (SSB), at NASA LARC had proposed a new mission, GEOstationary TROpospheric Pollution SATellite (GEO TROPSAT), to address critical science questions of tropospheric chemistry. The troposphere is a complex system, comprising "point" and distributed sources of natural and anthropogenic origin; complicated transport processes, both lateral and vertical; and photochemistry driven by UV flux, temperature, atmospheric composition, and other variables. GEO TROPSAT would be implemented about a geostationary Earth orbital (GEO) position at the equator between 600 and 80" West longitude to observe the Americas and large portions of the oceans of either coast. This mission would advance our knowledge of the atmosphere by capturing the wide temporal and spatial variability of tropospheric phenomena which is undetectable from low Earth orbit. A pre-prototype imaging carbon monoxide (CO) imaging system operating within a narrow waveband about 4.7 [Lm was built, demonstrated, and evaluated. This system applies the gas-filter correlation radiometry (GFCR) technique and produces digitized images comprising 4096 pixels, each representing a single CO mixing ratio measurement inferred from radiometric data. Associated tasks accomplished included specification for the next-generation prototype system to operate in the 2.3-@tm waveband; characterization of a 64x64, InSb focal-plane-array (FPA) imager; design, fabrication, and assembly of a filter wheel; and software development. Laboratory evaluation of this system involved imaging of a test cell placed in the path of radiant flux emanating from a blackbody source used to simulate the radiant energy reflected by Earth in real application. The cell was evacuated for system balancing and then charged with measured quantities of CO to provide a means for system characterization. Two related research efforts were undertaken during the term of the study reported here - continued development of an atmospheric CO imaging instrument and characterization of diode-laser beams. Both efforts were successful and are described within the body of this report. A second objective was to provide a means for undergraduate ISAT majors to become involved with the research described, to be afforded the opportunity to learn the technologies associated with the work performed. Two ISAT students gained a comprehensive understanding and interest in missions supported by NASA through direct involvement in this project. Many more students were exposed to these technologies through demonstrations, laboratory tours, and explanations provided in lectures.
Miles, Jonathan J.↗
A tool for assessing demand side management and operating strategies for isolated microgrids
Globally, power system operators are exploring ways to leverage the capabilities of smart meters to implement fine-grained demand side management (DSM). Here this paper presents a new simulation tool to evaluate operating strategies for smart-meter-enabled (SME) islanded microgrids being advanced for sustainable rural electrification in emerging economies. Based on MATLAB/Simulink, the tool's component-level models of small microgrids can be easily configured. Alternative rule-based operating strategies are implemented with controllable supply and storage components as well as other components driven by external factors (e.g., weather and time of day). To account for the wide range of possible operating conditions in real-world applications, statistical metrics can be evaluated using Monte Carlo (MC) methods based on user-defined, time-dependent probability distributions for demands, supplies, and environmental variables. Features of the tool are demonstrated with case studies for a representative microgrid in rural Rwanda.
24 POWER TRANSMISSION AND DISTRIBUTION↗
TRENDS: The aeronautical post-test database management system
TRENDS, an engineering-test database operating system developed by NASA to support rotorcraft flight tests, is described. Capabilities and characteristics of the system are presented, with examples of its use in recalling and analyzing rotorcraft flight-test data from a TRENDS database. The importance of system user-friendliness in gaining users' acceptance is stressed, as is the importance of integrating supporting narrative data with numerical data in engineering-test databases. Considerations relevant to the creation and maintenance of flight-test database are discussed and TRENDS' solutions to database management problems are described. Requirements, constraints, and other considerations which led to the system's configuration are discussed and some of the lessons learned during TRENDS' development are presented. Potential applications of TRENDS to a wide range of aeronautical and other engineering tests are identified.
Bjorkman, W. S.↗
An ice-motion tracking system at the Alaska SAR facility
An operational system for extracting ice-motion information from synthetic aperture radar (SAR) imagery is being developed as part of the Alaska SAR Facility. This geophysical processing system (GPS) will derive ice-motion information by automated analysis of image sequences acquired by radars on the European ERS-1, Japanese ERS-1, and Canadian RADARSAT remote sensing satellites. The algorithm consists of a novel combination of feature-based and area-based techniques for the tracking of ice floes that undergo translation and rotation between imaging passes. The system performs automatic selection of the image pairs for input to the matching routines using an ice-motion estimator. It is designed to have a daily throughput of ten image pairs. A description is given of the GPS system, including an overview of the ice-motion-tracking algorithm, the system architecture, and the ice-motion products that will be available for distribution to geophysical data users.
Kwok, Ronald↗
Transient SEUs in a fiber optic system for space applications
The results of an investigation on the SEU sensitivity for a fiber optic operating system are reported. Measurements were made on the upset cross sections for the system in static and dynamic modes of operation. The heavy ion SEU test facility at Brookhaven and the proton facility at Harvard University were used in this study. Cross sections were obtained for Honeywell transmitter and reciever devices operating in a system at a frequency of 100 kHz. Both devices were independently irradiated. The results show that the dynamic mode was the worst case, and the receiver was the most sensitive part type in the system. The threshold linear energy transfer (LET) for the receiver was determined to be 1.6 MeV sq cm/mg for the three input signals used in the tests, which were: a continuous high state, a low state, and a 100 kHz square wave.
Label, Ken↗
Expert system support for HST operations
An expert system is being developed to support vehicle anomaly diagnosis for the Hubble Space Telescope (HST). Following a study of safemode entry analyses, a prototype system was developed which reads engineering telemetry formats, and when a safemode event is detected, extracts telemetry from the downlink and writes it into a knowledge base for more detailed analyses. The prototype then summarizes vehicle events (limits exceeded, specific failures). This prototype, the Telemetry Analysis Logic for Operations Support (TALOS) uses the Lockheed Expert System (LES) shell, and includes over 1600 facts, 230 rules, and 27 goals. Although considered a prototype, it is already an operationally useful system. The history leading into the TALOS prototype will be discussed, an overview of the present TALOS system will be presented, and the role of the TALOS system in contingency planning will be delineated.
Cruse, Bryant↗
Intrusion Detection System Alarm Station Operator Interface Improvements
To address Alarm Station operator performance, Portable Intrusion Detection System team gathered information concerning AS operator data needs when assessing alarms. The purpose was to improve the Portable Intrusion Detection System operator interface to ensure that critical information was quickly presented and easily accessible. To gather the data, the team used a Goal Directed Task Analysis approach. The method of analysis was to prepare a set of interview questions, interview selected AS operator experts, conduct the interviews, create a goal/decision/information hierarchy based on information gathered, and then apply the results to the operator interface. In applying the results, the team had to consider not only the Goal Directed Task Analysis -determined information needs of the Alarm Station operator end-user population, but also account for customer requirements and differences in domain. The constraints in implementing all situation awareness recommendations are summarized and initial potential solutions presented.
98 NUCLEAR DISARMAMENT, SAFEGUARDS, AND PHYSICAL P↗
Global Positioning System Simulator Field Operational Procedures
Global Positioning System (GPS) simulation is an important activity in the development or qualification of GPS signal receivers for space flight. Because a GPS simulator is a critical resource it is highly desirable to develop a set of field operational procedures to supplement the basic procedures provided by most simulator vendors. Validated field procedures allow better utilization of the GPS simulator in the development of new test scenarios and simulation operations. These procedures expedite simulation scenario development while resulting in scenarios that are more representative of the true design, as well as enabling construction of more complex simulations than previously possible, for example, spacecraft maneuvers. One difficulty in the development of a simulation scenario is specifying various modes of test vehicle motion and associated maneuvers requiring that a user specify some (but not all) of a few closely related simulation parameters. Currently this can only be done by trial and error. A stand-alone procedure that implements the simulator maneuver motion equations and solves for the motion profile transient times, jerk and acceleration would be of considerable value. Another procedure would permit the specification of some configuration parameters that would determine the simulated GPS signal composition. The resulting signal navigation message, for example, would force the receiver under test to use only the intended C-code component of the simulated GPS signal. A representative class of GPS simulation-related field operational procedures is described in this paper. These procedures were developed and used in support of GPS integration and testing for many successful spacecraft missions such as SAC-A, EO-1, AMSAT, VCL, SeaStar, sounding rockets, and by using the industry standard Spirent Global Simulation Systems Incorporated (GSSI) STR series simulators.
Kizhner, Semion↗
Visions of the future operational meteorological satellite system
Visionary concepts of the operational environmental satellite system of the 1990's are presented. These exploit planned and anticipated advances in technology. The system comprises 8 Low Earth Orbitors (LEOS) at 500 km height for global coverage at 3 hourly intervals and 3 Geosynchronous Earth Orbitors (GEOS) for Western Hemisphere coverage with stereo capability and near simultaneous viewing of several regional areas. The LEOS emphasize passive and active microwave and Lidar sensing; the GEOS focus on high resolution visible and IR imaging and passive soundings. The GEOS also serve as data relays from the LEOS and as data collection platforms for hazard-related data. An integrated data management system ties the space fleet together and blends the data with that from all other observing systems to process and distribute the data and products to all users.
Atlas, D.↗
Considerations for a design and operations knowledge support system for Space Station Freedom
Engineering and operations of modern engineered systems depend critically upon detailed design and operations knowledge that is accurate and authoritative. A design and operations knowledge support system (DOKSS) is a modern computer-based information system providing knowledge about the creation, evolution, and growth of an engineered system. The purpose of a DOKSS is to provide convenient and effective access to this multifaceted information. The complexity of Space Station Freedom's (SSF's) systems, elements, interfaces, and organizations makes convenient access to design knowledge especially important, when compared to simpler systems. The life cycle length, being 30 or more years, adds a new dimension to space operations, maintenance, and evolution. Provided here is a review and discussion of design knowledge support systems to be delivered and operated as a critical part of the engineered system. A concept of a DOKSS for Space Station Freedom (SSF) is presented. This is followed by a detailed discussion of a DOKSS for the Lyndon B. Johnson Space Center and Work Package-2 portions of SSF.
Erickson, Jon D.↗
Optimal Load Ensemble Control in Chance-Constrained Optimal Power Flow
Distribution system operators (DSOs) world-wide foresee a rapid roll-out of distributed energy resources. From the system perspective, their reliable and cost effective integration requires accounting for their physical properties in operating tools used by the DSO. This work describes an decomposable approach to leverage the dispatch flexibility of thermostatically controlled loads (TCLs) for operating distribution systems with a high penetration level of photovoltaic resources. Each TCL ensemble is modeled using the Markov Decision Process (MDP). The MDP model is then integrated with a chance constrained optimal power flow that accounts for the uncertainty of PV resources. Since the integrated optimization model cannot be solved efficiently by existing dynamic programming methods or off-the-shelf solvers, this paper proposes an iterative Spatio-Temporal Dual Decomposition algorithm (ST-D2). Finally, we demonstrate the merits of the proposed integrated optimization and ST-D2 algorithm on the IEEE 33-bus test system.
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Experience of Implementing a Distributed Control System for Thermal and Mechanical and Electrical Equipment at the South-West CHP
Results of implementing an SPPA-T3000-based unified distributed control system for thermal and mechanical and electrical equipment at the South-West CHP are discussed. Hardware solutions for integration with local control systems, control of electrical equipment in compliance with the standards IEC 61850, Modbus RTU, and communication between the plant control system and the System Operator of the Unified Power System are described.
24 POWER TRANSMISSION AND DISTRIBUTION↗
Modeling the value of integrated U.S. and Canadian power sector expansion
The U.S.-Canadian power system has evolved into a highly integrated grid. Cross-border transmission and coordination of system operations create an interconnected power system with combined imports and exports of electricity of greater than 77 TWh per year. Currently, more than 5 GW of new international transmission lines are in various stages of permitting and development. These transmission lines may enable even greater integration and coordination of the U.S. and Canadian systems, which can in turn increase the reliability and flexibility of North America's electricity grid and help address challenges associated with integrating high levels of variable renewables. Using a version of the National Renewable Energy Laboratory's Regional Energy Deployment System (ReEDS) model that incorporates Canada, this analysis quantifies the differences in the evolution of the power system under scenarios in which cross-border transmission capacity is restricted to today's levels, and scenarios in which new transmission is less restricted. These impacts are analyzed under a 'business-as-usual' reference scenario and a scenario in which deep cuts in power sector carbon dioxide emissions levels are achieved. A set of key impact metrics is analyzed, including 1) the composition of generating capacity by technology, 2) system costs, 3) wholesale electricity prices, 4) international electricity exports and imports, 5) transmission capacity, and 6) carbon dioxide emission levels. When new cross-border transmission is not allowed, the United States needs additional capacity (primarily natural gas and renewable energy) to meet domestic needs, while total Canadian capacity is lower because less capacity is needed to export to the United States. This effect is amplified under the carbon cap scenario. Impacts vary on a regional basis, largely due to the different relative sizes of the generation portfolio between countries and regions and the relative impact from cross-border electricity trade. The total impact from restricting cross-border trade on carbon emissions and average wholesale electricity prices is limited, due to the relative size of the domestic power systems and the cross-border trade volume. Lastly, cross-border transmission capacity is projected to more than double under the unrestricted transmission capacity scenarios, which exceeds the rate of projected domestic transmission capacity additions in each country.
29 ENERGY PLANNING, POLICY, AND ECONOMY↗
A Polycrystalline Pd Surface Studied by Two-Dimensional Surface Optical Reflectance during CO Oxidation: Bridging the Materials Gap
Industrial catalysts are complex materials systems operating in harsh environments. The active parts of the catalysts are nanoparticles that expose different facets with different surface orientations at which the catalytic reactions occur. However, these facets are close to impossible to study in detail under industrially relevant operating conditions. Instead, simpler model systems, such as single crystals with a well-defined surface orientation, have been successfully used to study gas–surface interactions such as adsorption and desorption, surface oxidation, and oxidation/reduction reactions. To more closely mimic the many facets exhibited by nanoparticles and thereby close the so-called materials gap, there has also been a recent move toward using polycrystalline surfaces and curved crystals. However, these studies are limited either by the pressure or spatial resolution at realistic pressures or by the number of surfaces studied simultaneously. In this work, we demonstrate the use of reflectance microscopy to study a vast number of catalytically active surfaces simultaneously under realistic and identical reaction conditions. As a proof of concept, we have conducted an operando experiment to study CO oxidation over a Pd polycrystal, where the polycrystalline surface acts as a collection of many single-crystal surfaces. Finally, we visualized the resulting data by plotting the reflectivity as a function of surface orientation. We think the techniques and visualization methods introduced in this work will be key toward bridging the materials gap in catalysis.
36 MATERIALS SCIENCE↗
CPS Testbed Architectures for WAMPAC using Industrial Substation and Control Center Platforms and Attack-Defense Evaluation
Advanced persistent threats and cyberattacks can impact wide-area monitoring, protection, and control (WAMPAC) system operation. Many cyber-physical system (CPS) testbeds have been developed for attack-defense experimentation and attack-resiliency tools evaluation for WAMPAC, but they are limited to a simulation-and-emulation based environment. This paper presents a quasi-realistic CPS attack-defense testbed-based framework for WAMPAC applications using the industrial substation and control center platforms such as eTerra integrated with the hardware-in-the-loop CPS smart grid testbed available at Iowa State University. The proposed framework includes various combinations of industry-grade substation and control center platforms, communication topologies, real-time digital simulators, and a novel cyber-physical distributed intrusion-and-anomaly detection system (D-IADS) for WAMPAC applications. The D-IADS includes a master at the control center and geographically distributed sensor devices at each substation. Each D-IADS sensor deployed at a substation or control center network monitors ingress and egress traffic, detect intrusions, and dispatch alerts to the D-IADS master. The D-IADS master centrally monitors and analyze the alerts and controls D-IADS sensors. We considered an EMP60 synthetic CPS grid as a case study to demonstrate the framework and proposed D-IADS for WAMPAC applications against cyberattack vectors such as Man-in-the-Middle DNP3 attack, denial-of-service, and data-integrity attacks.
24 POWER TRANSMISSION AND DISTRIBUTION↗
Datum: A Scientific Metadata Catalog
The data catalog market is currently flooded with a myriad of different products, but none serve the scientific community well. There are cloud-native tools like Databricks, Snowflake,to on-premise solutions like Collibra and Datahub. The common failing of all these tools however, is their inability to serve the scientific data community directly. Most catalogs are targeted towards financial, health, or user data - not sensor or scientific domain data. They also prioritize integrations that often don’t exist or are just starting to be used in the scientific realm - all while ignoring common scientific tools and file types. Datum is a catalog which targets the scientific data directly, including the tools and networks in which those tools are used. We work with the producers and consumers of the data where they are, targeting cloud and on-premise with a focus on classified networks. Datum is an Erlang/Elixir application. Technical Features Note: The features listed below are still under development and may change, slightly, upon final delivery of the product. File Formats - Datum has the ability to read additional metadata and provides processing pipelines for the following file formats: Plain Text, PDF, LaTeX, HTML, Open Document Format (.odt), XML, CSV/TSV (and other standard delimiters), OpenDocument Database and Spreadsheets, Geo-Referenced TIFF, Common Data Format, HDF/HDF5, LabView TDMS, Excel, DeltaTables, Parquet, Apache Iceberg, Apache Hudi and many others. Metadata Collection - Scanners for the local and networked file systems and cloud storage providers. Network integration with common databases such as MSSQL and MySQL. User Plugin System - Users are able to provide either file processing, metadata extraction, or sampling plugins in the programming language of their choice. Authentication/Authorization -: OIDC integration, SCIM provisioning and EntraID integration out of the box. Full user and group management system with a “least privilege” operating mode. Governance - Customizable data governance platform; dictate and enforce required metadata, enforce data embargos, and enforce user agreements and NDAs before data access. Ability to create health checks on data, rejecting abandoned or poorly curated data and automatically removing it from the search index. Ability for users to submit corrections. Search - Semantic search is a first class citizen. No licenses to expensive, external software required. Integrated use of vectors and vector-based search allows for AI agent integration at all levels of operation. Metadata Model - Display and control data’s lineage and connections to other data and data directories. Data is modeled after a filesystem - an organization instantly recognizable and navigable by most any user. CLI and SDK - Ships with a Command Line Interface (CLI) tool and with a fully-featured Python SDK. This allows for rapid and programmatic use of Datum by every level of user. Minimal Infrastructure - Datum ships as a single executable file and can be run on any operating system and most CPU architectures. Datum has no reliance on external databases, search indexing tools, or other outside services - and it runs equally well on edge computing devices, cloud services, or in a clustered HPC environment.
darrington, john↗