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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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At least 1,297 records · Page 72
All sourcesNASA NTRSDOE OSTI
DOE OSTI2017

Optimal Coordinated EV Charging with Reactive Power Support in Constrained Distribution Grids

Electric vehicle (EV) charging/discharging can take place in any P-Q quadrants, which means EVs could support reactive power to the grid while charging the battery. In controlled charging schemes, distribution system operator (DSO) coordinates with the charging of EV fleets to ensure grid’s operating constraints are not violated. In fact, this refers to DSO setting upper bounds on power limits for EV charging. In this work, we demonstrate that if EVs inject reactive power into the grid while charging, DSO could issue higher upper bounds on the active power limits for the EVs for the same set of grid constraints. We demonstrate the concept in an 33-node test feeder with 1,500 EVs. Case studies show that in constrained distribution grids in coordinated charging, average costs of EV charging could be reduced if the charging takes place in the fourth P-Q quadrant compared to charging with unity power factor.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2018

Protection Coordination of an Inverter Generation Based Microgrid for an Unbalanced Distribution System

In this paper we examine the protection issues that must be dealt with, to successfully operate a microgrid when the utility experiences a grid outage. Changes in fault current levels within microgrids under grid-tied and islanded conditions present challenges to developing robust and reliable protection schemes. These schemes must provide an effective response in both grid-connected and islanded mode and the transition between these modes. In this study, a section of an actual residential community located in the western part of the United States (U.S.) was considered as part of the microgrid evaluation. A sizing analysis was conducted to select the appropriate sizes of DER; simulated using DER-CAM analysis. The two DERs considered for the study included solar PV and Battery Energy Storage System (BESS). This paper highlights the protection coordination issues when an existing unbalanced distribution system encompassing a residential subdivision is converted into a microgrid with generation sources with low fault contribution. It further explains the strategy to coordinate protection devices during grid connected and islanded microgrid operating regimes.

Bello, Mobolaji↗
DOE OSTI2019

Nonaqueous redox flow battery electrolyte comprising an ionic liquid with a metal cation coordinated to redox-active ligands

Nonaqueous redox flow batteries (RFB) hold the potential for high energy density grid scale storage, though are often limited by the solubility of the redox-active species in their electrolytes. A systematic approach enables an increase the concentration of redox-active species in electrolytes for nonaqueous RFB, starting from a metal-coordination-cation-based ionic liquid. As an example, starting with an ionic liquid consisting of a metal coordination cation (MetIL), ferrocene-containing ligands and iodide anions can be substituted into the original MetIL structure, enabling a nearly 4× increase in capacity compared to original MetIL structure. Application of this strategy to other chemistries, optimizing electrolyte melting point and conductivity could yield >10 M redox-active electrons.

Small, Leo J.↗
DOE OSTI2021

Coordination namespace processing

An approach is described that accesses data in a shared memory that is shared amongst nodes that include a local node and remote nodes. The local node receives a name corresponding to a named data element in a Coordination Namespace, the Coordination Namespace having been created in a memory distributed amongst the nodes. A hash function is applied to at least a portion of the name with a result of the hash function being a natural node indicator. Data corresponding to the named data element is requested from a natural node identified by the indicator. Based on the request, a response is received from the natural node.

Nair, Rishi↗
DOE OSTI2021

Coordinated Optimal Control of PV Inverters and HVAC Loads in Distribution Systems

The increasing integration of distributed energy resources (DERs), such as photovoltaics (PVs) and smart buildings into distribution systems complicate power system operation and controls. This paper proposes a coordinated optimal control strategy for PV inverters and Heating, ventilation, and air conditioning (HVAC) loads in smart buildings to minimize the total network loss in a distribution system. For the HVAC units, we enforce minimum on and off time constraints to avoid frequent switching that can degrade the unit. The proposed control will dispatch optimal control signals of active and reactive power to PV inverters and on/off commands to HVAC units while maintaining the nodal voltage within a secure range and the temperature of HVAC units at a comfort level. The simulation results on a modified IEEE 33-node distribution system demonstrate that the proposed coordinated control scheme can reduce the network loss.

Pani, Naveen↗
DOE OSTI2022

Access of named data elements in coordination namespace

An approach is described that provides access to a named data element in a Coordination Namespace that is stored in a memory that is distributed amongst a set of nodes. A request of a name corresponding to the named data element is received from a requesting process and the approach responsively searches for the name in the Coordination Namespace. In response to determining an absence of data corresponding to the named data element, a pending state is indicated to the requesting process. In response to determining that the data corresponding to the named data element exists, a successful state is returned to the requesting process. In one embodiment, the successful state also includes providing the requesting process with access to the data corresponding to the named data element.

97 MATHEMATICS AND COMPUTING↗
DOE OSTI2022

ADMS and DER Coordinated Capability Demonstrations to Assist Utilities to Increase Resilience and Reliability

The proliferation of distributed energy resources (DERs) presents opportunities and challenges to distribution grid operators. The National Renewable Energy Laboratory (NREL) and Survalent are collaborating to demonstrate advanced distribution management system (ADMS) and DER coordinated capability to assist utilities to increase resilience and reliability. ADMS and Distributed Energy Resource Management System (DERMS) Coordination for Peak Load Management (PLM). Fault Location, Isolation, and Service Restoration (FLISR) in the Presence of DERs. Grid-Edge Intelligent Distribution Automation System for Self-Healing Distribution Grids. These laboratory demonstrations use NREL's ADMS Test Bed.

ADMS↗
DOE OSTI2022

Coordinated voltage control and reactive power regulation between transmission and distribution systems

Systems and methods are described for coordinating volt-var control between sub-transmission and distribution systems. Distributed energy resources of a distribution system are aggregated into virtual power plants from which reactive power can optimally be dispatched to the sub-transmission system. A sub-transmission controller executes a volt-var AC optimal power flow optimisation function to minimize voltage fluctuations that might otherwise occur when coordinating with a distribution system having distributed energy resources. The distribution system can use a sensitivity matrix for regulating voltage at distribution feeders while fulfilling a transmission or sub-transmission system's demand requests.

Samaan, Nader A.↗
DOE OSTI2022

Sharing tuples across independent coordination namespace systems

A system and method for federating a tuple storage database across multiple coordinated namespace (CNS) extended memory storage systems allowing the sharing of tuples and tuple data across independent systems. The method provides a federation service for multiple coordination namespace systems. The method retrieves a tuple from connected independent CNS systems wherein a local CNS Controller sends a read request to the local gatekeeper to retrieve a first tuple and creates a local pending remote record. The local gatekeeper at a requesting node sends a broadcast query to a plurality of remote gatekeepers for the tuple and Remote gatekeepers at remote nodes query in its local CNS for the tuple. The Local gatekeeper process at the requesting node receives results from a plurality of remote gatekeepers for the said tuple and selects one remote gatekeeper to receive the requested tuple and broadcasts a read for tuple data with selected gatekeeper.

Jacob, Philip↗
DOE OSTI2017

Experimental study on team coordination of NPP plant operators based on the simultaneous NIRS measurements - 266

One of the key features when dealing with severe situations far beyond the previous experiences and expectations is the coordination capability among operators with different roles. In this study, the feasibility of estimating coordination capability of nuclear plant operators has been examined based on the correlation analysis of brain activities among operators. The cognitive experiments have been performed in the full scope NPP simulator at BWR Operator Training Center Cooperation. Four experienced instructors participated in the experiments. They played different roles such as shift supervisor, turbine operator, reactor operator and auxiliary operator and were instructed to go through four training scenarios shown below with NIRS devices attached. The brain activity of each operator has been measured along with the progress of anomaly events and the correlation of brain activities for every pair of operators have been calculated. The correlations of brain activities have also analyzed focusing on the specific events along with the progress in the anomaly scenarios. It has been shown in the results that the higher correlation among all operators were observed when the global events occurred and the higher correlation among specific pair of operators related to the specific event were partially observed. (authors)

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
DOE OSTI2021

Utah FORGE Updated Well, Well Pad, and Seismic Station GPS Coordinates December, 2021

This is a CSV spreadsheet containing UTM and Latitude and Longitude coordinates and elevations for Wells 78-32, 78B-32, 56-32, 58-32, 68-32, and 16A(78)-32 and seismic stations BOR1, BOR2, BOR3, FOR1, FOR2, FOR5, FOR6, FOR 7, FOR8, FORK, FORU, FORW, and FORB. These are from a GPS survey conducted by the Utah Geological Survey completed in December, 2021.

15 GEOTHERMAL ENERGY↗
DOE OSTI2021

Fluid Dynamics in Curvilinear Coordinates without Fictitious Forces

The use of curvilinear coordinates is sometimes indicated by the inherent geometry of a fluid dynamics problem, but this introduces fictitious forces into the momentum equations that spoil the strict conservative form. If one is willing to work in three dimensions, these fictitious forces can be eliminated by solving for rectangular (Cartesian) momentum components on a curvilinear mesh. A thoroughly geometric approach to fluid dynamics on spacetime demonstrates this transparently, while also giving insight into a greater unity of the relativistic and nonrelativistic cases than is usually appreciated.

pseudo-forces↗
DOE OSTI2018

Coordination chemistry of anticrowns. Synthesis and structure of a complex of cyclic trimeric perfluoro-o-phenylenemercury (o-C{sub 6}F{sub 4}Hg){sub 3} with tungsten hexacarbonyl

The reaction of the three-mercury anticrown (o-C{sub 6}F{sub 4}Hg){sub 3} (1) with tungsten hexacarbonyl in CH{sub 2}Cl{sub 2} at 20 °C in the dark affords the complex {[(o-C_6F_4Hg)_3]_2[W(CO)_6]} (2) containing two anticrown molecules per W(CO){sub 6} molecule. According to the X-ray diffraction data, two carbonyl groups of W(CO){sub 6} are involved in the formation of 2, each of these carbonyl groups being coordinated via the oxygen atom to a single mercury center of one of the two molecules 1. The formation of the complex is accompanied by a shift of ν(CO) bands in the IR spectrum with respect to the corresponding bands of the starting W(CO){sub 6}.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2014

The IAEA Coordinated Research Program on HTGR Uncertainty Analysis: Phase I Status and Initial Results

The continued development of High Temperature Gas Cooled Reactors (HTGRs) requires verification of HTGR design and safety features with reliable high fidelity physics models and robust, efficient, and accurate codes. One way to address the uncertainties in the HTGR analysis tools is to assess the sensitivity of critical parameters (such as the calculated maximum fuel temperature during loss of coolant accidents) to a few important input uncertainties. The input parameters were identified by engineering judgement in the past but are today typically based on a Phenomena Identification Ranking Table (PIRT) process. The input parameters can also be derived from sensitivity studies and are then varied in the analysis to find a spread in the parameter of importance. However, there is often no easy way to compensate for these uncertainties. In engineering system design, a common approach for addressing performance uncertainties is to add compensating margins to the system, but with passive properties credited it is not so clear how to apply it in the case of modular HTGR heat removal path. Other more sophisticated uncertainty modelling approaches, including Monte Carlo analysis, have also been proposed and applied. Ideally one wishes to apply a more fundamental approach to determine the predictive capability and accuracies of coupled neutronics/thermal-hydraulics and depletion simulations used for reactor design and safety assessment. Today there is a broader acceptance of the use of uncertainty analysis even in safety studies, and it has been accepted by regulators in some cases to replace the traditional conservative analysis. Therefore some safety analysis calculations may use a mixture of these approaches for different parameters depending upon the particular requirements of the analysis problem involved. Sensitivity analysis can for example be used to provide information as part of an uncertainty analysis to determine best estimate plus uncertainty results to the required confidence level. In order to address uncertainty propagation in analysis and methods in the HTGR community the IAEA initiated a Coordinated Research Project (CRP) on the HTGR Uncertainty Analysis in Modelling (UAM) that officially started in 2013. Although this project focuses specifically on the peculiarities of HTGR designs and its simulation requirements, many lessons can be learned from the LWR community and the significant progress already made towards a consistent methodology uncertainty analysis. In the case of LWRs the NRC has already in 1988 amended 10 CFR 50.46 to allow best-estimate (plus uncertainties) calculations of emergency core cooling system performance. The Nuclear Energy Agency (NEA) of the Organization for Economic Co-operation and Development (OECD) also established an Expert Group on "Uncertainty Analysis in Modelling" which finally led to the definition of the "Benchmark for Uncertainty Analysis in Modelling (UAM) for Design, Operation and Safety Analysis of LWRs". The CRP on HTGR UAM will follow as far as possible the on-going OECD Light Water Reactor UAM benchmark activity.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗
DOE OSTI2018

Versatile Surface Functionalization of Metal-Organic Frameworks through Direct Metal Coordination with a Phenolic Lipid Enables Diverse Applications

A novel strategy for the versatile functionalization of the external surface of metal-organic frameworks (MOFs) has been developed based on the direct coordination of a phenolic-inspired lipid molecule DPGG (1,2-dipalmitoyl-sn-glycero-3-galloyl) with metal nodes/sites surrounding MOF surface. X-ray diffraction and Argon sorption analysis prove that the modified MOF particles retain their structural integrity and porosity after surface modification. Density functional theory calculations reveal that strong chelation strength between the metal sites and the galloyl head group of DPGG is the basic prerequisite for successful coating. Due to the pH-responsive nature of metal-phenol complexation, the modification process is reversible by simple washing in weak acidic water, showing an excellent regeneration ability for water-stable MOFs. Moreover, the colloidal stability of the modified MOFs in the nonpolar solvent allows them to be further organized into 2 dimensional MOF or MOF/polymer monolayers by evaporation-induced interfacial assembly conducted on an air/water interface. Lastly, the easy fusion of a second functional layer onto DPGG-modified MOF cores, enabled a series of MOF-based functional nanoarchitectures, such as MOFs encapsulated within hybrid supported lipid bilayers (so-called protocells), polyhedral core-shell structures, hybrid lipid-modified-plasmonic vesicles and multicomponent supraparticles with target functionalities, to be generated. for a wide range of applications.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Semiconducting to Metallic Electronic Landscapes in Defects-Controlled 2D π-d Conjugated Coordination Polymer Thin Films

Two-dimensional coordination polymers (2DCPs) have been predicted to exhibit exotic properties such as superconductivity, topological insulating behavior, catalytic activity, and superior ion transport for energy applications; experimentally, these materials have fallen short of their expectation due to the lack of synthesis protocols that yield continuous, large crystallite domains, and highly ordered thin films with controllable physical and chemical properties. Herein, the fabrication of large-area, highly ordered 2DCP thin films with large crystallite domains using chemical vapor deposition (CVD) approaches is described. It is demonstrated that defects and the packing motifs of 2DCP thin films may be controlled by adjusting the vapor–vapor and vapor–solid interactions of the metal and organic linker precursors during the CVD fabrication process. Such control allows for the fabrication of defects-controlled 2DCP thin films that show either semiconducting or metallic behavior. The findings provide the first demonstration of tuning the electrical properties of sub 100 nm-thick continuous 2DCP thin films by controlling their electronic landscape through defect engineering. As such, it is determined that large-area, highly ordered 2DCP thin films may undergo a semiconducting to metallic transition that is correlated to changes in morphology, crystalline domain sizes, crystallite orientation, defect interactions, and electronic structure.

2D coordination polymers↗