IEEE 123-Bus System A Matrix
System component matrix for IEEE 123 bus distribution system for dynamic simulations.
Sahu, Vibhuti [Oak Ridge National Laboratory] (ORC↗
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Results for “EMT”
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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IEEE39_IBL_Dataset
IEEE39 with IBL modified system EMT dataset.
Madurasinghe, Dulip [ORNL] (ORCID:0000000249316597↗
RE-INTEGRATE: Type-3 Wind Turbine Generator Model
Model developed for Type-3 Wind Turbine Generators in EMT Simulator REINTEGRATE
Sahu, Vibhuti [ORNL] (ORCID:000000034808527X)↗
ZEB1 insufficiency causes corneal endothelial cell state transition and altered cellular processing
The zinc finger e-box binding homeobox 1 (ZEB1) transcription factor is a master regulator of the epithelial to mesenchymal transition (EMT), and of the reverse mesenchymal to epithelial transition (MET) processes. ZEB1 plays an integral role in mediating cell state transitions during cell lineage specification, wound healing and disease. EMT/MET are characterized by distinct changes in molecular and cellular phenotype that are generally context-independent. Posterior polymorphous corneal dystrophy (PPCD), associated with ZEB1 insufficiency, provides a new biological context in which to understand and evaluate the classic EMT/MET paradigm. PPCD is characterized by a cadherin-switch and transition to an epithelial-like transcriptomic and cellular phenotype, which we study in a cell-based model of PPCD generated using CRISPR-Cas9-mediated ZEB1 knockout in corneal endothelial cells (CEnCs). Transcriptomic and functional studies support the hypothesis that CEnC undergo a MET-like transition in PPCD, termed endothelial to epithelial transition (EnET), and lead to the conclusion that EnET may be considered a corollary to the classic EMT/MET paradigm.
59 BASIC BIOLOGICAL SCIENCES↗
FAM83D promotes cell proliferation and motility by downregulating tumor suppressor gene FBXW7
Amplification of chromosome 20q is frequently found in various types of human cancers, including breast cancer. The list of candidate oncogenes in 20q has expanded over the past decade. Here, we investigate whether FAM83D (family with sequence similarity 83, member D) on chromosome 20q plays any role in breast cancer development. The expression level of FAM83D is significantly elevated in breast cancer cell lines and primary human breast cancers. High expression levels of FAM83D are significantly associated with poor clinical outcome and distant metastasis in breast cancer patients. We show that ectopic expression of FAM83D in human mammary epithelial cells promotes cell proliferation, migration and invasion along with epithelial-mesenchymal transition (EMT). Ablation of FAM83D in breast cancer cells induces apoptosis and consequently inhibits cell proliferation and colony formation. Mechanistic studies reveal that overexpression of FAM83D downregulates FBXW7 expression levels through a physical interaction, which results in elevated protein levels of oncogenic substrates downstream to FBXW7, such as mTOR, whose inhibition by rapamycin can suppress FAM83D-induced cell migration and invasion. The results demonstrate that FAM83D has prognostic value for breast cancer patients and is a novel oncogene in breast cancer development that at least in part acts through mTOR hyper-activation by inhibiting FBXW7.
59 BASIC BIOLOGICAL SCIENCES↗
Analysis of Benefits of an Energy Imbalance Market in the NWPP
The Northwest Power Pool (NWPP) Market Assessment Committee (MC) Initiative, which was officially launched on March 19, 2012, set out to explore a range of alternatives that could help the Balancing Authorities and scheduling utilities in the NWPP area address growing operational and commercial challenges affecting the regional power system. The MC formed an Analytical Team with technical representatives from each of the member Balancing Areas in the NWPP and with staff of Pacific Northwest National Laboratory (PNNL). This Analytical Team was instructed to conduct extensive studies of intra-hour operation of the NWPP system in the year 2020 and of the NWPP region with 14,671 MW of wind penetration. The effort utilized a sub-hourly production cost model (the PLEXOS® computer model) that inputs data from the Western Electricity Coordinating Council (WECC)-wide Production Cost Model (PCM) to evaluate potential production cost savings. The Analytical Team was given two general options to evaluate: •Energy Imbalance Market (EIM): establishment of an automated, organized NWPP area market for economically supplying energy imbalance within the hour. •Enhanced Market-Operational Tools (EMT) that might augment or replace an EIM. The Analytical The Analytical Team built on the WECC-wide PCM data from prior work done in the WECC and carried forward the evolution of the original WECC Transmission Expansion Planning Policy Committee (TEPPC) 2020 PC0 data base. A large number of modifications and improvements were made to this case and the data were subjected to extensive review by the team members to improve the model representation of the Northwest (NW). MC meetings that were open to the public were held for interested parties to review and provide input to the study. Results for the test, base, and sensitivity case studies performed by the MC Initiative Analytical Team indicate that there are a wide range of benefits that could be obtained from the operation of an EIM in the NWPP depending on what assumptions are made. The instructions from the MC were to determine a "minimum high confidence" range of potential benefits. The results for the Base Case indicate that the EIM benefits ranged from approximately $40 million to $70 million in annual savings from the operation of an EIM in the NWPP footprint. A number of additional relevant sensitivity cases were performed, including low and high water conditions, low and high natural gas prices, and various flex reserve requirements, resource operations, and amounts of resource capability held back during the preschedule period. Along with the results for the Base Case, the results for these studies yielded EIM benefits that clustered within the range of $70 to $80 million dollars per year with potential benefits ranging from approximately $125 million to as little as $17 million per year. Because the design and operation of an EIM could enable participating Balancing Authorities (BAs) to collectively lower the quantity of resources they must carry to meet within-hour balancing needs, a sensitivity case was also performed to analyze the impact that such reductions might have on the benefits from an EIM. The results for this sensitivity case indicate that such reductions could increase the benefits from the operation of an EIM in the NWPP into the range of approximately $130 million to $160 million per year. Also, a sensitivity case for a WECC-wide EIM was performed with the results indicating that the potential benefits to the NWPP could increase into the range of $197 million to $233 million per year. While there may be potential reliability benefits from the coordinated dispatch process underlying the operation of an EIM, reliability benefits from an EIM were out of the scope of this study. The EIM benefit analyses that were performed by the Analytical Team are provided in this report.
Power markets, NWPP, Energy Imbalance, EIM, Renewa↗
Assessing Inverter-Based Resources Modeling Gaps in Commonly Used Short-Circuit Programs
Future bulk power systems are expected to operate with a high penetration of inverter-based resources (IBR). This is anticipated to fundamentally change the system’s short-circuit behaviors and demand a change in existing transmission line protection settings or schemes. Phasor-domain short circuit programs (e.g., ASPEN, CAPE, and CYME) remain the mainstream tools for developing protection settings. However, the system protection community has shared concerns about the accuracy of IBR models in short-circuit programs. This report compares the performance of existing generic IBR models in short-circuit programs with detailed electro-magnetic transient (EMT) models provided by several different IBR manufacturers in PSCAD, to quantify the short-circuit program’s IBR model accuracy, assess their ability to replicate individual IBR controls such as negative sequence current injections, and identify specific gaps in the existing generic phasor-domain IBR models that are currently available.
42 ENGINEERING↗
Modeling Framework for Data Center
This chapter highlights the critical need for advanced modeling of data centers due to their rapidly increasing energy consumption and impact on grid reliability. Driven by the demand for AI applications, data centers are projected to consume a significant portion of US energy by 2028, putting stress on an already challenged power grid. The chapter emphasizes the importance of "fast" time-scale models to understand the dynamic interactions between data centers and the grid, especially given the rapid power fluctuations of AI workloads. It outlines a modeling framework that includes both offline and real-time EMT domain simulations, detailing the necessary representations for various components like utility interfaces, transformers, IT loads, UPS, cooling loads, Battery Energy Storage Systems (BESS), generators, protection systems, and higher-level control systems. While standard simulation tools like PSCAD offer basic models, custom development is often required to accurately capture the unique and fast-changing behaviors of modern data centers. The chapter also discusses key metrics and test cases for validating these models, focusing on transient load responses, protection relay coordination, and demand flexibility. Finally, it addresses the challenges of modeling large-scale data centers, such as computational complexity and the trade-off between model fidelity and practicality, suggesting hybrid modeling approaches as a solution. The overarching goal is to create a robust framework that helps assess data center impacts on grid stability, identify vulnerabilities, and inform the development of standards for reliable integration of these large loads into the bulk power system.
25 ENERGY STORAGE↗
Two-Way Coupled CFD/DEM Simulation of Electromagnetic Heating in a Fluidized Bed Reactor
A set of tools has been developed to couple a multiphase reacting computational fluid dynamics solver (MFIX) with two computational electromagnetic solvers (COMSOL and Elmer). In contrast to several recent investigations, which calculate a single static EM field prior to the CFD calculation, in the present work the electromagnetic field is periodically updated during the simulation. This enables the EM field and associated EM heating predictions to reflect the effects of evolving material properties (temperature, composition, size etc.) and the evolving distribution of material in the system. The present work uses effective medium theory (EMT) for the electromagnetic field calculations since the goal is to apply the tool for industrial scale reacting systems. Predictions using MFIX/COMSOL and MFIX/Elmer are compared to in bed thermocouple measurements from a fluidized bed experiment and recent simulation predictions and recent experiments performed at NETL. The NETL experiments also include packed bed operating conditions. Coupled MFIX/COMSOL simulations at these conditions are compared with similar simulations using only COMSOL to measure errors due to the solver coupling approach.
CFD↗
Loss of Cadherin-11 in pancreatic ductal adenocarcinoma alters tumor-immune microenvironment
Pancreatic ductal adenocarcinoma (PDAC) is one of the top five deadliest forms of cancer with very few treatment options. The 5-year survival rate for PDAC is 10% following diagnosis. Cadherin 11 (Cdh11), a cell-to-cell adhesion molecule, has been suggested to promote tumor growth and immunosuppression in PDAC, and Cdh11 inhibition significantly extended survival in mice with PDAC. However, the mechanisms by which Cdh11 deficiency influences PDAC progression and anti-tumor immune responses have yet to be fully elucidated. To investigate Cdh11-deficiency induced changes in PDAC tumor microenvironment (TME), we crossed p48-Cre; LSL-Kras G12D/+ ; LSLTrp53 R172H/+ (KPC) mice with Cdh11 +/- mice and performed single-cell RNA sequencing (scRNA-seq) of the non-immune (CD45 - ) and immune (CD45 + ) compartment of KPC tumor-bearing Cdh11 proficient (KPC-Cdh11 +/+ ) and Cdh11 deficient (KPC-Cdh11 +/- ) mice. Our analysis showed that Cdh11 is expressed primarily in cancer-associated fibroblasts (CAFs) and at low levels in epithelial cells undergoing epithelial-to-mesenchymal transition (EMT). Cdh11 deficiency altered the molecular profile of CAFs, leading to a decrease in the expression of myofibroblast markers such as Acta2 and Tagln and cytokines such as Il6, Il33 and Midkine (Mdk). We also observed a significant decrease in the presence of monocytes/macrophages and neutrophils in KPC-Cdh11 +/- tumors while the proportion of T cells was increased. Additionally, myeloid lineage cells from Cdh11-deficient tumors had reduced expression of immunosuppressive cytokines that have previously been shown to play a role in immune suppression. In summary, our data suggests that Cdh11 deficiency significantly alters the fibroblast and immune microenvironments and contributes to the reduction of immunosuppressive cytokines, leading to an increase in anti-tumor immunity and enhanced survival.
59 BASIC BIOLOGICAL SCIENCES↗
A Systematic Framework for Tuning Open-Source Multifunctional IBR Models To Emulate OEM Black-Box Fault Dynamics
This paper presents a systematic framework to tune a generic IBR EMT model to match with an OEM provided balckbox inverter model based on the fault current responses. The key learnings and findings are summarized as follows: The tunable key parameters include inner control loops and current limiters to align the fault current magnitude, sequence content, and phase trajectories with the OEM models across diverse fault type and locations. The tuned model's fidelity is validated through comparative analysis with an OEM blackbox model, assessing both the fault current response and the responses of multiple relay elements. The results demonstrate the tuned generic model can trigger relay decision logic that is identical or near identical to that of the OEM model, thus generating very good match model for fault studies.
24 POWER TRANSMISSION AND DISTRIBUTION↗
Evaluation of a Reduced-Order Model for IBR Fault Response Representation via OEM Blackbox Models
This paper presents a fully implemented inverter reduced-order-model (ROM) in an EMT simulation (PSCAD) library component for direct user utilization in protection studies. The developed inverter ROM has the following features: Equivalent to a full inverter-based resource (IBR) inverter model with positive- and negative-sequence current formulation and representation. A Python script is developed to fully automate this process, including training data generation, ROM parameter training, updating parameters, and model verification and validation. The ROM is validated using both IEEE 2800-compliant and non-compliant OEM modes in a real-world system, building confidence of its usability by protection engineers.
24 POWER TRANSMISSION AND DISTRIBUTION↗
Control logic for a 30 cm diameter ion thruster
Tests with a 30 cm thruster having EMT critical components have defined start-up criteria. Of the three phases comprising the start-up mode, the preheat phase is intended to heat critical feed system components to desired temperatures. Of the seven supplies available during the preheat phase, only three were found to be useful for purposes of preheating the thruster. These were the cathode and neutralizer tip heater supplies and the isolator heater supply. If the needed temperatures are attained during preheat, the ignition phase requires only several seconds. The heat phase serves to establish the proper propellant flow rates prior to the transition to the run mode. Using these techniques, a thruster with initial temperatures in the range of -15 to +25 C can be reliably started and provide a 1.0 amp beam within 45 min. High voltage recycle time profiles indicate limitations on several time functions.
Bechtel, R. T.↗
Emergency medical services
When NASA was established in 1958, it was known that space flight would require efforts beyond those of NASA to ensure the health and safety of our astronauts. On 10 Aug. 1958, a Secretary of Defense memorandum was signed that assigned the first Department of Defense (DOD) Manager to provide support to NASA for Project Mercury. This established a chain of command through the Joint Chiefs of Staff to the Secretary of Defense. The current charter is dated 19 Mar. 1986 and assigns the DOD Manager responsibilities to the Commander and Chief, US Space Command. The DOD Managers charter has many support areas and among them are recovery of astronauts and medical support. Today these efforts support the Space Shuttle and Space Station Programs. Briefly, the program works with each organization tasking the other through a requirements document. Level of care, communications, and recovery requirements are established; NASA and the DOD provide the capability to meet them. NASA is also responsible for the specialized training and equipment needed to meet these requirements. A Shuttle launch a KSC requires an Emergency Medical Services (EMS) coordinator on console to facilitate communications, ensure proper coverage, and coordinate with area hospitals. A contingent of NASA medical personnel are assembled to provide triage and medical support capabilities. The DOD provides medical evacuation (MEDEVAC) helicopters with surgeons and pararescue specialists (PJ's) or emergency medical technicians (EMT's). Each helicopter is equipped with at least one doctor and one PJ/EMT per astronaut crew member. Transoceanic abort landing (TAL) sites and end of mission (EOM) sites have similar structures, with TAL sites utilizing fixed wingg aircraft for MEDEVAC. The DOD also supports contingency planning for the support and return of crew members from the Space Station Freedom. Much of this support has been directed at the recovery of crew members following the landing of an Assured Crew Return Vehicle.
Billica, Roger↗
NSTAR Ion Propulsion System Power Electronics
The NASA Solar Electric Propulsion Technology Application Readiness (NSTAR) program, managed by the Jet Propulsion Laboratory (JPL), is currently developing a high performance, simplified ion propulsion system. This propulsion system, which is throttleable from 0.5- to 2.3-kW output power to the thruster, targets primary propulsion applications for planetary and Earth-space missions and has been baselined as the primary propulsion system for the first New Millennium spacecraft. The NASA Lewis Research Center is responsible for the design and delivery of a breadboard power processing unit (PPU) and an engineering model thruster (EMT) for this system and will manage the contract for the delivery of the flight hardware to JPL. The PPU requirements, which dictate a mass of less than 12 kg with an efficiency of 0.9 or greater at a 2.3-kW output, forced a departure from the state-of-the-art ion thruster PPU design. Several innovations--including dual-use topologies, simplified thruster control, and the use of ferrite magnetic materials--were necessary to meet these requirements.
Source record↗
Preliminary Spectroscopic Measurements for a Gallium Electromagnetic (GEM) Thruster
As a propellant option for electromagnetic thrusters, liquid ,gallium appears to have several advantages relative to other propellants. The merits of using gallium in an electromagnetic thruster (EMT) are discussed and estimates of discharge current levels and mass flow rates yielding efficient operation are given. The gallium atomic weight of 70 predicts high efficiency in the 1500-2000 s specific impulse range, making it ideal for higher-thrust, near-Earth missions. A spatially and temporally broad spectroscopic survey in the 220-520 nm range is used to determine which species are present in the plasma and estimate electron temperature. The spectra show that neutral, singly, and doubly ionized gallium species are present in a 20 J, 1.8 kA (peak) are discharge. With graphite present on the insulator to facilitate breakdown, singly and doubly ionized carbon atoms are also present, and emission is observed from molecular carbon (CZ) radicals. A determination of the electron temperature was attempted using relative emission line data, and while the spatially and temporally averaged, spectra don't fit well to single temperatures, the data and presence of doubly ionized gallium are consistent with distributions in the 1-3 eV range.
Thomas, Robert E.↗
Impedance Characterization of Utility-Scale Renewable Energy and Storage Systems: Preprint
This paper presents the impedance characterization of utility-scale wind turbines and PV/storage inverters using a multimegawatt grid simulator-based grid integration testbed. The paper describes testbed components including a 7 MVA grid simulator, 5 MW dynamometer, medium-voltage measurement system, and real-time control system used for automated impedance characterization of wind turbines and inverters. Different aspects of impedance measurement are discussed, including the selection of the magnitude and type of perturbation, measurement of frequency cross-coupling between sequence impedance responses, and the alignment of the reference frame for sequence impedance measurement. The paper also demonstrates high-fidelity validation of EMT simulation models and characterization of grid-forming inverters using impedance measurements.
17 WIND ENERGY↗
Impedance Measurement of Wind Turbines using a Multimegawatt Grid Simulator: Preprint
This paper presents the impedance measurements of a 4 MW wind turbine conducted using a multimegawatt grid simulator at the National Renewable Energy Laboratory in Colorado, United States. This paper describes different systems, including a 7 MVA grid simulator, a 5 MW dynamometer, a medium-voltage measurement system, and a real-time control system used for the automated impedance measurement of a utility-scale wind turbine. Different aspects of impedance measurement are discussed, including the selection of the magnitude of injected perturbation, measurement of frequency cross-coupling between the sequence impedance responses, and the alignment of the reference frame for sequence impedance measurement. The paper also demonstrates high-fidelity validation of an EMT simulation model of the wind turbine using impedance measurements.
24 POWER TRANSMISSION AND DISTRIBUTION↗