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Results for “Utility Regulation”

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 559 records · Page 31
All sourcesNASA NTRSDOE OSTI
NASA NTRS1982

A 400-kWe high-efficiency steam turbine for industrial cogeneration

An advanced state-of-the-art steam turbine-generator developed to serve as the power conversion subsystem for the Department of Energy's Sandia National Laboratories' Solar Total-Energy Project (STEP) is described. The turbine-generator, which is designed to provide 400-kW of net electrical power, represents the largest turbine-generator built specifically for commercial solar-powered cogeneration. The controls for the turbine-generator incorporate a multiple, partial-arc entry to provide efficient off-design performance, as well as an extraction control scheme to permit extraction flow regulation while maintaining 110-spsig pressure. Normal turbine operation is achieved while synchronized to a local utility and in a stand-alone mode. In both cases, the turbine-generator features automatic load control as well as remote start-up and shutdown capability. Tests totaling 200 hours were conducted to confirm the integrity of the turbine's mechanical structure and control function. Performance tests resulted in a measured inlet throttle flow of 8,450 pounds per hour, which was near design conditions.

Leibowitz, H. M.↗
NASA NTRS2008

Small Autonomous Aircraft Servo Health Monitoring

Small air vehicles offer challenging power, weight, and volume constraints when considering implementation of system health monitoring technologies. In order to develop a testbed for monitoring the health and integrity of control surface servos and linkages, the Autonomous Aircraft Servo Health Monitoring system has been designed for small Uninhabited Aerial Vehicle (UAV) platforms to detect problematic behavior from servos and the air craft structures they control, This system will serve to verify the structural integrity of an aircraft's servos and linkages and thereby, through early detection of a problematic situation, minimize the chances of an aircraft accident. Embry-Riddle Aeronautical University's rotary-winged UAV has an Airborne Power management unit that is responsible for regulating, distributing, and monitoring the power supplied to the UAV's avionics. The current sensing technology utilized by the Airborne Power Management system is also the basis for the Servo Health system. The Servo Health system measures the current draw of the servos while the servos are in Motion in order to quantify the servo health. During a preflight check, deviations from a known baseline behavior can be logged and their causes found upon closer inspection of the aircraft. The erratic behavior nay include binding as a result of dirt buildup or backlash caused by looseness in the mechanical linkages. Moreover, the Servo Health system will allow elusive problems to be identified and preventative measures taken to avoid unnecessary hazardous conditions in small autonomous aircraft.

Quintero, Steven↗
DOE OSTI2021

Mass spectrometry-based proteomics for analysis of hydrophilic phosphopeptides

Protein phosphorylation is a critical post-translational modification (PTM), with cell signaling networks being tightly regulated by protein phosphorylation. Despite recent technological advances in reversed-phase liquid chromatography (RPLC)-mass spectrometry (MS)-based proteomics, comprehensive phosphoproteomic coverage in complex biological systems remains challenging, especially for hydrophilic phosphopeptides that often have multiple phosphorylation sites. Herein we describe an MS-based phosphoproteomics protocol for effective quantitative analysis of hydrophilic phosphopeptides. This protocol was built upon a simple tandem mass tag (TMT)-labeling method for significantly increasing peptide hydrophobicity, thus effectively enhancing RPLC-MS analysis of hydrophilic peptides. Through phosphoproteomic analyses of MCF7 cells, this method was demonstrated to greatly increase the number of identified hydrophilic phosphopeptides and improve MS signal detection. With the TMT labeling method, we were able to identify a previously unreported phosphopeptide from the G protein-coupled receptor (GPCR) CXCR3, QPpSSSR, which is thought to be important in regulating receptor signaling. This protocol is easy to adopt and implement, and thus should have broad utility for effective RPLC-MS analysis of the hydrophilic phosphoproteome as well as other highly hydrophilic analytes.

Hydrophilic phosphopeptide, Phosphoproteomics, TMT↗
DOE OSTI2019

Radon Considerations at Environmental Remediation Sites - 19469

Radon and how it is regulated poses many challenges to the U.S. Army Corps of Engineers (USACE) in executing the Formerly Utilized Sites Remedial Action Program (FUSRAP). These challenges include:, terminology; radon measurement methods and limitations; state certification and testing requirements; limited and potentially conflicting federal guidance; background considerations; and limited experience regarding application of guidance; among others. These challenges and others are discussed in detail. The FUSRAP Maywood Superfund Site (FMSS) is presented as a case study demonstrating these challenges and considerations to mitigate or address the challenges. The USACE, U.S. Environmental Protection Agency (USEPA), and the New Jersey Department of Environmental Protection (NJDEP) (NJDEP) have spent several years working on and continue to work through the radon issues at FMSS. The FMSS experience, information, and solutions presented in this paper will be helpful to other environmental sites with radium and thorium contamination. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2023

The Effect of Prosumer Duality on Power Market: The Effect of Market Regulation

Electricity prosumers are energy subsystems that not only consume, but also produce electricity. They are present in distribution level networks as traditional utility customers who have installed distributed energy resources. They are also present in transmission level networks as large conglomerates own both generation assets and large industrial loads. Previous work on the economics of prosumers has demonstrated that prosumers in a market have incentives to behave more competitively compared to producers and consumers in traditional markets. This paper further explores the behavior of prosumers and their response to market policies including the allocation of network losses and the impact of net metering. We extend a Cournot model of a dual prosumer and find that prosumers respond with higher supply quantities if network losses are allocated to demand base. They respond with lower supply quantities if network losses are allocated to supply base. Allocating network losses to demand base also causes equilibrium prices to decline. Markets where prosumers first satisfy their own load and then sell the balance of electricity to the grid have lower quantities and higher prices compared to markets where prosumers buy and sell at locational marginal price.

Tsybina, Eve↗
DOE OSTI2024

Multi-agent voltage control in distribution systems using GAN-DRL-based approach

Active distribution grids can experience voltage fluctuations and violations due to the high penetration of variable distributed energy resources (DERs). These problems might occur because of the uncertain and variable generation natures of these resources, especially solar photovoltaic resources, during panel shadowing scenarios. Volt-VAR control (VVC) is an efficient method that controls the reactive power set-points of the inverters to regulate the voltage of distribution grids. Although several VVC approaches have been proposed recently, the performance of these approaches degrades significantly if behind-the-meter solar generation data are unobservable/missing. Therefore, it is necessary to impute missing/unobservable PV data accurately to be utilized in VVC approaches. Further, this paper proposes a model-free, data-driven, centrally trained, and decentrally executed multi-agent deep reinforcement learning-based VVC architecture to regulate the voltage of distribution networks. A generative adversarial network (GAN) is incorporated to impute the unobservable PV data accurately, which improves the performance of the proposed control architecture. The proposed multi-agent-soft-actor–critic algorithm (MASAC)-based VVC technique utilizes the actual PV dataset as well as the imputed dataset from the GAN framework to learn the optimal coordinated control policy for controlling the optimal reactive power set-points of PV inverters. The effectiveness of the proposed approach is analyzed on a modified IEEE 34-bus test case with added PV inverters. The results are compared and analyzed with a base case model with no VVC and VVC with a local droop control approach, genetic algorithm optimization, and a centralized soft actor–critic-based approach. Moreover, the performance of the proposed approach is compared with that of a multi-agent VVC framework without using the PV generation data and load information as the system state. The results illustrate that the proposed method with more state input improves the voltage profile and reduces the power loss of the network across various loading and PV generation scenarios.

14 SOLAR ENERGY↗
DOE OSTI2020

Machine learning uncovers independently regulated modules in the Bacillus subtilis transcriptome

The transcriptional regulatory network (TRN) of Bacillus subtilis coordinates cellular functions of fundamental interest, including metabolism, biofilm formation, and sporulation. Here, we use unsupervised machine learning to modularize the transcriptome and quantitatively describe regulatory activity under diverse conditions, creating an unbiased summary of gene expression. We obtain 83 independently modulated gene sets that explain most of the variance in expression and demonstrate that 76% of them represent the effects of known regulators. The TRN structure and its condition-dependent activity uncover putative or recently discovered roles for at least five regulons, such as a relationship between histidine utilization and quorum sensing. The TRN also facilitates quantification of population-level sporulation states. As this TRN covers the majority of the transcriptome and concisely characterizes the global expression state, it could inform research on nearly every aspect of transcriptional regulation in B. subtilis.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRSDate not supplied

Neurovascular effects of simulated space radiation

A major health risk for human deep space exploration is central nervous system (CNS) damage by ionizing radiation. Simulated galactic cosmic rays or their components, especially high-linear energy transfer particles such as 56Fe ions, have been shown to cause CNS damage, neuroinflammation and cognitive dysfunction in rodent models, but their effects on human CNS remain to be investigated. CNS damage from any insult, including ionizing radiation, is partially mediated by the blood-brain barrier (BBB), which regulates interactions between CNS and the rest of the body. Astrocytes are major cellular regulators of BBB permeability and also modulate neuroinflammation and neurodegeneration. However, BBB and astrocyte functions in regulating CNS responses to space radiation remain little investigated, especially in human organ analogs. Therefore, we developed and utilized a high-throughput 3D human neurovascular organ-on-a-chip model, seeded with induced pluripotent stem cell-derived cells. The effects of time course, ionizing radiation dose and dose rate were mapped by exposing the model to either acute, high dose rate radiation with simulated galactic cosmic rays or 600 MeV/n 56Fe particles, or protracted, low dose rate gamma radiation using a 57Co sealed source setup. We investigated BBB permeability, oxidative stress, cellular damage and secreted factors over the time period between 24 hours – 2 weeks after 0.1 – 0.8 Gy irradiation. We observed that ionizing radiation exposure increased BBB permeability, caused oxidative stress, damaged endothelial cells and altered expression of inflammatory cytokines with a subset of outcomes dependent on ionizing radiation dose rate. Furthermore, our results indicated that astrocyte functions were primarily deleterious at early time points and protective later after irradiation, resembling CNS responses to injury in vivo. Our findings in organ models were complemented by studies on true spaceflight using mouse spatial and single cell multi-omics, which similarly indicated spaceflight-mediated changes in astrocyte functions. In summary, our study evaluates the regulation of neurovascular responses to simulated space radiation, suggesting astrocytes as targets for countermeasures to mitigate CNS damage in deep space exploration.

Radiation↗
DOE OSTI2017

Structural and Functional Characterization of a Short-Chain Flavodoxin Associated with a Noncanonical 1,2-Propanediol Utilization Bacterial Microcompartment

Bacterial microcompartments (BMCs) are proteinaceous organelles that encapsulate enzymes involved in CO 2 fixation (carboxysomes). or carbon catabolism (metabolosomes). Metabolosomes share a common core of enzymes and a distinct signature enzyme for substrate degradation that defines the function of the BMC (e,g., propanediol or ethanolamine utilization BMCs, or glycyl-radical enzyme microcompartments). Loci encoding metabolosomes also typically contain genes for proteins that support organelle function, such as regulation, transport of substrate, and cofactor (e.g., vitamin B-12) synthesis and recycling. Flavoproteins are frequently among these ancillary gene products, suggesting that these redox active proteins play an undetermined function in many metabolosomes. Here in this paper, we report the first characterization of a BMC-associated flavodoxin (Fld1C), a small flavoprotein, derived from the noncanonical 1,2-propanediol utilization BMC locus (PDU1C) of Lactobacillus reuteri. The 2.0 angstrom X-ray structure of Fld1C displays the alpha/beta flavodoxin fold, which noncovalently binds a single flavin mononucleotide molecule. Fld1C is a short-chain flavodoxin with redox potentials of -240 +/- 3 mV oxidized/semiquinone and -344 +/- 1 mV semiquinone/hydroquinone versus the standard hydrogen electrode at pH 7.5. It can participate in an electron transfer reaction with a photoreductant to form a stable semiquinone species. Collectively, our structural and functional results suggest that PDU1C BMCs encapsulate Fld1C to store and transfer electrons for the reactivation and/or recycling of the B 12 cofactor utilized by the signature enzyme.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2023

Engineering transcriptional regulation of pentose metabolism in Rhodosporidium toruloides for improved conversion of xylose to bioproducts

Abstract Efficient conversion of pentose sugars remains a significant barrier to the replacement of petroleum-derived chemicals with plant biomass-derived bioproducts. While the oleaginous yeast Rhodosporidium toruloides (also known as Rhodotorula toruloides ) has a relatively robust native metabolism of pentose sugars compared to other wild yeasts, faster assimilation of those sugars will be required for industrial utilization of pentoses. To increase the rate of pentose assimilation in R. toruloides, we leveraged previously reported high-throughput fitness data to identify potential regulators of pentose catabolism. Two genes were selected for further investigation, a putative transcription factor (RTO4_12978, Pnt1) and a homolog of a glucose transceptor involved in carbon catabolite repression (RTO4_11990). Overexpression of Pnt1 increased the specific growth rate approximately twofold early in cultures on xylose and increased the maximum specific growth by 18% while decreasing accumulation of arabitol and xylitol in fast-growing cultures. Improved growth dynamics on xylose translated to a 120% increase in the overall rate of xylose conversion to fatty alcohols in batch culture. Proteomic analysis confirmed that Pnt1 is a major regulator of pentose catabolism in R. toruloides. Deletion of RTO4_11990 increased the growth rate on xylose, but did not relieve carbon catabolite repression in the presence of glucose. Carbon catabolite repression signaling networks remain poorly characterized in R. toruloides and likely comprise a different set of proteins than those mainly characterized in ascomycete fungi.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2021

Endothelial cells control vascular smooth muscle cell cholesterol levels by regulating 24-dehydrocholesterol reductase expression

Highlights: • Suspended endothelial and vascular smooth muscle cells organize to form spherical vascular organoids in hanging drops. • Vascular smooth muscle cells downregulate the expression of metabolism regulating genes in presence of endothelial cells. • Endothelial cells decrease the levels of 24-dehydrocholesterol reductase and cholesterol in vascular smooth muscle cells. • Diminished cholesterol biosynthesis inhibits vascular smooth muscle cell activity. Communication of vascular cells is essential for the control of organotypic functions of blood vessels. In this context, vascular endothelial cells (EC) act as potent regulators of vascular smooth muscle cell (VSMC) functions such as contraction and relaxation. However, the impact of ECs on the gene expression pattern of VSMCs is largely unknown. Here, we investigated changes of the VSMC transcriptome by utilizing 3D human vascular organoids organized as a core of VSMCs enclosed by a monolayer of ECs. Microarray-based analyses indicated that interaction with ECs for 48 h down-regulates expression of genes in VSMCs controlling rate-limiting steps of the cholesterol biosynthesis such as HMGCR, HMGCS1, DHCR24 and DHCR7. Protein analyses revealed a decrease in the abundance of DHCR24 (24-dehydrocholesterol reductase) and lower cholesterol levels in VSMCs co-cultured with ECs. On the functional level, the blockade of the DHCR24 activity impaired adhesion, migration and proliferation of VSMCs. Collectively, these findings indicate that ECs have the capacity to instruct VSMCs to shut down the expression of DHCR24 thereby limiting their cholesterol biosynthesis, which may support their functional steady state.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2020

CamRegBase: a gene regulation database for the biofuel crop, Camelina sativa

Abstract Camelina is an annual oilseed plant from the Brassicaceae family that is gaining momentum as a biofuel winter cover crop. However, a significant limitation in further enhancing its utility as a producer of oils that can be used as biofuels, jet fuels or bio-based products is the absence of a repository for all the gene expression and regulatory information that is being rapidly generated by the community. Here, we provide CamRegBase (https://camregbase.org/) as a one-stop resource to access Camelina information on gene expression and co-expression, transcription factors, lipid associated genes and genome-wide orthologs in the close-relative reference plant Arabidopsis. We envision this as a resource of curated information for users, as well as a repository of new gene regulation information.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2017

EliteTree™: an advanced biomass tree crop technology that features greater wood density and accelerated stem growth

Due to wood's potential for large-scale commercial production of biofuels, a rapid increase in the use of wood as a source of energy is anticipated as policies promoting greater use of renewable energy are adopted globally. However, the economics of purpose-grown tree feedstocks for energy show that these production systems are not financially viable without improvement in the base growth rate. Conventional breeding programs have produced willow and poplar clones that show potential for rapid growth, but current top-performing clones do not grow fast enough for profitable biofuel production. Genetic manipulation of secondary wall biosynthesis is the most direct path to resolving this growth barrier. To that end, we developed an innovative biomass tree crop technology, EliteTree™, that results in greater wood density and accelerated growth of stems. This technology is built on overexpression of Gibberellin 20-oxidase to increase plant stem growth in both height and diameter and increase lignocellulosic biomass accumulation through overexpression of the transcription factor MYB46, which is a master regulator for secondary wall biosynthesis. EliteTree™ technology uses 2A-mediated bicistronic gene expression, with our proprietary utility promoter DX15, such that the genetic manipulation is limited to wood tissue, yielding transgenic poplars with xylem-specific co-expression of MYB46 and PdGA20ox1. The development of faster growing elite tree genotypes with increased wood density and growth rates will pave the way for truly sustainable and economically viable bioenergy/biofuel production using short rotation tree plantations, and ultimately will lessen carbon emissions and has the potential to revitalize rural economies.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2019

Development of high efficiency window air conditioner using propane under limited charge

The residential air conditioner market has a significant portion of window air conditioners (WAC). Due to the compact size and small refrigerant charge, WACs are most tolerant of flammable refrigerants. Hydrocarbon (HC) refrigerants are natural substances and have significantly better environmental impacts and lower costs than conventional refrigerants like R-410A and R-22. The paper aimed to develop a WAC prototype using propane (R-290) and verify the performance metrics in the laboratory. The key of developing the WAC using a flammable refrigerant is to control the refrigerant charge under the limit of building safety regulation with the performance meeting the Energy Star standard. To minimize the charge, compact heat exchangers were utilized. To achieve the target efficiency, we collaborated with a leading rotary compressor manufacturer to develop a compressor prototype specifically optimized for R-290, able to achieve superior energy efficiency. In addition, we conducted model-based investigations to identify further charge reduction potential. Finally, with using microchannel heat exchangers to replace the fin-and-tube condenser and evaporator, the system charge can be decreased to 150 g.

42 ENGINEERING↗
DOE OSTI2026

Impact of Fermentation-Derived Substrates on Hydrogen Production in Zero-Gap Microbial Electrolysis Cells

Zero-gap microbial electrolysis cells (MECs) represent a promising platform for hydrogen production from liquid waste streams due to reduced interelectrode spacing that lowers internal resistance and enhances mass transport. However, the performance and stability of zero-gap MECs treating chemically complex feedstocks remain insufficiently characterized. Here, we operated zero-gap MECs with real, unamended, corn stover dark fermentation effluent containing a wide range of organic substrates. The MECs fed fermentation effluent achieved a maximum current density of 24 A/m2 (15+-6 A/m2 over the cycle) and a hydrogen production rate of 75 L/L-d (42+-19 L/L-d over the cycle). The substrates were consumed at different rates, indicating substrate-selective utilization by the anodic microbial community. Acetate supported high and stable current generation, whereas ethanol, formate, lactate, and amino acids induced varying degrees of inhibition depending on their concentration. Residual sugars caused pronounced current fluctuations, consistent with ongoing fermentation and local pH changes. A diverse microbial community was crucial for efficiently utilizing complex organics and maximizing electrochemical performance. These results demonstrate how and to what extent substrate composition regulates zero-gap MEC performance and that microbial community and operational conditions can be leveraged to enhance performance. These novel findings provide practical guidance for achieving robust hydrogen recovery from chemically heterogeneous real liquid waste streams.

08 HYDROGEN↗
DOE OSTI2017

Nanoquinacrine caused apoptosis in oral cancer stem cells by disrupting the interaction between GLI1 and β catenin through activation of GSK3β

Presences of cancer stem cells (CSCs) in a bulk of cancer cells are responsible for tumor relapse, metastasis and drug resistance in oral cancer. Due to high drug efflux, DNA repair and self-renewable capacity of CSCs, the conventional chemotherapeutic agents are unable to kill the CSCs. CSCs utilizes Hedgehog (HH-GLI), WNT-β catenin signalling for its growth and development. GSK3β negatively regulates both the pathways in CSCs. Here, we have shown that a nano-formulated bioactive small molecule inhibitor Quinacrine (NQC) caused apoptosis in oral cancer stem cells (OCSCs; isolated from different oral cancer cells and oral cancer patient derived primary cells) by down regulating WNT-β catenin and HH-GLI components through activation of GSK3β. NQC activates GSK3β in transcriptional and translational level and reduces β catenin and GLI1 as well as downstream target gene of both the pathways Cyclin D1, C-Myc. The transcription factor activity of both the pathways was also reduced by NQC treatment. GSK3β, β catenin and GLI1 interacts with each other and NQC disrupts the co-localization and interaction between β catenin and GLI1 in OCSCs in a dose dependent manner through activation of GSK3β. Thus, data suggest NQC caused OCSCs death by disrupting the crosstalk between β catenin and GLI1 by activation of GSK3β. - Graphical abstract: Schematic representation of inhibition of HH-GLI and WNT-β catenin cross talk by NQC through GSK3β. Diagram showing HH-GLI and WNT-β catenin pathway, where GLI1 and β catenin and other components were co-localized in a complex and co-ordinately regulate the downstream target genes. NQC activates GSK3β, which further phosphorylates and activates the β catenin and GLI1. Activated β catenin and GLI1 were degraded by proteosomal degradation pathway and unable to translocate into nucleus as a result growth of cells inhibited. - Highlights: • Nano-formulated quinacrine (NQC) activates GSK3β in oral cancer stem cells (OCSCs) in vitro and ex vivo. • NQC induces apoptosis in OCSCs by inhibiting WNT-β catenin and HH-GLI cascade in vitro and ex vivo. • NQC disrupts the interaction and co-localization between GLI1 and β catenin. • NQC-mediated disruption of the crosstalk between GLI1 and β catenin is GSK3β dependent.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2024

Adsorption of Neodymium, Dysprosium, and Ytterbium to Goethite under Varying Aqueous Chemistry Conditions

The adsorption of rare earth elements (REEs) to iron oxides can regulate the mobility of REEs in the environment and is heavily influenced by water chemistry. This study utilized batch experiments to examine the adsorption of Nd, Dy, and Yb to goethite under varying pH, electrolyte (type and concentration), and concentrations of dissolved inorganic carbon and citrate. REE adsorption was strongly influenced by pH, with an increase from essentially no adsorption at pH 3.0 to nearly complete adsorption at pH 6.5 and higher. Citrate enhanced the adsorption of REEs at low pH (<5.0), likely by forming goethite-REE-citrate ternary surface complexes. However, citrate inhibited the adsorption of REEs at higher pH (>5.0) by forming aqueous REE-citrate complexes. Ionic strength had a small influence on REE adsorption, and the presence of dissolved inorganic carbon had no discernible effect. Equilibrium adsorption was interpreted with a triple-layer surface complexation model (SCM). The selection of surface complexation reactions was guided by extended X-ray absorption fine structure spectra. An SCM with a single bidentate inner-sphere surface complexation reaction for Nd and two inner-sphere surface complexation reactions (one monodentate and one bidentate reaction) for Dy and Yb effectively simulated adsorption across a broad range of conditions in the absence of citrate. Accounting for the effects of citrate on REE adsorption required the addition of up to two ternary REE-citrate-goethite surface complexes. The SCM can enable predictions of REE transport in subsurface environments that have goethite as an important adsorbent mineral. Furthermore, this predictive capability could contribute to identifying potential REE sources and facilitating efficient extraction of REEs.

58 GEOSCIENCES↗
DOE OSTI2023

Inter-Area Oscillation Damping with Type-5 Wind Power Plant

This paper investigates the potential of using brushless excitation (BLE) for not only riding through the fault but also to damp inter-area power oscillation with the help of a synchronous generator (SG) used in Type 5 Wind Power Plant (WPP). In BLE, an auxiliary synchronous generator (ASG) behaving like an exciter is coupled and driven by the rotor of the main SG. The BLE's field current's ASG is fed by two separate loops of the automatic voltage regulator (AVR) and power system stabilizer (PSS). The AVR system implements a control loop to regulate the generator terminal voltage, VT. For the PSS, the kinetic energy of the wind turbine is utilized according to the estimated rotational speed of the synchronous generator shaft of the SG. It may mitigate the necessity of any curtailment of active power for damping. The effectiveness of the proposed control scheme is verified with a three-phase short circuit fault in a two-area power system.

brushless↗