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At least 1,585 records · Page 88
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Machine Learning-Assisted Stability Boundary Determination of Multiport Autonomous Reconfigurable Solar Power Plants

The multiport autonomous reconfigurable solar (MARS) power plant is a promising solution to integrate renewable resources and energy storage systems into the alternating current (ac) power grid and an high-voltage direct current (HVdc) link. In the MARS system, various input power sources are connected to the individual submodules (SMs) through direct current (dc)–dc converters. However, the presence of external power sources can result in unbalanced capacitor voltages of SMs, thereby violating stability constraints under multiple/diverse operating conditions. This article aims to address the gap by accurately determining the stability boundary of the MARS system. As such, a novel machine learning (ML)-assisted energy balancing control (EBC) criterion is proposed. Further, in conjunction with a refined EBC, this approach ensures balanced capacitor voltages across various types of SMs, significantly enhancing the overall system efficiency. The proposed EBC criterion effectively controls EBC activation and deactivation, achieving remarkable accuracy. Both power systems computer aided design (PSCAD)/electromagnetic transients including direct current (EMTDC) simulations and control hardware-in-the-loop (cHIL) tests are conducted to validate the feasibility and efficiency of the proposed method. By combining the EBC and ML-assisted EBC criterion, efficient energy management is achieved for systems featuring multiple input power sources, such as MARS. This approach enables the system to fully exploit its potential across an expanded operational range while upholding high-efficiency standards.

14 SOLAR ENERGY↗
DOE OSTI2020

Materials Data on Ac2O3 by Materials Project

Ac2O3 crystallizes in the trigonal P-3m1 space group. The structure is three-dimensional. Ac3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ac–O bond distances ranging from 2.47–2.84 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Ac3+ atoms to form OAc4 tetrahedra that share corners with six equivalent OAc6 octahedra, corners with six equivalent OAc4 tetrahedra, edges with three equivalent OAc6 octahedra, and edges with three equivalent OAc4 tetrahedra. The corner-sharing octahedra tilt angles range from 17–56°. In the second O2- site, O2- is bonded to six equivalent Ac3+ atoms to form OAc6 octahedra that share corners with twelve equivalent OAc4 tetrahedra, edges with six equivalent OAc6 octahedra, and edges with six equivalent OAc4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcCl3 by Materials Project

AcCl3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. Ac3+ is bonded in a 9-coordinate geometry to nine equivalent Cl1- atoms. All Ac–Cl bond lengths are 3.05 Å. Cl1- is bonded in a trigonal non-coplanar geometry to three equivalent Ac3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcBr3 by Materials Project

AcBr3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. Ac3+ is bonded in a 9-coordinate geometry to nine equivalent Br1- atoms. There are six shorter (3.21 Å) and three longer (3.26 Å) Ac–Br bond lengths. Br1- is bonded in a trigonal non-coplanar geometry to three equivalent Ac3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcF3 by Materials Project

AcF3 is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ac3+ is bonded to twelve F1- atoms to form AcF12 cuboctahedra that share corners with four equivalent AcF12 cuboctahedra, corners with eight equivalent FAc4F8 cuboctahedra, corners with sixteen equivalent FAc4F4 tetrahedra, edges with eight equivalent AcF12 cuboctahedra, edges with eight equivalent FAc4F4 tetrahedra, faces with four equivalent AcF12 cuboctahedra, and faces with six equivalent FAc4F8 cuboctahedra. There are eight shorter (2.64 Å) and four longer (2.83 Å) Ac–F bond lengths. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to four equivalent Ac3+ and four equivalent F1- atoms to form distorted FAc4F4 tetrahedra that share corners with eight equivalent AcF12 cuboctahedra, corners with eight equivalent FAc4F8 cuboctahedra, corners with eight equivalent FAc4F4 tetrahedra, edges with four equivalent AcF12 cuboctahedra, edges with four equivalent FAc4F8 cuboctahedra, edges with twelve equivalent FAc4F4 tetrahedra, and faces with six equivalent FAc4F4 tetrahedra. All F–F bond lengths are 2.64 Å. In the second F1- site, F1- is bonded to four equivalent Ac3+ and eight equivalent F1- atoms to form distorted FAc4F8 cuboctahedra that share corners with four equivalent FAc4F8 cuboctahedra, corners with eight equivalent AcF12 cuboctahedra, corners with sixteen equivalent FAc4F4 tetrahedra, edges with eight equivalent FAc4F8 cuboctahedra, edges with eight equivalent FAc4F4 tetrahedra, faces with four equivalent FAc4F8 cuboctahedra, and faces with six equivalent AcF12 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcH3 by Materials Project

AcH3 is alpha bismuth trifluoride structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Ac3+ is bonded in a distorted body-centered cubic geometry to fourteen H1- atoms. There are eight shorter (2.51 Å) and six longer (2.90 Å) Ac–H bond lengths. There are two inequivalent H1- sites. In the first H1- site, H1- is bonded to four equivalent Ac3+ atoms to form HAc4 tetrahedra that share corners with twelve equivalent HAc6 octahedra, corners with sixteen equivalent HAc4 tetrahedra, edges with six equivalent HAc4 tetrahedra, and faces with four equivalent HAc6 octahedra. The corner-sharing octahedral tilt angles are 55°. In the second H1- site, H1- is bonded to six equivalent Ac3+ atoms to form HAc6 octahedra that share corners with six equivalent HAc6 octahedra, corners with twenty-four equivalent HAc4 tetrahedra, edges with twelve equivalent HAc6 octahedra, and faces with eight equivalent HAc4 tetrahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on RbAcTe2 by Materials Project

RbAcTe2 is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Rb1+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Rb–Te bond lengths are 3.61 Å. Ac3+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Ac–Te bond lengths are 3.61 Å. Te2- is bonded in a body-centered cubic geometry to four equivalent Rb1+ and four equivalent Ac3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KAcTe2 by Materials Project

KAcTe2 is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. K1+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All K–Te bond lengths are 3.56 Å. Ac3+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Ac–Te bond lengths are 3.56 Å. Te2- is bonded in a body-centered cubic geometry to four equivalent K1+ and four equivalent Ac3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcCuO3 by Materials Project

AcCuO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Ac3+ is bonded to twelve equivalent O2- atoms to form AcO12 cuboctahedra that share corners with twelve equivalent AcO12 cuboctahedra, faces with six equivalent AcO12 cuboctahedra, and faces with eight equivalent CuO6 octahedra. All Ac–O bond lengths are 2.79 Å. Cu3+ is bonded to six equivalent O2- atoms to form CuO6 octahedra that share corners with six equivalent CuO6 octahedra and faces with eight equivalent AcO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Cu–O bond lengths are 1.97 Å. O2- is bonded in a distorted linear geometry to four equivalent Ac3+ and two equivalent Cu3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiAcTe2 by Materials Project

LiAcTe2 is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Li1+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Li–Te bond lengths are 3.43 Å. Ac3+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Ac–Te bond lengths are 3.43 Å. Te2- is bonded in a body-centered cubic geometry to four equivalent Li1+ and four equivalent Ac3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcTlTe2 by Materials Project

AcTlTe2 is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Ac3+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Ac–Te bond lengths are 3.53 Å. Tl1+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Tl–Te bond lengths are 3.53 Å. Te2- is bonded in a body-centered cubic geometry to four equivalent Ac3+ and four equivalent Tl1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NaAcTe2 by Materials Project

NaAcTe2 is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Na1+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Na–Te bond lengths are 3.48 Å. Ac3+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Ac–Te bond lengths are 3.48 Å. Te2- is bonded in a body-centered cubic geometry to four equivalent Na1+ and four equivalent Ac3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcTe3 by Materials Project

AcTe3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ac3+ is bonded to twelve Te1- atoms to form AcTe12 cuboctahedra that share corners with four equivalent AcTe12 cuboctahedra, edges with eight equivalent AcTe12 cuboctahedra, edges with sixteen equivalent TeAc4Te8 cuboctahedra, faces with four equivalent AcTe12 cuboctahedra, and faces with eight equivalent TeAc4Te8 cuboctahedra. There are four shorter (3.32 Å) and eight longer (3.74 Å) Ac–Te bond lengths. There are two inequivalent Te1- sites. In the first Te1- site, Te1- is bonded to four equivalent Ac3+ and eight Te1- atoms to form distorted TeAc4Te8 cuboctahedra that share corners with twelve equivalent TeAc4Te8 cuboctahedra, edges with eight equivalent AcTe12 cuboctahedra, edges with eight equivalent TeAc4Te8 cuboctahedra, faces with four equivalent AcTe12 cuboctahedra, and faces with ten equivalent TeAc4Te8 cuboctahedra. There are four shorter (3.32 Å) and four longer (3.74 Å) Te–Te bond lengths. In the second Te1- site, Te1- is bonded in a square co-planar geometry to four equivalent Ac3+ and eight equivalent Te1- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcTiO3 by Materials Project

AcTiO3 is (Cubic) Perovskite structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. Ac3+ is bonded to twelve equivalent O2- atoms to form AcO12 cuboctahedra that share corners with twelve equivalent AcO12 cuboctahedra, faces with six equivalent AcO12 cuboctahedra, and faces with eight equivalent TiO6 octahedra. All Ac–O bond lengths are 2.84 Å. Ti3+ is bonded to six equivalent O2- atoms to form TiO6 octahedra that share corners with six equivalent TiO6 octahedra and faces with eight equivalent AcO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Ti–O bond lengths are 2.01 Å. O2- is bonded in a distorted linear geometry to four equivalent Ac3+ and two equivalent Ti3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcN by Materials Project

AcN is Wurtzite structured and crystallizes in the hexagonal P6_3mc space group. The structure is three-dimensional. Ac3+ is bonded to four equivalent N3- atoms to form corner-sharing AcN4 tetrahedra. All Ac–N bond lengths are 2.55 Å. N3- is bonded to four equivalent Ac3+ atoms to form corner-sharing NAc4 tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcAgTe2 by Materials Project

AcAgTe2 is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Ac3+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Ac–Te bond lengths are 3.41 Å. Ag1+ is bonded in a body-centered cubic geometry to eight equivalent Te2- atoms. All Ag–Te bond lengths are 3.41 Å. Te2- is bonded in a distorted body-centered cubic geometry to four equivalent Ac3+ and four equivalent Ag1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcSe3 by Materials Project

AcSe3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ac3+ is bonded to twelve equivalent Se1- atoms to form a mixture of face and corner-sharing AcSe12 cuboctahedra. There are six shorter (3.13 Å) and six longer (3.51 Å) Ac–Se bond lengths. Se1- is bonded in a 2-coordinate geometry to four equivalent Ac3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on AcAu3 by Materials Project

AcAu3 crystallizes in the hexagonal P6_3/mmc space group. The structure is three-dimensional. Ac3+ is bonded to twelve equivalent Au1- atoms to form a mixture of distorted corner and face-sharing AcAu12 cuboctahedra. There are six shorter (3.27 Å) and six longer (3.47 Å) Ac–Au bond lengths. Au1- is bonded in a 4-coordinate geometry to four equivalent Ac3+ and six equivalent Au1- atoms. There are four shorter (2.96 Å) and two longer (3.05 Å) Au–Au bond lengths.

36 MATERIALS SCIENCE↗