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Currently, there is a substantial demand for mathematical models of wind power generators in power system simulation tools. This can be explained by two factors: (i) wind now contributes a significant part of the power produced in different power systems around the world; (ii) one requirement to design an intelligent renewable power infrastructure is to rely on accurate and open models to simulate the different components of an electric power system (EPS). This article presents the development and implementation of second-generation generic wind turbine generators (WTGs) models in the Power System Toolbox (PST)—open source software for power system transient simulation. The evaluation of these models is performed using simulation studies on two test systems: a single machine infinite bus (SMIB) system, and the IEEE 68-Bus system. Transient stability and small signal analysis are performed using Type-3 and Type-4 wind turbines models to assess the performance of such models. [ABSTRACT FROM AUTHOR]

The Southern Brasília Orogen is a Neoproterozoic belt that occurs along the southernmost border of the São Francisco Craton where the Andrelândia Nappe System represents the subducted sedimentary domain and is divided into three allochthonous groups, of which the ages and P-T conditions of metamorphism are studied here. The basal unit, the Andrelândia Nappe, exhibits an inverted metamorphic pattern. The base of the structure, composed of staurolite, garnet, biotite, kyanite, quartz, and muscovite, marks the metamorphic peak, whereas at the top, the association of the metamorphic peak does not contain staurolite. The Liberdade Nappe, the middle unit, presents a normal metamorphic pattern; its base, close to the Andrelândia Nappe, shows paragneiss with evidence of in situ partial melting, and towards the top, coarse-grained staurolite schist is found. The staurolite-out and melt-in isograds are coincident and parallel to the main foliation. Thus, the shear zone that limits the nappes is syn-metamorphic, reheating the underlying Andrelândia Nappe and influencing the establishment of metamorphic inversion. This suggestion is supported by the monazite chemical ages, which indicates that the Andrelândia Nappe metamorphic peak (586 ± 15 Ma) is younger than that of the Liberdade Nappe (622.3 ± 7.6 Ma). The upper unit, the Serra da Natureza Klippe, bears a typical high-pressure granulite mineral assemblage that is composed of kyanite, garnet, K-feldspar, rutile, and leucosome, as well as a metamorphic peak at 604.5 ± 6.1 Ma. This tectonic assembly, with inverted and non-inverted metamorphic patterns and generation of klippen structures, is consistent with exhumation models and a strong indentor located in the lower continental crust. [ABSTRACT FROM AUTHOR]