In recent years, the subsynchronous oscillation (SSO), which occurs in direct-drive permanent magnetic synchronous generators (D-PMSGs)-based wind farm, has great impact on the stability of power system. The different parameters and operation conditions of D-PMSGs lead to the subsynchronous interaction (SSI) among D-PMSGs. What is more, the SSI will influence the SSO characteristics of the system of D-PMSGs-based wind farm integrated to AC network. Here, considering the difference of parameters or operation conditions among D-PMSGs in the wind farm, eigenvalue analysis, based on the smallsignal state-space model of two aggregated D-PMSGs which are equivalent to wind farm, is carried out. Then the stability and the SSI between D-PMSGs of the equivalent system can be studied, and the dominant D-PMSG can be determined based on the participation factors. Lastly, the detailed electromagnetic transient simulation model of D-PMSGs equivalent system is built in PSCAD/EMTDC. The simulation is conducted to corroborate the eigenvalue analysis. The result shows that an obvious SSI exists between two aggregated D-PMSGs. Furthermore, the different SSO characteristics among D-PMSGs in the wind farm indicate the study of SSO problem based on an aggregated D-PMSGs model may leave out some useful information.

We consider linear differential-algebraic equations (DAEs) of the form E \. x = Hx and the Kronecker canonical form (KCF) [L. Kronecker, Sitzungsberichte der K\" oniglich Preu{\ss}ischen Akademie der Wissenschaften zu Berlin, 1890Berlin, , pp. 1225Berlin, --1237 of the corresponding matrix pencils sE -H. We also consider linear control systems and their Morse canonical form (MCF) [A. Morse,

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In the present study, we assessed the genetic diversities of the Chinese Kazak ethnic group on the basis of 30 well-chosen autosomal insertion and deletion loci and explored the genetic relationships between Kazak and 23 reference groups. We detected the level of the expected heterozygosity ranging from 0.3605 at HLD39 locus to 0.5000 at HLD136 locus and the observed heterozygosity ranging from 0.3548 at HLD39 locus to 0.5283 at HLD136 locus. The combined power of discrimination and the combined power of exclusion for all 30 loci in the studied Kazak group were 0.999999999999128 and 0.9945, respectively. The dataset generated in this study indicated the panel of 30 InDels was highly efficient in forensic individual identifcation but may not have enough power in paternity cases. The results of the interpopulation differentiations, PCA plots, phylogenetic trees and STRUCTURE analyses showed a close genetic affiliation between the Kazak and Uigur group.