In this paper, we identify the common mode impedance of a parallel converter cell and the impact of each converter on the entire system. The study is done in two cases, favorable when all the sane converters, and degraded when at least one converter in insulation fault. We also put the distinction load type to see their effect on the propagation path. The equivalent method of the Thevenin and impedance circuit is used for the prediction electromagnetic interference generated by these converters. The good knowledge of these electromagnetic interferences allows a proper optimization of the filters (volume/efficiency), and the optimum choice of exploitation of the whole of the cell. The model is tested by PSpice simulation with a wide frequency range up to 30 MHz.

Modular Multilevel Converter (MMC) is one of the most promising topologies for high power-medium voltage application. However, the use of MMC in variable speed drive applications is still limited. This is due to the fact that the fluctuation of the submodules capacitor voltage is large at low speed constant torque operation. This paper proposes an improved balancing approach based on Space Vector Pulse Width Modulation (SVPWM). The proposed method uses only one SVPWM, which not only simplifies the calculation but also reduces the submodules capacitor fluctuation and the circulating current in the MMC, thereby allowing the operation of MMC-based variable speed drive over the entire operating speed range and improve the converter efficiency. The closed loop operation of the MMC-based variable speed drive is verified through extensive simulations.

This paper considers whether non-trivial identities are satisfied by certain ‘plactic-like’ monoids that, like the plactic monoid, are closely connected with combinatorics. New results show that the hypoplactic, sylvester, Baxter, stalactic, and taiga monoids satisfy identities. The existing state of knowledge is discussed for the plactic and Bell monoids.

{We consider a velocity tracking problem for the Navier-Stokes equations in a 2D bounded domain. The control acts on the boundary through an injection-suction device, and the flow is allowed to slip against the surface wall. We study the well-posedness of the state equations, linearized state equations, and adjoint equations. In addition, we show the existence of an optimal solution and establish the first order optimality condition.}

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The compounds 1-naphthyliminoferrocene{,} 1{,} and 2-methyl-1-naphthyliminoferrocene{,} 2{,} were prepared by the reaction of ferrocenecarboxaldehyde and the corresponding amine{,} 1-naphthylamine and 2-methyl-1-naphthylamine with one drop of pyrrolidine as catalyst{,} in CH2Cl2{,} under inert atmosphere. The compounds were fully characterized by elemental analyses{,} matrix-assisted laser desorption/ionization - time-of-flight mass spectrometry (MALDI-TOF){,} FT-IR{,} 1H and 13C NMR as well as two-dimensional{,} NOESY{,} COSY and HSQC{,} NMR spectroscopy. Mossbauer spectroscopic studies were performed to characterize the iron species in both compounds. The solid-state molecular structures of compounds 1 and 2 were determined by single crystal X-ray diffraction. Analysis of the electrochemical behaviour of complexes 1 and 2 was performed by cyclic and square wave voltammetry. Compounds 1 and 2 were tested as chromogenic and electrochemical sensors for Hg2+.

It is known that zinc alloys with iron group metals have better corrosion resistance than pure zinc. Owing to the corrosion resistance of these alloys, Zn–Fe coatings are widely used in automotive industry...

We show that a physical trigger, a non-ionizing infrared (IR) radiation at wavelengths strongly absorbed by liquid water, can be used to induce and kinetically control protein (periodic) self-assembly in solution. This phenomenon is explained by considering the effect of IR light on the structuring of protein interfacial water. Our results indicate that the IR radiation can promote enhanced mutual correlations of water molecules in the protein hydration shell. We report on the radiation-induced increase in both the strength and cooperativeness of H-bonds. The presence of a structured dipolar hydration layer can lead to attractive interactions between like-charged biomacromolecules in solution (and crystal nucleation events). Furthermore, our study suggests that enveloping the protein within a layer of structured solvent (an effect enhanced by IR light) can prevent the protein non-specific aggregation favoring periodic self-assembly. Recognizing the ability to affect protein-water interactions by means of IR radiation may have important implications for biological and bio-inspired systems.