The present article highlights the atypical power grid resilience of the northernmost point of the African countries against repeated acts of vandalism on its MV distribution lines. To counter this threat, the present article reports a comparison between a 3-wire and 4-wire MV power grid in the event of a single-phase or three-phase short-circuits. The evolution of the voltage of the healthy phases during a single-phase fault and the impact on the power supply signal are mathematically studied. The study shows that an adequate resizing of the protection devices is sufficient to operate the MALT system in complete safety without its neutral wire. Thus, by allowing saving copper wire, this finding is actually a turning point in the implementation of the malt system. To better contextualize this result, which was actually initicated by an unpleasant experience, the article begins with a historical assessment of the 30 kV 4-wire MALT electrical distribution systems and a technical calibration of its specificities in relation to the two conventional practices of standard IEC 60038.

In this paper, we report on numerical simulations of incompressible MagnetoHydroDdynamic flows by a two dimensional finite difference scheme associated to an appropriate projection method performed to characterize velocity-pressure formulations along the specified MHD duct by solving the set of differential equations of magnetohydrodynamics. In the present calculation, a working electrolytic solution is considered in order to bring up the application of the magnetohydrodynamic micropump. Numerical results show the characteristics of flow velocity, pressure distribution and their convergence tests. The computations aim to optimize the flow rate of a given MHD micropump regarding to its geometrical dimensions and the external electromagnetic excitation

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