Power grids are increasingly integrating renewable energyEnergy sources, leading to larger power fluctuations. Aluminium smeltersAluminium smelter require alternative solutions for power flexibilityFlexibility, particularly through cell amperage modulations. However, this can induce magnetohydrodynamicMagnetohydrodynamic (MHD) modeling (MHDMagneto-Hydro-Dynamic (MHD)) instabilitiesInstability, lowering cell performance. As cell amperage increases or decreases, metal pad upheaval and thus the levels of liquids within the cell change rapidly while the position of anodesAnode remains constant. This significantly impacts the distribution of anodic currents as well as the MHD stabilityMHD stability of the cells. In this work, ALUCELLALUCELL software was used to help understand the phenomena at stake when modulations are applied. ModelingModeling results were analyzed and compared to observations in aluminium reduction cellsAluminium reduction cells. Ultimately, new developments prove essential for adapting our MHDMagneto-Hydro-Dynamic (MHD) models in ALUCELLALUCELL software to more precisely describe the transition from one initial steady state to another over this brief modulation period, enabling better control of cell operations during amperage modulations.