Magnetic core saturation

Electrical machines or electrical equipment made of magnetic core materials (soft iron, steel) often undergo erratic behaviors during operation due to the saturation of the core as a result of the nonlinearity of circuit parameters of the core. The inrush current of slightly loaded or an unloaded transformer causes saturation of the core during energisation of which the stating current can rise ten times the rating current and even the connection of three phase induction motor in star-delta helps to reduces its starting current to avoid saturation of the lamination core. Core saturation when not controlled can generate heat with high order of harmonics which can lead to lamination breakdown, losses and reducing the life span and the efficiency of the machines. This paper presents the effect of magnetic domains alignment, core inductive reactance, material and core dimensions, current, voltage and frequency of the power supply on the saturation of the magnetic core. It also suggests the possible methods of limiting the saturation of magnetic core