Active shield for low-frequency magnetic fields

The magnetic field generated by power-frequency electrical installations has provoked concern in recent decades. One solution for a strong mitigation of the magnetic field is the use of an active shielding system. This technique consists in a suitable current driven in a suitable conductive loop in order to generate an opposite magnetic field. The research project has been focused on the improvement of the aspects related to the implementation, the control, and the costs of active shield. A new control strategy has been developed in order to extend the possibilities to apply this technique and to improve the actual performances. A prototype which implements the control strategy has been developed and successfully tested. Moreover, some comparisons between active and passive shields have been performed.