Superconducting magnets are key components in particle accelerators, essential for the precise guidance and focusing of particle beams. However, these magnets are subjected to stresses, like radiation and mechanical disturbances, which can lead to faults such as short circuits in the coil windings. Identifying such faults in the magnets installed in the LHC is a major challenge. A valuable method to assess their electromagnetic properties and detecting potential problems is to analyse their complex impedance over a wide range of frequencies. This thesis contributes to the advancement of CERN's STEAM (Simulation of Transient Effects in Accelerator Magnets) framework by introducing a new tool specifically designed to simulate complex impedance in the frequency domain.