Design of an active EMI filter with hybrid magnetic core for motor drives

In the operation of an induction motor drive system, the common-mode noise generated by the motor drive adversely affects the system's normal operation and interferes with other properly functioning equipment. Passive EMI filters are large in size, while the application of an active EMI filter (AEF) can effectively reduce the volume of the passive EMI filter.Therefore, an AEF is designed for the motor drive system in use. The design process includes analysis of the motor drive system, magnetic component design and Topology and device selection. Field tests show that the designed active EMI filter achieves conducted noise suppression in the 0.15–10 MHz range, with a maximum suppression effect of 12 dB.