Active Electromagnetic Interference Filter (AEF) for Power Electronics

Wide-bandgap semiconductors operating at high switching frequencies allow power electronic systems, e.g. On-Board Chargers (OBCs) for electric vehicles, to reach high efficiency and power densities. 

The fast semiconductor switching in combination with circuit parasitics generate conducted and radiated emissions. To achieve electromagnetic compatibility, the emissions of power converters into the grid must be properly attenuated. Typically, Passive EMI Filters (PEFs) are used, whose components are large in volume and weight, which also adds additional cost to each system. Especially Common Mode Chokes (CMCs) get quite bulky when a certain Common Mode (CM) Insertion Loss (IL) is needed. 

An Active EMI Filter (AEF) uses an amplifier within the EMI filter, which is used to cancel electromagnetic noise, like active noise cancelling in a headset. Therefore, it is capable to significantly reduce the size, weight, volume and cost of the needed passive components.

PhD Candidate:

Patrick Körner