Methodical design of EMI filters for power electronics

Development of filters for electromagnetic interference can significantly be accelerated, when methodical design flows are applied. This contribution describes a workflow to predict EMI behavior of power electronic devices, considering the source and spreading of interference and the physical setup of the system. Special emphasis is laid on the placement of passive components, which severely influences the performance of filters. These effects can be traced back to magnetic coupling between components. Therefore investigations on stray fields of passive components had to be carried out, which enable the derivation of placement rules and furthermore an automated placement. Using the proposed method in the design stage reduces development costs and allows a statement on achievable performance with selected components.