Solving Inductive Noise and EMI Problems with 3D FEA Simulation

3D FEA Software Solves Tough Inductive Noise Problems

by Peter Markowski, Envelope Power, Ansonia, Conn. A previous article on 3D electromagnetic finite element analysis (FEA) software explained how a new generation of these tools, which includes EMS from EMworks, can be used for optimization of high-frequency transformer design (see the reference.) In this article, I would like to show how the same software can help to solve difficult layout problems in electronics, especially power electronics. Switched-mode power supplies are notorious for hard-to-eliminate noise problems simply because we cannot completely avoid proximity of high-power switching circuits and sensitive controls. Good engineering practices such as minimizing high-frequency current loops and voltage surfaces, perpendicular arrangement of potential source-target sets and using large copper planes for shielding are naturally a must. But without any way of quantifying problematic phenomena it is impossible to know if we are pushing our luck and if we did the best we could within the given constraints. In the end, we have to make a choice between unnecessarily conservative designs and risking costly, time consuming (and stressful!) fixing of prototypes. To read more here