FEM Voltage drop simulator

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A very active Youtuber With KiCad and FEM at https://www.youtube.com/@panire3/videos

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unfortunately this is only a manual processā€¦
what it would make a real change is a plugin or an external tool like the one that Nico is implementingā€¦

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hello! Iā€™m the author of nikfemm and of the original kicad plugin. I made it because the main problem of embedding a 3d simulator into kicad is the dependency hell this results into. nikfemm is dependency-less (opencv is used for visualization only) and it uses a fast 2.5d approach (basically multiple coupled 2d simulations for each layer) to avoid building a big and slow 3d mesh so it would be easy to include directly into kicad without worrying about any additional dependencies to keep track of and it would be very lightweight.
the only problem is that nikfemm only solves 2d and multilayer 2d problems so Iā€™m stuck at thinking if its worth the hassle of including a simulator in kicad that cannot for example find parasitics (inductance capacitance etc.)
what do you think?

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Inductance and related eddy current effects are pretty essential for power electronics, so a 2D resistance-only simulation has pretty limited value. Note that it is often power electronics applications that care about dc resistance as well.

But, it is better than nothing, and right now 3D FEM is difficult in many ways.

Thatā€™s just one engineerā€™s opinion. Perhaps more will weigh in.

John

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I would second what was said by @JohnSG . Most of the guys I know that use FEM or similar methods inside / together with an Electronics CAD tool use it to extract parasitics (R,L,C) or doing power/ signal integrity simulations for which (I think) 3D models are unavoidable.

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Hi @nikisalli
having a plugin for current density and voltage drop would be useful indeed.
Have you had a look at the @thefloe Tobias plugin?
It seems derived from your solverā€¦ I have tested it on some of my boards and it seems to make a good job. It is developed using the new kicad API so it should be easier to maintaining it.
Adding the simulator inside kicad could be a more complex task, compared to develop an external plugin.