Learning Forum

[Abner Campos]

I'm having difficulties running a "link" between HFSS Design and Circuit. I want to simulate a PCB model in HFSS Desingn and export its S parameters to Circuit. To do so, perform a transient simulation of the circuit considering its interconnections on the PCB.

 

Therefore, I run my simulations in HFSS Design and export the results to Circuit via Network Data Explorer -> Broadband Export Options as a Nexxim State Space model ("a type of Space model accepted in ANSYS Circuit"). Doing this way, the steady state signals of my circuit match what is expected in calculations and in practical tests. But unfortunately I don't know how to execute a "Push Excitation" option for this component, so that in HFSS Desingn I can return the fear of the due exceptions of my circuit and perform a radiated test.

 

 

I know of another method that allows this option of "Push Excitation" in which I simply drag the HFSS Desingn model to the Circuit. I can even run a transient simulation but the results don't match what I collected earlier using the export model in "Nexxim State Space".

 

 

Does anyone know how to configure the parameters I established in the figure above, so that this model that I drag from HFSS Desingn to Circuit? Or perform some kind of Push Excitation with the model created through the Broadband Export Options function?

[Dan Dv]

Hello Abner,
You can only push excitations back to HFSS when the HFSS project is linked to Circuit via a dymanic link, which is what you get when drag and drop the HFSS project into the Circuit schematic as you had discribed. None of the model types available from the Broadband Export function in NDE allow dynamic linking back to HFSS as those all produce static exported files. 
It is worth checking as to why the results are different between the dynamic link scneario and using your exported .sss file from NDE. Can you check on what options were set in NDE when you exported that file. Also what was the reported final order and fitting error for both cases? For the broadband export, that info can be found in the message manager right after the export, or saved in the *_fwslog.txt file that gets written out in parallel with the .sss file. For the dynamic link case this info is found in the log file for the transient circuit simulation.
One more thing to check, what version of AEDT are you using? I know we have made some improvements to the dynamic link process recently. 

Best regards,
-Dan