+ Post New Thread
Results 1 to 6 of 6
  1. #1
    Newbie level 6
    Points: 84, Level: 1

    Join Date
    Nov 2019
    Posts
    12
    Helped
    0 / 0
    Points
    84
    Level
    1

    Impedance of Z(1,1) is not 50 ohm in HFSS

    Hi, i have designed the 3D spiral coil using HFSS and terminated it with 50 ohm impedance using single Lumped port. But the data table of Z(1,1) shows resistance value in terms of milliohms. What changes should be made to get correct values of resistance and inductance? How to obtain proper S11 at 10MHZ?

    •   AltAdvertisement

        
       

  2. #2
    Advanced Member level 5
    Points: 14,463, Level: 29

    Join Date
    Apr 2014
    Posts
    2,258
    Helped
    903 / 903
    Points
    14,463
    Level
    29

    Re: Impedance of Z(1,1) is not 50 ohm in HFSS

    Looking at your screenshot, I suspect that you have a metal object in parallel to your lumped port.

    I'm not an HFSS user, but in all my EM tools a lumped port is between the metals, and looks like a port (not like a metal).

    Click image for larger version. 

Name:	nodummy.PNG 
Views:	3 
Size:	92.5 KB 
ID:	156627

    Click image for larger version. 

Name:	inductor_3D_1port_detail.PNG 
Views:	2 
Size:	13.2 KB 
ID:	156628
    Last edited by volker@muehlhaus; 22nd November 2019 at 14:07.


    1 members found this post helpful.

    •   AltAdvertisement

        
       

  3. #3
    Junior Member level 1
    Points: 1,347, Level: 8

    Join Date
    Mar 2013
    Posts
    19
    Helped
    9 / 9
    Points
    1,347
    Level
    8

    Re: Impedance of Z(1,1) is not 50 ohm in HFSS

    make sure you converge for very low deltas. better even look at the variation of z11 rather than S. something like delta s of 0.002 may be better for inductor. if results are far off, something is wrong with geometry..


    1 members found this post helpful.

    •   AltAdvertisement

        
       

  4. #4
    Newbie level 6
    Points: 84, Level: 1

    Join Date
    Nov 2019
    Posts
    12
    Helped
    0 / 0
    Points
    84
    Level
    1

    Re: Impedance of Z(1,1) is not 50 ohm in HFSS

    Quote Originally Posted by dpres View Post
    make sure you converge for very low deltas. better even look at the variation of z11 rather than S. something like delta s of 0.002 may be better for inductor. if results are far off, something is wrong with geometry..
    Hi.. thanks for your prompt response.

    Hi Volker.. thanks for your valuable suggestion. I have defined the port between terminals using rectangular sheet. The data table shows some non-zero values. Let me check with that values.



  5. #5
    Advanced Member level 5
    Points: 14,463, Level: 29

    Join Date
    Apr 2014
    Posts
    2,258
    Helped
    903 / 903
    Points
    14,463
    Level
    29

    Re: Impedance of Z(1,1) is not 50 ohm in HFSS

    Looks much better, and imag{Z} scales with frequency as expected. I think you've solved your issue now.


    1 members found this post helpful.

    •   AltAdvertisement

        
       

  6. #6
    Newbie level 6
    Points: 84, Level: 1

    Join Date
    Nov 2019
    Posts
    12
    Helped
    0 / 0
    Points
    84
    Level
    1

    Re: Impedance of Z(1,1) is not 50 ohm in HFSS

    Quote Originally Posted by volker@muehlhaus View Post
    Looks much better, and imag{Z} scales with frequency as expected. I think you've solved your issue now.
    Issue fixed. Inductance value is around 637nH. Thank you.



--[[ ]]--