Transmission-line oscillator: problem with PSS

Hi all,

I am trying to simulate an oscillator with PSS. In this oscillator, two transmission lines are used to implement the tank. The model of the transmission line was extracted from HFSS as RLGC model.

When I simulated, PSS failed, and it mentioned that it cannot support directly to distributed components. It also suggested me to use Harmonic balance method.

As I see from PSS, I have "Shooting" and "Flexible balance",

So, is it correct that I should choose "Flexible balance" ?

I tried to use it, PSS failed again. Perhaps I do not know how to set the paramters in Flexible balance correctly.

If anyone used Flexible balance mode in PSS before, please suggest me how to simulate my oscillator in this mode.

Thank you in advance :)

DYL

The oscillators are simulated generally by using "shooting method". The most important parameters are "stability time" and " forecasted oscillation frequency"...
The others can be rest as default..
"Flexible Balance" method is usually used for lightly nonlinear circuits and sometimes divider and mixer circuis.
I use always Shooting Method and if you set the oscillation frequency and stability time correctly, PSS will find a solution.
But before doing this, the circuit should be tested in terms of feedback and gain and phase margin..

Hi,

Actually I tried to play around with Shooting method, but could not get PSS run. Varying tstab and guess frequency did not help.

I think perhaps it is about using Flexible balance .... which I still don't know how to set parameters correctly

Perhaps, your oscillator doesn't work ? Could you check it ?

Hi BigBoss,

My oscillator is working, as I checked from transient analysis. Do you have any idea to set parameters in flexible balance ?

DYL