How to do Thermal Impedance modelling for Foster circuit?

Question

Hi All

I have followed the demo buck converter model for understanding thermal modelling. Now I have few questions:

1. I have extracted the Ri, Ci... parameters of foster circuit from datasheet for calculating Zth_Jc (junction to case thermal impedance). I want to verify these parameters by giving the power input to this foster circuit and observe the junction temperature. e.g at Ambient temp = 25 C, power dissipated is 92 W, R1 to R4 = 0.1746  0.6273    0.6306  0.0033, C1 to C4 = 0.0094    0.9217    1.1628 0.3433

How do I give an input of 92 W to this circuit? Is there a block of heat flow to physical signal converter available in plecs? How do I model this circuit?

 

Thanks

Sneha

Answer 1

Hi Sneha,

Actually, yes. In the thermal domain component library there is both a Constant Heat Flow block and a Controlled Heat Flow block, whose input signal is generated in the Control domain. You can then place a Thermometer at the desired node and view the resulting temperature.

Best,

Kris

Comments

Thanks Kris.