Tool/software:
Hi Expert,
My customer using this part of design tools.
They curious two section parameter then want to know how to fill it the right answer as their currently design.
1.regulator CM noise source impendance(CSRC/RSRC/LSRC) ?
2.CM Choke impedance model parameter ? what is Lmag/Lmag2/Lmag3)
Eddie
Hello Chao,
1. If we model the DC-DC regulator side and Load using a Thevenin equivalent, whatever ZThevenin we would be generally dominated by capacitance – which we call CSRC. The resistive component is RSRC and inductive component is LSRC. The customer has to estimate how much CSRC he would see for his particular system. This CSRC determines how much noise voltage swing we would see on the EMI filter. If you don't have these values, the values mentioned in the quick start calculator are a good starting point. you can use those default values for a generic system.
2. If you try to model the CM choke impedance vs frequency data using a choke model - then the model parameters are called Lmag/Lmag2/Lmag3.
The following links can help you in that regard - How2power.com article series: How active EMI filters reduce common-mode emissions in single- and three-phase applications – Part 1: An overview; Part 2: Modeling ferrite chokes; Part 3: Modeling nanocrystalline chokes; Part 4: Loop gain analysis
Thanks and regards
Naresh
