I'm working with a circuit which uses a common schematic for EMI filtering. I simulated the schematic and I added a 200 kHz AC signal to the main 50 Hz line, to model the differential mode noise.
My question is how this CX capacitors filter the differential noise without having path to the neutral?
As you can see, from my simulation result, the 200 kHz noise which I added to the main signal, is filtered by the LC filter (only one line is displayed)
But when I remove the connection of Cx capacitors to the Neutral, no low pass filtering occurs: