LLC converter voltage gain plots

I watched the video on designing a 600W LLC converter and would like to know how to derive the voltage gain curves that are shown during the presentation, ideally using a simulator like Simetrix/Simplis.

Thank you!

You can draw a basic LLC circuit in any simulator, and feed it with square wave while stepping frequency and/or load, and then you can observe the resonant tank gain at these frequencies similar to the graphs you attached. This way, what the simulator will show you, is not quite exact (no parasitics are considered), but it is good enough to design and predict the behavior of a physical LLC converter.

There are multiple ways of performing a simulation of the gain curve waveform for specific ranges or set of multiple curves. You can explore the parameters based on your given specs/requirements or perform a monte-carlo for a set of curves.

Kind Regards,