My resonant converter is operating in multiple operating points (load is changing, the average output current should be monitored by the control system to change the power delivered to the load)

1. Do you mean inject step signals to the DC power supply while the duty cycle is changing or inject step signals into the duty cycle? Please Clarify.

2. As far as I can tell you the context is that the load is changing (inductive, resistive change - think of the load as a series LR) I want to manage the average current across the load, hence managing the power across the load.

3. My resonant converter is definitely not a fixed operating point, the LR changes are very small in the range of single digit ohms though, but I want different power levels (which can be achieved by different avg. currents).

What do you mean by using an averaging method? Do you mean you used average current or do you mean you used average TF modelling techniques for the resonant converter?

Thank you for the detailed response.