Configuration of special kind of fan

Hi there,
I want to integrate a special kind of fan into my KNX Home Assistant setup. This fan is controlled via an analogue actor in KNX. For example it’s disabled when I send a current between 0,36V and 0,45V to a pin. 0,46V to 0,55V is low, 0,56V to 0,65V medium and 0,66V to 0,75V high speed.
There are are two group addresses to control this fan. 5/1/0 is to set a voltage and 5/2/0 to retrieve the current voltage.
Now I somehow need to calculate values to map this to a percentage or steps. I didn’t find a way to to calculations in a KNX configuration. I think I need some kind of templates. Can you guide me to the right direction?
Greetings
JudGer