Abstract: A system for transforming a variable output into an input having a desired speed value, including a transmission receiving the output having a first speed (Ve) and producing the input having a second speed (Vgen), first, second and third sensors producing data corresponding to the first speed (Ve), second speed (Vgen) and a power demand (Pdem) for the input, a ratio set point controller, a ratio controller and a speed controller. The ratio set point controller receives the data and calculates an available power (Pav), a stability level of the system (S,U1,U2), a desired value for the first speed (Ve), and a desired value and rate of change for the transmission ratio. The ratio controller interfaces the ratio set point controller and actuates the transmission to change the transmission ratio to the desired value following the desired rate of change. The speed controller changes the first speed (Ve) until the second speed (Vgen) corresponds to the desired speed value.