Automatic control of marine propellers
Electric Ship. New Concepts, Power Control Systems, Design Constraints

To regulate a propeller's speed Ω or propulsion power, it is necessary, even summarily, to have a mathematical representation. The representation of the torque C_r of a propeller is often of the form C_r = kΩ², in a more general way, k being a function of navigation conditions ([D 5 610], § 1).

When considering the inertia involved in servoing, we need to take into account the overall inertia, including the motor itself, the shaft and the propeller itself (as well as its gearbox, if any). The propeller drives water, so its inertia is partly variable. Despite...