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Thruster and propeller devices may be of the type controllable pitch propeller (CPP) with fixed speed, controllable speed with fixed pitch propeller (FPP), or controllable pitch and speed in combination. In conventional positioning systems the final thruster pitch or speed set-point signals are determined from stationary propeller-force-to-speed/pitch relations based on data from the propeller manufacturer. However, these relations are strongly influenced by the local water flow around the propeller blades subject to hull design, operational philosophy, vessel motion, waves and water current. In this paper a method based on torque control and power control of the propeller and thruster devices is presented. Instead of calculating the propeller speed and pitch set-point signals based on stationary functions, the propeller-force-to-moment and-power relations are used. Power and torque control in combination gives a significant improvement in the performance and the stability of the electrical power plant network, while the positioning accuracy and bandwidth are improved as well