Abstract: A drive arrangement for a cycloidal marine propulsion unit including at least two electrical blade motors each associated to a respective blade for pivoting thereof, each blade motor being operationally coupled to a respective blade drive for actuating the corresponding blade motor. The at least two blade drives each include a respective blade drive power converter operationally coupled to a first common intermediate DC-link, wherein the at least two blade drives being configured to feed power from the first common intermediate DC-link to their respective blade motors, and to feed regenerative power from their respective blade motors to the first common intermediate DC-link. The disclosure also concerns a marine propulsion unit having such a drive arrangement, and a method of operating such a drive arrangement.

Abstract: A drive arrangement for a cycloidal marine propulsion unit including at least two electrical blade motors each associated to a respective blade for pivoting thereof, each blade motor being operationally coupled to a respective blade drive for actuating the corresponding blade motor. The at least two blade drives each include a respective blade drive power converter operationally coupled to a first common intermediate DC-link, wherein the at least two blade drives being configured to feed power from the first common intermediate DC-link to their respective blade motors, and to feed regenerative power from their respective blade motors to the first common intermediate DC-link. The disclosure also concerns a marine propulsion unit having such a drive arrangement, and a method of operating such a drive arrangement.

Abstract: An arrangement and a method for installing a propulsion unit to a hull of a ship. The propulsion unit comprises an upper part of the propulsion unit attachable to the hull of the ship and a lower part of the propulsion unit where to a propeller shaft is rotatably supported, and the upper part of the propulsion unit having flanges to attach the flanges tightly to the hull, and wherein there is an aperture in the bottom of the hull where to the propulsion unit is to be installed. The arrangement comprises a plurality of watertight covers covering openings in the bottom of the hull and a plurality of watertight covers covering openings in the top of the upper part of the propulsion unit, wherein the arrangement comprises a removable hull-side cover covering at least the opening under it, and at least one removable propulsion unit side cover covering the opening under it and facing the opening, and the removable covers are bolted from the hull-side.

Abstract: A ship comprising a hull having a transom and a bottom, and an azimuthing propulsion unit arranged to the bottom of the ship hull, which azimuthing propulsion unit comprises a propeller. The azimuthing propulsion unit comprises an exposed operation mode in which the propeller sets, behind the transom of the hull and that the azimuthing propulsion unit is rotatable and comprises a protected position mode in which the azimuthing propulsion unit stays below the hull of the ship.

Abstract: An arrangement and a method for installing a propulsion unit to a hull of a ship. The propulsion unit comprises an upper part of the propulsion unit attachable to the hull of the ship and a lower part of the propulsion unit where to a propeller shaft is rotatably supported, and the upper part of the propulsion unit having flanges to attach the flanges tightly to the hull, and wherein there is an aperture in bottom of hull where to the propulsion unit is to be installed. The arrangement comprises a plurality of watertight covers covering openings in the bottom of hull and a plurality of watertight covers covering openings in the top of the upper part of the propulsion unit, wherein the arrangement comprises a removable hull-side cover covering at least the opening under it, and at least one removable propulsion unit side cover covering the opening under it and facing the opening, and the removable covers are bolted from the hull-side.

Abstract: A ship comprising a hull having a transom and a bottom, and an azimuthing propulsion unit arranged to the bottom of the ship hull, which azimuthing propulsion unit comprises a propeller. The azimuthing propulsion unit comprises an exposed operation mode in which the propeller sets, behind the transom of the hull and that the azimuthing propulsion unit is rotatable and comprises a protected position mode in which the azimuthing propulsion unit stays below the hull of the ship.

Abstract: An exemplary propulsion arrangement is disclosed which includes two propulsion units situated side by side at the stern of a ship at opposite sides of a center line of the hull of the ship. Each propulsion unit can include a hollow support structure attached to the hull, a chamber attached to the support structure, an electric motor within the chamber, a propeller connected through a shaft to the electric motor, and a pivotably supported rudder at the rear end of the chamber. Each propulsion unit can be mounted in a toe-out position forming a horizontal tilt angle (?) of 0.5 to 6 degrees to the center line (CL) of the hull.

Abstract: An exemplary propulsion arrangement is disclosed which includes two propulsion units situated side by side at the stern of a ship at opposite sides of a center line of the hull of the ship. Each propulsion unit can include a hollow support structure attached to the hull, a chamber attached to the support structure, an electric motor within the chamber, a propeller connected through a shaft to the electric motor, and a pivotably supported rudder at the rear end of the chamber. Each propulsion unit can be mounted in a toe-out position forming a horizontal tilt angle (?) of 0.5 to 6 degrees to the center line (CL) of the hull.

Abstract: An exemplary propulsion arrangement includes at least one propulsion unit situated at the stern of a ship having a hull with a horizontal water line (WL) and a center line (CL). The propulsion unit can include a hollow support structure attached to the hull, a chamber attached to the support structure, an electric motor within the chamber, a propeller at the front end of the chamber, and a pivotably supported rudder at the rear end of the chamber. The propulsion unit can be mounted so that the shaft line (SL) forms a vertical tilt angle (?) in a range of 1 to 8 degrees in relation to the water line (WL) so that the front end of the chamber is lower than the rear end of the chamber in relation to the water line (WL).

Abstract: An arrangement is disclosed for supplying propulsion power to a contra rotating propellers (CRP) propulsion system in a marine vessel, which arrangement can include a first propeller driven by a rotating power unit, and a second propeller driven by an AC motor. The second propeller can be rotated in an opposite direction relative to the first propeller, wherein an AC generator is driven by the rotating power unit and the AC generator is electrically connected to the AC motor. The rotation speed of the second propeller is between for example 95% and 150% of the rotation speed of the first propeller. The AC motor and the AC generator have the same electrical frequency. The pole number of the AC generator is from for example 2 to 40 and the pole number of the AC motor is from for example 2 to 40.

Abstract: An arrangement for steering and supplying propulsion power to a contra rotating propeller(s) (CRP) propulsion system in a marine vessel is disclosed. The arrangement can include a first propeller, a second propeller driven by an AC motor, and an AC generator. The AC motor and AC generator can have the same electrical frequency. Another electrical power source can be electrically connectable to the AC motor in parallel to the AC generator. A shaft of the second propeller is mounted rotatable in a support structure which is attached to a hull of the marine vessel, and a rudder is supported in a manner allowing pivotal movement of the rudder relative to the support structure.

Abstract: An arrangement is disclosed for supplying electric power to a propulsion system of a marine vessel having a propeller motor, which is connected to an AC generator. The AC generator supplies electric energy to the propeller motor. The AC generator is rotated by a rotating power unit. A frequency converter is electrically connectable in parallel to the AC generator and the frequency converter supplies electric power from a second power unit.