azimuth thruster / for ships / electric
Min.: 500 kW (679.8 hp)
Max.: 2,600 kW (3,535 hp)
AZ-PM combines a ring-type permanent magnet electric motor, propeller and nozzle in a tightly integrated propulsion unit. It offers improved efficiency and simplicity compared to conventional geared azimuth thrusters with separate electric motors in the thruster room. The permanent magnet azimuthing thruster is a new addition to the Rolls-Royce family of thrusters, building on the design developed and verified on the permanent magnet tunnel thrusters with regard to thruster design and motor integration.
The AZ-PM meets operational requirements with focus on performance and reliability. The rotor of the motor forming a ring around the propeller blades combined with advanced blade shapes, suppresses or eliminates cavitation. The motor stator is incorporated in the nozzle which controls water flow and provides increased thrust over a wide speed range. The underwater unit can be rotated in azimuth to give steering and vectored thrust in any direction.
A steel structure carries the steering bearing and this is simply bolted into the hull. Only limited footprint space and headroom is required in the thruster room as the only components there are the slipring case that transfers power to the thruster and the compact electric steering motors. Speed control is by varying the frequency of the voltage supplied to the thruster motor.
A very high motor efficiency, 97% at nominal speed and high efficiency over the whole load range, and the submerged motor mean that no cooling equipment is required, saving space and reducing installation cost. Simple bearings in the rotor hub carry all loads, and no oil circulation pump is required.