Propulsion System and Power Plant

Sikuliaq is outfitted with a diesel electric propulsion system consisting of four MTU diesels(two 16V-4000 and two 12V-4000), each with a Kato generator powering the propulsion bus at 690 VAC,60 Hz with step down transformers powering the ship service 480 VAC bus. 

Propulsion is via a pair of 2,238 kW Siemens variable speed motors powering Wärtsilä 360° azimuthing Z-drives with four-bladed, fixed pitch, heavy duty ice propellers. 

There is a single 686 kW Elliot Gill 360° azimuthing bow thruster powered by a 1150 hp A/C motor variable frequency drive motor.

Power for propulsion is provided from the 690 VAC propulsion bus to the two Siemens propulsion motors through propulsion transformers and IGBT chopper drives, and to the bow thruster through the bow thruster converter and variable frequency drive.

Combinations of the Z-drives and bow thruster are employed by an electronic DP (dynamic positioning) system for station keeping or precision vessel maneuvering.

The vessel operates using an Integrated Power Plant (IPP) concept. 

As stated above, the system consists of four Kato generators powering the propulsion bus at 690 VAC,60 Hz with step down transformers powering the ship service 480 VAC bus. A 208/120 VAC bus for clean power is fed from the 480 VAC bus. 

A 480 VAC emergency bus is powered from the ship service switchboard, or by the emergency generator. The 480 VAC emergency bus powers a 280/120 VAC emergency load bus via step down transformers. 

The entire system is controlled through an Integrated Monitoring Alarm and Control System along with a Siemens Power Management System to control the priority of loads on the high voltage bus.