Recently, motorship is replaced rapidly by the vessel in which Electric Propulsion System is adopted.
This system have many strong points especially in the vessel which accomplishes ice braking or underwater research and investigation mission or oil drilling etc. These kind of ships are so called Multipurpose Special Ships.
In the Electric Propulsion System of the ships, maneuverability and low vibration characteristic and low noise emission is required strictly. and so minimization of harmonics in the power line is essential for these
In order to verify the efficiency of PWM methods and to choose the best propulsion system, numerical harmonic analysis is carried out. From the analysis result , Propulsion Converter control method is selected for the Multipurpose Special Ships.
The THD (Total Harmonic Distortion) Property of Electric Propulsion System configuration of the Propulsion Converter Multipurpose Special Ships is analyzed and verified through computer simulation.
Currently the Electric Propulsion System hardware, its engineering and technology are mainly depends on european makers, On the other hand domestic level of technology is quiet low.
From these points of view, it is required that research and development in electrical propulsion system should be carried out by many researchers and manufacturers and yard workers.
I hope this paper would be a small help to those researchers and manufacturers and yard workers who engage in these field.