Propulsion System for New Large Hydrographic Survey Vessel “SHOYO”
By Mitsuo Kosaka, Shinichi Kodama, Tetsuya Shimozono
Hydrographic survey vessel of Maritime Safety Agency (MSA) “SHOYO” went into commission on March 20, 1998, and she became the largest hydrographic survey vessel of MSA in size and functions. She was built at Tamano Works of Mitsui Engineering & Shipbuilding Co., Ltd. as a survey vessel on continental shelf, marine environment and for foreseeing earthquake or volcanic eruption etc.
To improve the accuracy of survey data, we adopted alternating current of electric propulsion system that was new to MSA. The propulsion force and general electric load are completely got from the main electric system in all operation mode. The engine for the main generator is ADD diesel engine (Advanced Diesel-engine Development: 6ADD30V type), which was developed as a marine diesel engine with high power and high reliability by national project, and put to the first practical use for ship.
Generally speaking, the specifications for MSA vessels vary in high level. SHOYO is provided with various sorts of her own security countermeasure for electric propulsion system to avoid its unexpected stop. To protect electric instruments from adversary effect of harmonic distortion of electricity which is generated in propulsion thyristor-motors, we adopted two kinds of filters. One is AVR (automatic voltage regulator) that is installed for all advanced survey system, and another is transformer with noise-cut filter (440V-100V) that is installed for all navigation system and other instruments.
SHOYO is now playing an active part in the advance line of MSA hydrographic survey vessels, attracting various persons' attention. Her principal items are as follows;
･ Gross tonnage & Total length 3,128t × 98.0m
･ Engines for main generator 2,980kW(4,050PS) × 720rpm × 2
(packaged in soundproof box and installed on anti-vibration support)
･ Main generators 3,830kVA(2,800kW) × 720rpm × 2
･ Auxiliary generators 450kVA(360kW) × 720rpm × 2
(designed for standing by main generators and power source at anchoring)
･ Propulsion motors 2,100kW × 290rpm × 2
(thyristor-motor type; controllable within the range of (± 29rpm 〜 ± 290rpm))
─Reprinted from Journal of the M.E.S.J., vol.33, No.8─
