Abstract
Propeller loads fluctuate in various route environment such as crushing submerged or floating objects, or air ventilation. The electric propulsion system can alter the torque/speed characteristics of a diesel engine to meet any forced load, required response time and continuation of ship's controllability.
Authors have reported a method for calculating dynamic characteristics of the electric propulsion system. Proposed technique utilize both control circuit and power system analysis for synthesizing a propulsion system to meet given performance requirements.
Analytical waveforms of propeller loads are supposed rectangular, caused by correlative motion of ship's pitching and sea waves resulted in air ventilation.
Constant speed control system is established on static Leonard system, which contains current limit circuit and buffer circuit to suppress higher current fluctuation proposed in this paper.
Numerical responses with rectangular loading to propeller on the model ship are presented and are also compared to those of the diesel propulsion system to estimate influences on combustion of main diesel engine.