The simulation of small marine systems incorporating gas-turbine and diesel prime movers

In the marine environment, renewed attention has recently been given to the use of electrically-driven variable-pitch propulsion systems. Further, the growth in the offshore oil industry, with its need for specialised vessels, has provided a new application for electric propulsion in the form of dynamically positioned vessels requiring a number of electrically driven thrust propellers to keep the vessel on station. The paper demonstrates the use of a representative system model capable of predicting the dynamic response of marine systems subjected to a range of disturbance conditions, as an aid to design. Although the general form of analysis is based on traditional methods, the degree of representation of all aspects of the modelling of the electrical and mechanical system is enhanced to include complete shaft dynamic representation, including gearboxes and clutch mechanisms, together with a formalised switching and protective-device representation