The Modeling And Simulation Of Marine Propulsion System For Twin-Diesel Engine-Controllable Pitch Propeller

The modeling and simulation of ship diesel engine-controllable pitch propeller for single-engine propulsion system and twin-engine propulsion system are systematically studied in this paper.In the paper, the MAK9M25 engine is chosen as the modeling object, and the single-engine propulsion system and twin-engine propulsion system are mainly studied. Firstly, the whole single-engine propulsion system is divided into several blocks according to the modular modeling, such as coordinated control subsystem, main engine subsystem, governor subsystem, and ship and propeller subsystem. The whole modeling is based on the modeling and logic links of all subsystem, and the single-engine propulsion system is simulated by the command signals given by the coordinated control system.Secondly, two kinds of working condition for twin-engine propulsion system is discussed, one is the two engines and one propeller paralleling control propulsion system, the other is two engines and two propellers propulsion system. The simulation and modeling of the two conditions are based on the single-engine propulsion system. In actual fact, the combined power propulsion system is mainly consisted of four engines and two propellers, but there is high degree of symmetry of the two shafts, for improving the modeling speed, only one shaft is discussed in this paper. For the former condition, the speed and the load distribution in parallel operation are the key point, and in the later condition, the differences of load distribution are researched between inside propeller and outside propeller when turning the ship.Thirdly, a management interface based on the simulation results is established for easy viewing of all kinds of propulsion system. The environment for designing the interface is the GUIDE in Matlab.The simulation results show that the shaft speed, propeller pitch angle and ship speed can all track the command signals in the established single-engine propulsion system which makes a good foundation for the twin-engine propulsion system. In the t- wo engines and one propeller propulsion system, the simulation results show that the power can be equivalent after parallel operation when the ship needs to speed up from cruising. In the ship turning of two propellers, the load for the inside propeller is larger than the outside load.