Research On Operation Simulation And Modeling Of Marine Diesel Generator Sets

Operation of marine diesel-generator is an. important part in operation of power station, the capacity of power station relys on the quantity of diesel-generator sets which are in state of parallel operation. The stability of parallel operation is tightly connected with that of ship power system. The construction of an accurate dynamic model for operation of diesel-generator sets is important to control, simulation and performance analysis.The research on parallel operation of diesel-generator sets deals with diesel-generator model, model of parallel operation control and electric load model, etc. Among these, although there are some different methods to construct models for diesel-generator, most are only for diesel-generator single set. With diesel-generator model as core, a mathematic model for parallel operation of diesel-generator sets is set up.Ship power station in teaching and study ship YUKUN being taken as a reference, diesel-generator model, electric load model and control system model for parallel operation are developed respectively. Simulation model of parallel operation is developed based on that. The MATLAB/SIMULINK software is selected as the simulation tool to carry out simulation analysis, and simulation results are compared with test data in ships.Synchronous generator model is an important part of diesel-generator set model, which have serious effect on calculation accuracy and simulation speed. In the paper, the stator transient effect for dynamic performance is considered, synchronous generator model is amended, Seventh phase state equation sets are introduced, and dynamic simulation accuracy is improved. The situations in which diesel-generator is loaded and unload as well as starting process are simulated, the simulation result corresponds to the practical situation, and also validates the simulation model correct.On the condition of simplified parameters, load model of induction motor is developed, which have most effect on power system stability. Under the unity coordinator, using PARK transform, variable impedance method is applied to state equation group of diesel-generator set, avoiding the solution of differential-algebra-equation group, calculation speed is improved. The simulation is made by SIMULINK tool with a satisfactory result.Physical rules and characteristic of synchronism in parallel operation are analyzed, according to control principle of parallel operation simulation method of load shift during parallel operation is put forward. The concept of stability degree in parallel operation is defined to denote the stability degree; the stability of parallel operation is analyzed. The contradiction of calculation accuracy and simulation speed is considered, the models are simplified to use in simulator of power station in ship.Parallel operation of diesel-generator sets is an important field in research on ship power station, in the paper, synchronous generator model is amended, and variable impedance method is presented to develop model of induction motor load, and the model for parallel operation of diesel-generator sets is put forward, the new concept of stability degree in parallel operation is first presented, the solution of oscillation angle parameters is given. These models are significant for control, simulation and performance analysis on ship power station, and will lay the important foundation for constructing simulator of ship power station.