Modeling Simulation And Analyzing Of Dynamic Stability To Marine Power Station System

Marine power station is an independent and complicated power system, and it has many special characteristics:generally the electrical devices operate in bad conditions and accidents often happen during operation; some larger electric power loads compared to the load rate of the generator often start and stop under the normal power supplying states of electric network. Generator sets often run in parallel, and it has the characteristics of strong coupling. Therefore, the dynamic processes of the marine power system take place constantly, and the range for oscillation of dynamic processes is much larger. Based on these characteristics, this paper carries out extensive research in simulation modeling and analysis of dynamic stability of the marine power station system. It is expected that some practical application in mathematical modeling, development of simulators as well as development of a new excitation controller can be explored.Firstly, a whole set of mathematical models of actual marine power station system are set up. The power station system on board of a large 5446TEU container ship is used as the research target, and a series of mathematical models are developed, including mathematical models of synchronous generators, the excitation system, the induction motors, the static load and bus. The d-q rotary shaft in a synchronous generator is used as a reference shaft, and the coupling relations of different electric devices in the marine power station are analyzed. As a result, a whole set of mathematical models for the marine power station system are developed.Secondly, marine power station training simulators and marine power station computer operation testing simulator are developed, and it is a application for modeling simulation to marine power station system. Using the techniques of physical-digital hybrid simulation and centralized simulation, as well as the techniques of modularization modeling, the training simulator and computer operation testing simulator are developed. These simulators consist of microcomputers, various kinds of physics equipment and instruments, and it satisfies the demand for education and training of marine engineer officers in marine automation technology required by the Maritime Safety Administration of the Ministry of Transport of PRC. So far the simulators have been tested for user in training programs successfully. Thirdly, a new excitation controller (AVR+PSS excitation controller) is developed. To improve the stability performance of the marine power system, a new excitation controller is developed. A power system stabilizer (PSS) is introduced into the traditional marine generator excitation system with automatic voltage regulator (AVR). The new excitation controller uses auxiliary stabilizing signals to control the generator excitation so as to improve the stability of the power system, and its basic function is to add damping to the generator oscillations by controlling generator excitation using auxiliary stabilizing signals. The simulation results show that the new excitation controller can improve not only the quality of the dynamic process but also the stability performance of the marine power system.The research results turn out to have a positive effect on improving the dynamic stability of the marine power station system and at the same time will be helpful to the training of marine engineer officers on simulators.