Transient Stability Analysis And Simulation Of Marine Integrated Full Electric System

Marine integrated full electric system combines two main systems of present marine platform: power system and propulsion system, integrates integrated utilize of electric energy and the power supply for propulsion, and it's a new electric power propulsion system brought forward in 1990s. With the development of marine integrated full electric system, not only the electric power system consists of high voltage network and low voltage network, but also its network structure gets more and more complex, so the analysis and research of transient stability analysis become stringent. But due to the beginning of the research is so late and the knowledge accumulation is lacking, so breaking through the key technique that restricts the design of marine integrated full electric system is significant. This paper does some basic research on the transient stability of marine integrated full electric system.After consulting to a great deal of Chinese and English datum and basing on the work of the ship operator, a dynamic mathematic model is set up for a typical structure of marine integrated full electric system. Later using equivalent method and node voltage method the steady state mathematic model is set up and tidal current is calculated by Newton method which provide initial value for transient stability analysis. Based on the mathematic model and initial value of steady state, and referred to the mature theory of electric power system transient stability analysis in the land, the simulation arithmetic of marine power system transient stability is set up. The rotor movement equation is solved and the current injected into generator and the admittance matrix are amended. Then the network equationis iteratively solved.In this paper, the time domain simulation of the system transient procedure upon sudden load change is carried out basing on Matlab6.0, and the simulation graphs such as voltage, current, electric power and electric power etc are shown. We can exert the electric power system transient stability criterion and judge the transient stability based on the variable curve of the generator relative electric power angle. At the same time the maximal capability of increasing or decreasing load is obtained in the allowable variable range of the voltage and frequency. In order to validate the mathematic model simulation arithmetic and simulation program, the simulative experiments of sudden load change of the system consisting of both generators parallel connection , three generators parallel connection and four generators parallel connection are carried . The results of experiment indicate that the precision of the time domain simulation arithmetic is high and the research step> means and experimental scheme adopted in this paper are true and promethean.