Research Of Condition Assessment For Marine Electric Propulsion System

With the great development of power electronic technology and high-power AC motor variable frequency drive technology, ship electric propulsion comes into a new flourishing period of development. Ship electric propulsion has many advantages over traditional propulsion, and is a hotspot research area in ship building. Currently ship electric propulsion will likely be one of the main trends in ship building. It is thus vitally important to study the condition assessment for ship electric propulsion.The conditional assessment for electric propulsion system is the basis for operation and fault diagnosis and status maintenance. To establish a scientific, comprehensive and rational evaluation index system and a prediction model of electric propulsion system, it is essential to choose a proper assessment approach and develop a realistic condition assessment system. It is a critical step in conditional assessment of electric propulsion systems condition. According to the running principle of marine electric propulsion system, a system of condition assessment has been established after analyzing condition information, and a prediction model of marine electric propulsion has been built after analyzing optimal combined forecasting. Then the Fuzzy Neural Network and Support Vector Machine in artificial intelligence techniques have been used to build up condition assessment model of marine electric propulsion system. The marine electric propulsion system condition assessment system was designed. Finally we conduct a simulation of condition assessment model with the test.The main results in the current dissertation are described as follows:The paper studies the marine electrical propulsion system, and puts forward the selection principle of condition assessment index. It also establishes the condition assessment Index system of marine electrical propulsion on the basis of running principle study. The Index system meets the requirements in aspects of analysis of electrical propulsion system condition assessment in certain degree.In order to predict running status of electrical propulsion system, after a further analysis of single forecasting methods and optimal combined forecasting method, the paper establishes the prediction model of marine electric propulsion system, then, emulates the model using MATLAB, the emulation result shows that the prediction model is better effective.After a further study of condition assessment process of marine electric propulsion system and format and acquisition method of condition assessment Training Sample, the paper establishes condition assessment model and used Fuzzy Neural Network and Support Vector Machine.The paper designs the marine electric propulsion system condition assessment system and its software, establishes a simplified laboratory test system based MATLAB and Visual C++. The simulation experiment of fuzzy neural network assessment model and support vector machine assessment model are implemented, and the results demonstrate the accuracy and characteristics of the two kinds of assessment methods.