Research On Fault Diagnosis Technology Of Main Propulsion System For Working Mother Ship

The electric propulsion has become a development direction of the marine propulsion by its superiorities. As electric propulsion system is used more and more widely in Dynamic Positioning ship, therefore, developing fault diagnosis technology of the marine electric propulsion system has theory and practical significance to complete propulsion technology.The propulsions of ROV working mother ship are made up of converter, three-phase asynchronous motor, gearbox and propeller. It's a typical electric propulsion ship. The subject took the working mother ship as a research object, did a simulation research for its 75kw main propulsion system, concluded the kind of faults and finished the research of fault diagnosis based on neural network.The research of the subject was separated into two parts. In the first part, summarized the working principle of the CFPWM and SVPWM vector control system, established a corresponding simulation model under the environment of MATLAB, and compared dynamic and stable characteristics of the two Control Methods. When summarized the mathematical model of propeller and Dynamic Positioning ship, established a simulation model of the working mother ship's main propulsion based on vector control, and analyzed dynamic and stable characteristics of the propulsion system. In the second part, summarized the faults of Converter and propeller, took the voltage of motor, current of stator, torque of propeller and rotational speed of motor as monitor objects and finished the research of fault diagnosis based on neural network.In the simulation process, some sub systems were predigested when they are set up.The results of simulation and analysis indicated that the marine electrical propulsion simulation model can well simulate the working conduction of actual system, and the fault diagnosis system based on neural network also can diagnose the fault of the electric propulsion system.The topic has made a detailed study in propulsion system's fault diagnosis and made a meaningful exploration for completing the electric propulsion system.