Research On Multi-method Integrated On-line Monitoring And Diagnosis System For Marine Diesel Engine

As the heart of the ship, diesel engine is the most important equipment in the ship; its working state directly affects the safety of the whole ship. So real-time and on-line monitoring the diesel engine has a very far-reaching significance. Once any fault occurs in diesel engine, it may lead to the paralysis of the ship power system, and will cause great economic loss. So real-time and on-line monitoring the diesel engine has a very far-reaching significance. As a large and complex mechanical system, marine diesel engine has a great diversity of faults and one fault phenomenon is often caused by a variety of reasons. It’s difficult to detect the fault reason and position by single method or parameter in the process of monitoring and diagnosis. Based on the above, in this thesis, taking the8000kW marine salvage vessel as the research object, introduce an on-line oil monitoring integrated sensor and construct a multi-method integrated on-line monitoring and diagnosis system for the ship. The main content and conclusions of this thesis are as follows:(1) Summarize several common monitoring and diagnostic techniques used in the diesel engine condition monitoring and fault diagnosis. Give a simple introduction to the performance parameter method, vibration analysis method, instantaneous angular speed method and oil analysis method, and analyze the advantages of each method in practical applications as well as shortcomings. Based on these advantages and disadvantages, combining several of these methods to form a comprehensive monitoring and diagnosis system has been studied by the engineers and technicians, and has good application in practice.(2) After analyzing various techniques of the oil analysis method and the application status of on-line oil monitoring technology, an on-line oil monitoring integrated sensor is proposed and designed. This sensor can real-time obtains the viscosity, moisture content of the lubricating oil and the concentration and image of the wear debris, so that making the reliability and comprehensiveness of on-line oil monitoring improved.(3) FWD-1moisture sensor and FWS-2viscosity sensor made by Shenzhen Xianbo Technology Co., Ltd. were selected in this on-line oil monitoring integrated sensor system. A series of performance experiments with both the sensors were carried out. These experiments show that the two sensors have high precision, fast response, well stability and strong anti interference performance and other advantages. Based on these advantages, the feasibility and reliability of the two sensors used in actual on-line oil monitoring were verified. And then, according to the principle of the two sensors, the calibration methods for the sensors monitoring the actual lubricating oil are given. At last according to the layout of lubricating oil system in the real ship, the effective installation methods for the sensors are given.(4) Taking the8000kW marine salvage vessel of Salvage Bureau as the research object, by obtaining several different types of parameters, a multi-method integrated on-line monitoring and diagnosis system for the ship’s power plants was established. Finally, the application program for the monitoring and diagnosis system was developed on VC++6.0, LabVIEW and other software.