Study On Key Technologies Of Marine Power Equipment Diagnosis System In Distributed Resource Environment

The condition monitoring and fault diagnosis for marine power equipment which is the key component of ships has been widely concerned by domestic and foreign scholars and research organizations. However, the shortage of criterion knowledge has been the key obstacle to the development of fault diagnosis for marine power equipment. Thus there is a great request to build a distributed resource environment of fault diagnosis for the marine power equipment, in which the diagnosis data, cases and knowledge can be shared and new criteria for diagnosis can be also refined using the technologies of DM (data mining) and so on.Aiming at the present separation condition of the researches in the field of fault diagnosis for marine power equipment, the significance of building the distributed resource environment of condition monitoring and fault diagnosis for the marine power equipment was discussed. And several key issues about building the distributed resource environment were analyzed. Then the classification and functions of roles in the distributed resource environment were defined. Furthermore the classification features and expression methods of the sources were discussed. Finally the architecture and establishment steps of the distributed resource environment were given, which served to advance the fault diagnosis system for the marine power equipment toward actual practice as a solid foundation.The feature classification of instrument and equipment in the condition monitoring and fault diagnosis was in depth analysis. And the high-efficient automatic acquisition and integration of data acquired by instrument with serial port were realized. Taking advantage of the folder monitoring and message communication, the networked integration of data from instrument with its own computer was also achieved. Based on this, an automatic data acquisition system of experimental center for monitoring and analysis was established, and good effect had been proved by practical running. The data format analytical algorithm for the analytical instrument was put forward and come true based on cluster and similarity analysis, which laid down a good foundation for the further use of enciphered data. Under the shifting condition of ships, it is necessary to integrate the maintenance information in the process of condition monitoring and fault diagnosis. A problem of integration after the maintenance information was modified had been solved conveniently and effectively using the program code automatic generation technology in this article. The integration level of detection information was improved through the use of these technologies, which established a strong foundation to facilitate better use of monitoring data in the distributed resource environment.As we all know, it's quite difficult to acquire criterion knowledge for the condition monitoring and fault diagnosis in machinery. The traditional approach depends on constant summary of experiences from the experts. However, the acquired knowledge is probably inaccurate and inefficient. With the benefit of network, the different companies and users that have the same equipments can be organized to form an integrated information source in order to share the original data and diagnosis knowledge collected in the actual monitoring diagnosis. And more accurate diagnosis knowledge may be acquired using knowledge mining and information fusion. In the field of the condition monitoring and fault diagnosis for marine power equipment, the approach of obtaining diagnosis knowledge through DM was discussed in this paper. Aiming at the clustering algorithm in DM, a new generation algorithm of pedigree chart was proposed and realized. The shortcoming of applying the traditional normal distribution to acquire the monitoring data's baseline was analyzed. Maximum entropy method was brought in to calculate the criteria's baseline value and the algorithm procedures of maximum entropy was also achieved using.net programming language. Requirements for the application of maximum entropy were analyzed. For the data from diesel engine stand test, the absolute value's criteria and rate of change's criteria of element concentration in spectrometric oil analysis were computed separately by maximum entropy method and normal distribution method. The precondition requirement of using maximum entropy method to dig out the criterion baseline was gained through data analysis. According to DM's present characteristic of quick change and rapid development, a method to construct an extendable DM application system based on the reflective technique was proposed, which was of important signification in the foundation of distributed resource environment.Analyzing the features of fault diagnosis knowledge for the marine power equipment, the system which used database technology to store the knowledge of production rules was put forward. The corresponding storage organization was studied. A convenient and flexible method to match and diagnose the knowledge automatically was also proposed. For the present fault diagnosis, considering the fuzziness of some knowledge, which failed to be represented in rules but only had corresponding case samples, so Neural Network (NN) had been brought in to use for storing this class of knowledge. With the help of my own programming, the construction, training, storage, loading and diagnosis of NN had been carried out, which provided the powerful support for the distributed resource environment.In addition, the concept and meaning of knowledge service were discussed. The diagnostic service was provided externally in the form of remote knowledge service. The framework of remote knowledge service system based on web service technology was represented. The operation form of external service for different nodes in the distributed resource environment was solved. Taking the remote knowledge service of wear debris' image processing for example, the construction procedure of knowledge service was described in detailed.Finally, the system platform of the marine remote fault diagnosis, which was built in this paper based on the idea of distributed resource environment, was introduced including design concept, expansive interface, operation effect, and so on.