State Assessment Of Ship High Temperature Fresh Water System Based On Hypersphere Support Vector Machine

This passage uses the high temperature fresh water system as the research object and assess the state of the performance degradation phase,which is the stage before the failure occurs.Taking into account the external environment,select the export parameters of each equipment for evaluating parameters.Then use the hyper sphere support vector machine to build model for real-time condition assessment.First,compare and analyze current popular condition assessment methods,choose the hyper sphere support vector machine as the condition assessment method which suits for dealing with the problems of the nonlinear and multidimensional model of small sample data,considering the problem that the high temperature fresh water system has the characteristics of having more subsets and system parameters.Next,research and analyze deeply for setting up the training sample and kernel function of the hyper sphere support vector machine.For the obtaining of training sample,use the import parameter and performance equation of the subsets of the high temperature fresh water system.Get 'the performance equation of each facility from conducting experiments.The heat transfer characteristics equation and resistance characteristic equation of plate heat exchanger are obtained by equal velocity method.The Q-H performance equation of centrifugal pump are obtained by the least square method.Then using the experiment data to perform each facility performance equation error analysis so that we can get the ideal range of training sample.As for the kernel function,use the Gaussian kernel as the kernel function which has the good analytical and theoretical analysis conveniently advantage,modeling the same data samples when the kernel parameter is 0.5,2,3,5,7,10 respectively.Pick up the kernel parameter as 5 after analyzing the number of support vector,classification effect,spherical shape and other aspects and considering model hypersphere sensitivity,stability requirements.Finally,use the above results to build a complete ship high temperature fresh water system state evaluation model to perform the condition assessment of three different operating condition A,B and C.The operating condition A and B have no faults,only the operating parameters are different.The operating condition C has the leakage fault,which is achieved by the centrifugal pump cock.The final assessment result is Health value FA? Health value FB>Health value Fc.It conforms to the expected results,proving the effectiveness of this method and certain actual application value.In this passage we put forward some ideas and outlook of the hyper sphere support vector machine applying to the real ship and the method improvement.