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Research On Characteristic Representation Of Initial State Information And Its Relationship With Life For Electrical Apparatus

Posted on:2016-06-05Degree:DoctorType:Dissertation
Country:ChinaCandidate:F F ZhangFull Text:PDF
GTID:1222330503956044Subject:Electrical engineering
Abstract/Summary:PDF Full Text Request
The parameters’ information exists throughout the entire life cycle of the electrical apparatus, and the information in initial stage of life is called the initial state information. Then two questions should be considered: Is there any relationship between the initial state information and the lifetime of electrical apparatus? Could the initial state information be used to predict the lifetime of electrical apparatus? To predict the lifetime of a single product as early as possible, an exploratory research on above-mentioned questions is necessary and important.In order to comprehend the characteristics of life information, firstly, it is necessary to analyze the temporal property and statistical property, and then based on the method for determining the optimal fitting number and the method for determining the weighting factor through the data interval, the change law of life information is analyzed by using the least squares polynomial fitting method and moving weighted average method.To excavate the characteristics of products’ initial state information, a characteristic representation method based on the values of extreme points and endpoints is proposed. And the defect evaluation index is defined respectively in both cases of only considering the stability of information and considering the size and stability of information at the same time. Additionally, under this assumption that the initial state information weighted average of different segments are not related to the time they appeared in the process of operation, another characteristic representation method based on weighted average is proposed, in which the characteristics of initial state information are extracted from the probability weighted average of segments.Based on characteristic representation of initial state information, the analytical methods on the relationship between individual characteristics and the lifetime, and the relationship between multiple characteristics and lifetime are proposed respectively. When the relationship between individual characteristics and lifetime is a monotonic function, the typical monotonic functions can be converted into linear functions after certain transformation. So, firstly corresponding algorithm of linear regression is used to fit multiple function models, and then the optimal relation model could be determined, at last the test is carried on. After the determination of the relationship between individual characteristics and the lifetime, a new method which sets up linear model based on the mean and standard deviation is put forward from the statistical significance. In order to seek the relationship between multiple characteristics and lifetime, a method is proposed, in which firstly fuzzy C-means clustering algorithm is used to analyze the samples, and then the algorithm of BP neural network is used to seek their relationship.Finally, taking electromagnetic relay for example, the proposed methods of characteristic representation of the initial state information and the analysis method on the relationship between characteristics and lifetime are used to analyze practical cases, and validate the feasibility and the validity of these methods. The methods presented by this dissertation not only could be applied to relay products, but also to other products with similar characteristics.
Keywords/Search Tags:electrical apparatus, initial state information, characteristic representation, lifetime, electromagnetic relay, contact resistance
PDF Full Text Request
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