Fuzzy Modeling for Representation of Magnetization Curves and ysteresis Loops

• Main Authors: Rong-Gaong HAN, 韓榮廣
• Other Authors: Pei-Hwa Huang
• Format: Others
• Language: zh-TW
• Published: 1994
• Online Access: http://ndltd.ncl.edu.tw/handle/40467136476712538242

碩士 === 國立海洋大學 === 電子工程學系 === 82 === The main purpose of this thesis is to report the application of fuzzy modeling to the representation of magnetization curves and hysteresis loops of transformers. The transformer, which plays an important role in the transmission of electric energy, is made of ferromagnetic materials for which the magnetization curve and hysteresis loop are the most fundamental characteris- tics. It is difficult to find the mathematical representation of the high nonlinearity due to saturation of the material. Based on the concepts of fuzzy sets and the specific features of magnetization curves and hysteresis loops, this thesis tries to apply the method of fuzzy modeling to the mathematical representation of magnetization curves and hysteresis loops. First the original data are grouped into some clusters using hierarchical cluster analysis. Then a membership function is defined for each cluster to make a fuzzy partition of the input domain, and the method of least squares approximation is used for curve fitting of each cluster. Numerical examples are demonstrated to show the validyt of the presented method.