Research On Distinguishing Inrush Current Of Power Transformer Based On Wavelet Analysis

In recent years, with the development of electric power, we have found that we can not live without electricity, whether it is a variety of electronic products, or the Internet, the transmission of multimedia, are not separated from the role of electricity. In this high-speed development of the community without the support of electric power, we can not be so easy to obtain a variety of knowledge, which is undoubtedly a great impact on our life. Followed with power related problems, which in order to make the power system can be a safe and stable operation of the power system, power transformer selection and protection has become a big problem, once the transformer problems will have serious consequences for the normal operation of the system, and due to the high cost of transformers, maintenance difficulties and so on, so do the power transformer protection is very important. People use the method of differential protection to improve the reliability and sensitivity of the transformer to prevent the failure of the transformer. The differential protection caused by magnetizing inrush current is the most difficult to control in the process of differential protection. Around these problems, the relay protection researchers have proposed a lot of methods for the identification of inrush current.In this paper, a review is made on the typical excitation inrush current identification method, and its advantages and disadvantages are briefly described. The complex problem of transformer inrush current transient process is analyzed, and the scientific analysis and Research on the mechanism and the related factors of the transformer inrush current, and the related factors, and the comprehensive display of the waveform characteristics of the current. On the basis of understanding the theory of wavelet analysis, the basic principle of wavelet packet analysis method and its implementation algorithm are described. From the viewpoint of energy, a new method of measuring the wavelet packet is proposed. The state of the transformer inrush current and the internal fault current are simulated in different conditions. The new data is obtained by the new data analysis. The energy spectrum of 4,3 (W) is obtained. Because the inrush current has different mechanism, so it can get different energy spectrum. Through the comparison of different time spectrum, we can draw the corresponding data, and integrate all the data into a reasonable criterion. This method is concluded by a lot of experiments, so this method can be widely used in various wavelet analysis.