Analysis And Study Of Insulator Leakage Current Characteristics Based On DSP

Many domestic and foreign blackouts are caused by line fault. With the formation of our national interconnected power grid, network security issues become increasingly prominent. Line fault may trigger a chain reaction of more serious consequences. Overhead transmission lines all year exposed to the atmosphere, either insulators or conductors are vulnerable to weather and environment, Accumulate to a certain extent may fail, and even lead to disaster. Leakage current, as best reflects the physical state of insulator, the analysis of it can help us clearly understand the health of insulators and effectively conduct flashover warning. So the leakage current collected in the DSP system structure is mainly studied in this subject and the relevant state characteristics were analyzed.First the paper introduces the Empirical mode decomposition (EMD) algorithm. Then the problems of modal mixing and end effects which inherent in EMD algorithm are given a specific improvement.Then the paper describes the algorithm of removing signal interference of the leakage current.First introduces the basics of signal noise. Then compare the FFT, wavelet noise reduction (choose several different wavelet threshold) and EEMD denoising algorithm. Through the comparison of the waveform before and after denoising and the ratio of the amplitude from the fundamental and third harmonic before and after denoising,point out that the use the EEMD algorithm to the noise reduction is reasonable and effectiveness.Then the back is the three segments of leakage current analysis, choose the leakage current waveform, RMS, Hilbert spectrum characteristics and so on to show the characteristics of each stage. Then we main analyze the leakage current characteristics of safe area and propose two new characteristics:time-frequency entropy and maximum energy value growth rate. Through the experiments, we know that these two characteristics clearly show the state of insulator, which can be used as the characteristics to effective warning of the flashover.Finally this paper describes the system structure of leakage current acquisition and analysis base on DSP (Digital Signal Processing). A brief account is given to the DSP2812chip and the acquisition system structures are also given in the field and experimental environment. Then allocate the memory of DSP2812and achieve the data processing algorithm.