Design of Traveling Wave Location Method for Transmission Line Fault Based on EMD-TEO

Abstract

<p>With the rapid development of the social economy and the continuous extension of Internet technology, China’s power grid has entered the ranks of large-scale, high-voltage, and intelligent. The main purpose of the fault location of the transmission line is to eliminate hidden trouble and restore the fault line in time to ensure the safe and stable operation of the power system. With the advent of the smart grid, higher requirements are put forward for fault location accuracy, while the traditional wavelet transform and Hilbert-Huang transform have larger defects.</p><p>Therefore, this paper extensively analyses the generation and characteristics of fault traveling waves in transmission line fault, which proves that the traveling wave location method has higher location accuracy than the fault analysis method. Among them, the two-terminal traveling wave positioning method only uses the arrival time of the initial traveling wave, avoiding the principled defects and locating the dead zone of the single-terminal traveling wave positioning method, so the two-terminal traveling wave positioning method is generally used. The key of the two-terminal traveling wave location method is that it can accurately detect the arrival time of the initial traveling wave head. Although the Hilbert-Huang Transform (HHT) method can be used to detect the arrival time of the initial traveling wave head, the problem of inaccurate detection or failure of the wave head may arise when the instantaneous frequency of the IMF component decomposed by the Hilbert-Huang transform is used because of the mode aliasing in the empirical mode decomposition algorithm. Based on the above analysis, an empirical mode decomposition (EMD) combined with the Teager energy operator(TEO) is proposed for the traveling wave fault location of transmission lines. A large number of simulations prove that the EMD-TEO method in this paper can solve the problem of inaccuracy or failure of the HHT method using instantaneous frequency to detect the arrival time of wave head, and has higher fault location accuracy.</p>