System and method for distribution network fault locating based on improved double-terminal traveling wave method

Abstract

The invention relates to a system and a method for distribution network fault locating based on an improved double-terminal traveling wave method. The system comprises a terminal measurement module and a control center host computer, wherein the terminal measurement module is composed of a sensor module, a microprocessor module, a wireless communication module and a power supply module. The method comprises the following steps: a current traveling wave signal measured by a current transformer is calculated to obtain each current phase with a time scale; the phase current is decoupled, and a line mode component is selected as a traveling wave propagation mode for fault locating; an obtained traveling wave signal is uploaded to the control center host computer; the head of a travelling wave is detected, and rapid intrinsic mode decomposition is carried out on the line mode component; the arrival time of the travelling wave is determined; the wave speed is measured; and a fault is located. By adopting the system and the method of the invention, higher detection accuracy is achieved, the consistency of wave speeds of a fault traveling wave in three line sections formed by a fault point and three measuring points is ensured, and accurate online fault traveling wave speed determination is realized.

Description

technical field [0001] The invention belongs to the technical field of distribution network fault location, in particular to a distribution network fault location system and method based on an improved double-terminal traveling wave method. Background technique [0002] Due to its complex topology, the distribution network has relatively high requirements for fault location. There are many traveling wave measurement algorithms based on measuring the time when the fault signal travels to the end to determine the fault point, the core of which is: 1. The capture of the signal, that is, the detection of the fault traveling wave head, is based on the characteristics of the fault signal using signal analysis 2. For the measurement of wave velocity, the accuracy of traveling wave velocity is another key factor for accurately locating the fault point by using the traveling wave method. The propagation speed of the fault traveling wave is related to the actual parameters of the tra...

AI Technical Summary

Problems solved by technology

[0005] Neither the fixed value nor the wave velocity measured off-line can guarantee the accuracy of the fault traveling wave velocity.

However, for the fault location method that uses the reflected wave at the fault point or the reflected wave at the opposite end bus to eliminate the influence of wave velocity, when the reflected wave is attenuated to the point where it cannot be measured or there is no reflected wave, its positioning reliability and positioning accuracy are difficult to guarantee.

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