High-voltage transmission network series-parallel line fault distance measurement method, device and system based on traveling wave energy change characteristics

Abstract

The invention discloses a high-voltage power transmission network series-parallel line fault distance measurement method, device and system based on traveling wave energy change characteristics. The method comprises the steps of acquiring fault zero-mode voltage traveling wave signals and zero-mode current traveling wave signals of measurement points at the two ends of a line, extracting a traveling wave signal component with the frequency omega based on the fault zero-mode voltage traveling wave signal and the zero-mode current traveling wave signal to obtain a zero-mode voltage traveling wave component and a zero-mode current traveling wave component, calculating traveling wave energy of measuring points at two ends of the line, determining a fault section based on the traveling wave energy and a fault section positioning criterion, and obtaining a fault point calculation formula corresponding to the fault section, substituting the traveling wave energy of the measuring points at thetwo ends of the line and the related physical parameters corresponding to the fault section into the fault point calculation formula, and calculating the accurate position of the fault point. According to the method, only the fault initial traveling wave head needs to be extracted, support of a synchronization system is not needed, the traveling wave speed does not need to be obtained, and influences of signal synchronization errors and wave speed changes on fault section judgment in high-voltage long-distance power transmission are avoided.

Description

technical field [0001] The invention belongs to the technical field of power grid fault location, and in particular relates to a fault location method, device and system for hybrid lines of a high-voltage transmission network based on characteristics of traveling wave energy changes. Background technique [0002] The modern power system is a complex power transmission and distribution system, which is responsible for the transmission and distribution of electric energy in multiple regions. When a transmission line fails, especially a permanent failure, it will cause a large-scale power outage, affecting social production and residents' lives, and It will have a great impact on the stability of the system. This requires the ability to quickly locate the fault point after a fault occurs, troubleshoot and eliminate the fault, and restore the normal operation of the line as soon as possible. [0003] Compared with a single overhead transmission line or cable line, the line-cabl...

AI Technical Summary

Problems solved by technology

From the perspective of the propagation characteristics of traveling waves, due to the different line parameters of line lines and cable lines, the wave speeds on the two types of lines are inconsistent, and the wave impedance before and after the connection point is discontinuous. The existing single line positioning method cannot be directly applied to hybrid Line fault location

The earlier hybrid line fault location was mainly devoted to solving the difficulties caused by the inconsistent wave speed of the line. The traditional double-ended fault location method was improved and achieved certain results. However, in principle, based on the arrival time of traveling waves The method of fault section judgment and fault location will definitely be affected by the synchronization of measuring equipment and the accuracy of traveling wave velocity, and these two are uncontrollable, and their errors will definitely affect the reliability of section judgment and positioning accuracy

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