B-type overhead line-cable hybrid line traveling wave fault positioning method

Abstract

The invention provides a B-type overhead line-cable hybrid line traveling wave fault positioning method, which comprises the following steps of: (1) using connecting points P1 and P2 of an overhead line and a cable as boundaries, representing lengths of an overhead segment MP1, a cable segment P1P2 and an overhead segment MP P2N by using LO1, LC and LO2 respectively, representing the propagation speed of a transient state travelling wave in the overhead line and the cable by using vO and vC respectively, and calculating the time difference from an initial travelling wave surge generated at a P1 point fault to two ends of M and N of the line and the time difference from an initial travelling wave surge generated at a P2 point fault to the two ends of M and N of the line, which serve as setting values; (2) measuring an absolute moment from an initial travelling wave surge generated at a certain fault to the two ends of M and N of the line, and representing the absolute moment by using tM and tN; and (3) determining the fault point position.

Description

technical field The invention belongs to the technical field of power system protection, and in particular relates to a traveling wave fault location method for a B-type overhead wire-cable hybrid line. Background technique Quickly and accurately determining the location of the fault point of the power line can speed up the repair of permanent faults, eliminate hidden dangers in time to avoid the recurrence of a large number of transient faults, and is of great significance to ensure the safety, stability and economic operation of the power system. With the development of modern urban construction, the city's electricity load continues to increase, and the existing overhead lines can no longer meet the needs of urban development, and the criss-cross overhead lines also affect the overall image of the city. Therefore, replacing the original overhead line power supply with cable network power supply has become an inevitable trend in the development of urban power grids. With...

AI Technical Summary

Problems solved by technology

However, various single-ended and double-ended traveling wave fault location algorithms that have been proposed cannot be directly used for overhead line-cable hybrid lines.

Therefore, when a hybrid line fails, it often takes more time than ordinary overhead lines to find and repair the fault, which seriously affects the power supply reliability of the hybrid line

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