Method for positioning transmission line fault based on power frequency phasor

Abstract

The invention relates to a method for positioning transmission line fault based on power frequency phasor, which comprises the following steps: confirming a characteristic impedance of propagation constant line according to a distribution parameter model of the transmission line; measuring the voltage Un and current In at tail end N of the transmission line by measuring the voltage Um and current Im at the starting end M of the transmission line, wherein DL is the actual length of transmission line; and calculating a distance DMf between the starting end M of the transmission line and the fault point according to the formula: DmF is equal to [th-1(BJ/AJ)]/gammaJ, thereby increasing the precision of positioning the transmission line fault.

Description

1. Technical field The invention relates to a method for locating a fault point of a transmission line based on a power frequency phasor, and is especially applicable to a method for locating a fault point of a long-distance transmission line. 2. Background technology Ensuring that the transmission line is fault-free is an important part of ensuring the transmission of electric energy. Therefore, it is an important method to determine the location of the fault point of the transmission line. Quickly and accurately determining the location of the fault point of the power line can speed up the repair of permanent faults and timely Eliminating hidden dangers to avoid the recurrence of a large number of transient faults is of great significance to ensure the safety, stability and economical operation of the power system. Generally, overhead power lines with a length of more than 300km and cable power lines with a length of more than 100km are called long lines. Leakage conduct...

AI Technical Summary

Problems solved by technology

Generally, overhead power lines with a length of more than 300 km and cable power lines with a length of more than 100 km are called long lines. Leakage conductance and capacitance cannot be ignored, then the current along the wires is different, the resistance and inductance of the wires cannot be considered according to the centralized parameters, so the voltages between the wires are also different, and the conductance and capacitance between the wires cannot be calculated according to the centralized parameters. Considering the parameters, the accuracy of judging the fault point is not high. Using the principle of double-ended traveling waves can automatically give the location of the fault point online, but the timing system and the given line length will affect the distance measurement result, and the fault judgment for long-distance transmission lines The accuracy of the point is not high, and the equipment used is expensive