Circuit single-end ranging method based on phase aberration characteristic of positioning function

Abstract

The invention belongs to the technical field of power system relay protection, and discloses a circuit single-end ranging method based on phase aberration characteristic of positioning function. The method deduces an operating voltage of reference positions and a fault point voltage based on distribution parameters by using electric quantity of a single end, and constructs a positioning function. When the reference positions are positioned on the left side and the right side of fault point, the positioning function has different phase characteristics; and when the reference positions are changed in front and back of the fault point, the phase of the positioning function has a unique stepped aberration. A circuit is subjected to N equal distribution, the equal distribution area containing the fault point is determined by using the phase characteristics, the step length is further reduced to determine the phase aberration position in the area, and then quick fault positioning of the single end can be realized. The method overcomes the defects of the traditional single-end ranging method, and theoretically is not affected by the factors such as distributed capacitance, transition resistance, opposite side running mode, communication facilities, load current and the like. The algorithm is simple, reliable and easy to realize, and the use value of the method is strong.

Description

technical field [0001] The invention relates to the technical field of electric power system relay protection, in particular to a single-end fault distance measurement method of a line using the phase mutation characteristic of a positioning function. Background technique [0002] High-voltage transmission lines are responsible for the important task of power transmission. The terrain they pass is complex, and the probability of failure is very high, which seriously threatens the safe operation of the power grid. At present, China's voltage level is developing from 500kV to 1000kV, and the transmission capacity is increasing, so its safety and stability are particularly important. When a fault occurs, quickly finding out the cause and quickly eliminating line faults are important measures to ensure reliable power supply. Accurate fault location is the premise of troubleshooting and an important basis for finding fault points on transmission lines. It has important economic b...

AI Technical Summary

Problems solved by technology

The traveling wave method utilizes the transmission properties of fault transient traveling waves for distance measurement. It has high precision and is not affected by the operation mode and excessive resistance. application

The impedance method uses the voltage and current after the fault to calculate the impedance of the fault loop, and performs distance measurement according to the characteristic that the length of the line is proportional to the impedance. It is simple and reliable, but it is affected by factors such as the transition resistance of the fault and the incomplete symmetry of the line.

Due to the influence of the distributed capacitance of the high-voltage transmission line, there are large errors when the single-ended impedance method is applied to the fault location of the high-voltage transmission line. application requirements

Single-ended impedance method based on lumped parameters cannot be directly applied to fault location of high-voltage transmission lines

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