Method for judging voltage compensation of single-pole adaptive reclosure of electric transmission line

Abstract

The invention discloses a method for judging the voltage compensation of a single-pole adaptive reclosure of an electric transmission line, which comprises the following steps of: 1) defining a fault phase through a phase selecting component in a line protecting device; 2) computing a computation fault phase terminal voltage value when having the temporary fault under the current system running state through a temporary fault model, and subtracting a practically-measured practical fault phase terminal voltage value to obtain a differential value; 3) judging to be a temporary fault and exporting the reclosure if the differential value computed in the step 2) is less than a set value; and 4) judging to be a permanent fault and not overlapping the reclosure if the differential value computed in the step 2) is larger than the set value. By setting the temporary fault model, and judging the temporary fault and the permanent fault with the differential value between the computation fault phase terminal voltage value and the practical fault phase terminal voltage value, the method can judge the property of the fault only with single terminal quantity without opposite-side information.

Description

technical field [0001] The invention relates to the field of relay protection for power system transmission lines, in particular to a single-phase automatic reclosing control method for transmission lines without shunt reactors. Background technique [0002] Automatic reclosing technology is one of the important measures to ensure the safe power supply and stable operation of the power system. Since most of the faults on ultra-high voltage transmission lines are transient faults, putting the line back into operation after the fault is eliminated can effectively improve the stability of the power system and the quality of power supply to users, so the automatic reclosing technology is currently widely used in power systems. Among all kinds of faults in power lines, single-phase grounding faults account for more than 80%. Therefore, it is of great practical significance to study single-phase automatic reclosing technology. However, the current single-phase automatic reclosin...

AI Technical Summary

Problems solved by technology

The voltage discrimination method uses the characteristics of capacitive coupling voltage to distinguish between transient faults and permanent faults. Its sensitivity is related to transition resistance and line length. Due to the influence of electromagnetic coupling voltage, there is a possibility of misjudgment in the voltage discrimination method.

For transmission lines with shunt reactors, due to the influence of shunt reactors, the electrical quantities on the disconnected phases have beat frequency characteristics, and there is a possibility of misjudgment by using the voltage discrimination method and the current discrimination method.

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