Nonsynchronous fault range-finding method for double-circuit line, comprising series compensation, on same tower

Abstract

The invention discloses a nonsynchronous fault range-finding method for a double-circuit line, comprising series compensation, on the same tower, and the method comprises the steps: employing a six-sequence component method for decoupling for each sub-algorithm, and eliminating a series compensation voltage at a side nearby a fault and series compensation currents at two sides in a transmission equation according to the characteristics that the voltages, deduced from two sides, of a fault point are equal and the currents at two sides of a series compensation device meet the Kirchhoff's Current Law; constructing a fault positioning function through employing the pure resistance of a transition resistor at the fault point when the double-circuit line on the same tower comprises the series compensation; inputting double-end data into an M-side sub-algorithm and an N-side sub-algorithm at the same time for calculation, and directly achieving the precise positioning of a fault without the discrimination of a fault section. The method is applicable to all types of faults, does not need to carry out synchronous sampling, is independent of a series compensation device model, is not affected by MOV nonlinearity, does not need to know the position of the fault point relative to the series compensation in advance, is simple in range-finding principle, just needs to carry out the one-dimensional search of the fault distance, and does not have a problem of false root discrimination.

Description

technical field [0001] The invention relates to the field of electrical technology, in particular to a non-synchronous fault distance measuring method for parallel double-circuit lines on the same pole including series compensation. Background technique [0002] EHV and UHV lines equipped with series capacitor compensation devices (series compensation) have long transmission distances and are often connected to large power plants and load centers. Failure to repair faults in time may cause serious losses; series compensation capacitors generally use non-linear The metal oxide varistor (MOV) with volt-ampere characteristics is used for overvoltage protection. Due to the existence of nonlinear MOV, the conventional fault location method is no longer suitable for the double-circuit series compensation system. Therefore, there is an urgent need to study the adaptability of relay protection and fault location for double-circuit lines with series compensation on the same pole. ...

AI Technical Summary

Problems solved by technology

[0004] Many scholars at home and abroad have studied the fault location of series compensated transmission lines, but there is little research on double-circuit lines

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