Mixed modulus time domain fault positioning method for identical-tower double-loop direct current line

Abstract

The invention discloses a mixed modulus time domain fault positioning method for an identical-tower double-loop direct current line. The method comprises the following steps that 1, a phase-mode transformation matrix is constructed through an impedance matrix and an admittance matrix, and a voltage decoupling matrix and a current decoupling matrix are built; 2, according to the obtained voltage decoupling matrix and the current decoupling matrix, the voltage and the current obtained at the two ends of the line are subjected to decoupling conversion, each modulus voltage and modulus current of the identical-tower double-loop direct current line are worked out, and the line modulus voltage component and the line modulus current component are extracted; 3, the way-side voltage distribution at the two ends of the line is calculated; 4, the fault positioning criterion based on the mixed modulus is constructed. The mixed modulus time domain fault positioning method has the advantages that the fault positioning precision is high, the reliability is high, the calculation quantity is small, the realization is easy, and the like.

Description

technical field [0001] The invention relates to a fault location method for a double-circuit direct current transmission line on the same tower, in particular to a mixed-modulus time-domain fault location method for a double-circuit direct current transmission line on the same tower. Background technique [0002] Compared with high-voltage AC transmission, high-voltage direct current transmission has the advantages of large transmission capacity, flexible and rapid control, and no synchronization and stability problems. With the continuous development of the economy, land resources are becoming more and more tense, which leads to an increase in the construction cost of the transmission network. The double-circuit DC transmission line on the same tower has the characteristics of small transmission corridor and fast construction speed, which can effectively alleviate the above contradictions and have significant economic and social benefits. Therefore, it has attracted extensi...

AI Technical Summary

Problems solved by technology

However, the current fault location methods for DC lines are limited to single-circuit DC lines, and are based on the basic premise that the transmission line is a symmetrical structure.

However, for double-circuit DC transmission lines on the same tower, the fault electromagnetic coupling characteristics of double-circuit DC transmission lines on the same tower are very complicated due to the existence of line-to-line coupling and phase-to-phase coupling at the same time; The tower double-circuit DC line does not adopt symmetrical transposition measures, that is, the line cannot be simply treated as a balanced line

Therefore, the existing phase-mode transformation method and fault location algorithm for single-circuit DC transmission lines are no longer applicable to double-circuit DC lines on the same tower, and it is urgent to study the applicable fault location method according to the characteristics of double-circuit DC transmission lines on the same tower

Images