Alternating-current component transmission parsing method and modeling along line in operation of high-voltage direct current in different ways

Abstract

The invention relates to an alternating-current component transmission modeling and parsing method along line in operation of a high-voltage direct current in different ways. The method comprises: firstly, an impedance admittance parameter of a line with a unit length is calculated according to a direct-current line pole parameter in a direct-current project; secondly, a uniformly distributed parameter circuit of a single-loop long-distance line is processed to be equivalent to a single loop type equivalent circuit and a correlated parameter is solved; thirdly, an equivalent circuit of a positive-negative dual-loop direct-current power transmission line with the unit length in the direct-current project is decoupled by using a phase-mode transformation matrix; fourthly, a central parameter impedance value and a ground admittance value in the positive-negative dual-loop with the unit length are converted into a distributed parameter impedance value and a ground admittance value; and fifthly, with combination of the direct-current line length in the high-voltage direct-current power transmission project as well as boundary conditions in different operation ways, an operation equivalent circuit diagram of a high-voltage direct-current power transmission system is transformed to obtain alternating-current component along-line transmission and parsing models of the high-voltage direct-current power transmission system in different operation ways.

Description

technical field [0001] The invention relates to the technical field of high-voltage direct current transmission, in particular to an analysis method and modeling of transmission of an AC component along a line under different modes of high-voltage direct current operation. Background technique [0002] HVDC transmission is an effective means to solve long-distance power transmission and large power grid interconnection, and it has been widely used in my country and the world. The closing operation of the converter transformer of the DC system is the basic operation in the commissioning and production operation stages of the DC converter station, and it is also an important means to evaluate its manufacturing quality and insulation performance. In a multi-infeed AC / DC hybrid system, the no-load closing of the transformer adjacent to the DC system or the AC system, or the no-load closing of two transformers on one pole inside the DC system may cause the normal operation of the...

AI Technical Summary

Problems solved by technology

When the no-load closing transformer is put into the system, because of the saturation of the internal nonlinear iron core, an excitation inrush current dozens of times the rated current will be generated. At the same time, a complex summation inrush current will appear when the transformer is running, and the summation inrush current contains a large number of secondary Harmonic positive sequence component, through the transformation of the converter, will generate a 50Hz component on the DC line itself, and transmit and amplify it through the line, so that the DC 50Hz protection on the opposite side line will malfunction

Images