Method for setting reclosing time on basis of secondary arc currents and recovery voltages

Abstract

The invention discloses a method for setting the reclosing time on the basis of secondary arc currents and recovery voltages. The method includes judging types of single-phase earth faults when the single-phase earth faults of double-circuit lines of the same towers occur; computing numerical values of the secondary arc currents and the recovery voltages by the aid of the types of the single-phase earth faults, selecting the appropriate reclosing time and switching the reclosing time of the double-circuit lines of the same towers to the reclosing time corresponding to the current fault types. The secondary arc currents and the recovery voltages correspond to the current fault types. The method has the advantages that the corresponding reclosing time can be selected according to the types of the specific single-phase earth faults of the power transmission lines and can be changed along with running conditions of the power transmission lines instead of being fixed, accordingly, the optimal reclosing time can be selected when the running conditions of the ultrahigh-voltage double-circuit lines of the same towers are different, the problem of reclosing failures during temporary faults can be effectively solved, and the single-phase automatic reclosing success rate can be increased.

Description

technical field [0001] The invention relates to the technology of power transmission and transformation equipment, in particular to a reclosing time setting method based on latent power supply current and recovery voltage. Background technique [0002] According to the operation experience of my country's power grid, in the 220kV and above high-voltage power grid, single-phase ground faults account for more than 80%, and most of them are instantaneous faults, and the success rate of single-phase reclosing is more than 80%. Therefore, as an effective measure to ensure safe power supply and stable operation of the system, single-phase automatic reclosing has been widely used in high-voltage power grids. [0003] However, when a single-phase ground fault occurs in the power grid and the fault phase is removed, due to the coupling effect of the interphase capacitance and mutual inductance, a certain value of ground current still flows through the fault point of the fault phase, ...

AI Technical Summary

Problems solved by technology

However, there are few studies on medium-, long-distance and short-distance lines erected without transposition, which cannot provide sufficient technical support for reasonable setting of reclosing time

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