Method for starting recloser of extra high-voltage transmission line

Abstract

The invention provides a method for starting a recloser of an extra high-voltage transmission line, which is applied to an extra high-voltage transmission line with a fault current limiter. The method comprises the following steps: firstly, judging whether measurement impedance is larger than xZ1 or not to determine the position of a fault; if so, determining that the fault occurs on the transmission line, allowing to start the recloser, and otherwise, determining that the fault occurs in the fault current limiter, and needing to further judge whether a bypass switch of the fault current limiter is closed or not, namely judging whether the fault current limiter stops operating completely or not; and if so, allowing to start the recloser, and otherwise, forbidding starting the recloser. The method for starting the recloser can prevent the recloser from being started under the condition that internal elements of the fault current limiter are damaged, thereby preventing the extra high-voltage transmission line from being impacted.

Description

technical field [0001] The invention relates to a reclosing starting method of an ultra-high voltage transmission line, in particular to a reclosing starting method applied to an ultra-high voltage fault current limiter. Background technique [0002] In order to limit the short-circuit current generated when a short-circuit fault occurs in the current system, the East China Power Grid is currently preparing to install a resonant fault current limiter (FCL) on the ultra-high voltage transmission line. The principle of the resonant fault current limiter is as follows figure 1 As shown, when the transmission line is operating normally, switch B 1 disconnected from the thyristor valve T, the inductor L 1 Series resonance occurs with capacitor C, at this time the equivalent impedance of the fault current limiter is 0; when a short-circuit fault occurs on the transmission line, switch B 1 Conducted with the thyristor valve T, the capacitor C is bypassed, and the equivalent imped...

AI Technical Summary

Problems solved by technology

However, if the fault occurs on primary equipment such as reactors, capacitors, and thyristors inside the fault current limiter, it is generally a permanent fault

At this time, the use of automatic reclosing will cause another impact on the system, which will not only fail to improve the suspension stability of the system, but may also cause equipment damage

However, the automatic recloser in the traditional protection device cannot judge the location of the fault, and needs to be improved

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