Disconnection fault detection method based on wide-area synchronous intelligent sensor

Abstract

The invention relates to a disconnection fault detection method based on a wide-area synchronous intelligent sensor. Three-phase current amplitude and phase periodically reported by a wide-area synchronous intelligent sensor are monitored in real time; once obvious disconnection fault characteristics occur, three-phase current waveforms of all wide-area synchronous intelligent sensors installed along a fault line with the disconnection characteristics at the current moment are called, automatic verification and confirmation are carried out, and finally a disconnection fault is detected and positioned. The method solves the problems of disconnection fault detection and positioning of the power distribution network at present.

Description

technical field [0001] The invention belongs to the field of electronic technology, and in particular relates to a method for detecting a disconnection fault based on a wide-area synchronous intelligent sensor. Background technique [0002] With the rapid development of the national economy, the scale of the power system is also growing, the network structure is becoming more and more complex, and users have higher and higher requirements for the stability of power supply, all of which require continuous upgrading of the power system. Avoid faults during system operation. Even if a fault occurs, it is necessary to quickly and accurately find the location of the fault after the fault occurs, and then quickly eliminate the fault to ensure the safe operation of the power system and minimize losses. [0003] In recent years, due to meteorological disasters, line aging and external damage, etc., disconnection faults are frequently occurring. The disconnection fault will cause th...

AI Technical Summary

Problems solved by technology

[0009] 1) The signal characteristics are weak and difficult to start

[0010] The wave-recording type fault indicator uses electric field mutation as the starting element of the ground fault. When a high-resistance or ground fault occurs, it is difficult to start the fault alarm because of the weak change of the three-phase voltage; the small current line selection device uses zero-sequence voltage as the starting element, Also because the zero sequence voltage changes weakly, it is difficult to trigger the fault alarm

[0011] 2) Synchronization accuracy is too low

[0012] The three-phase synchronization accuracy of the wave-recording fault indicator is very low, close to 100 microseconds, and the error of the synthesized zero-sequence current and negative-sequence current is too large to be used for accurate judgment of disconnection characteristics

[0013] 3) Local signals are used, and the information is incomplete

[0014] The small-current line selection device started by zero-sequence voltage mutation and the transient recording type fault indicator based on electric field mutation all use local signals, and use the zero-sequence power direction of a single point to select and locate lines, and cannot use wide-area information to achieve fault location, the accuracy rate is not high

[0015] Therefore, although new ground fault location technologies have emerged in an endless stream over the years, the detection and location of ground faults in distribution network interruptions is still a difficult problem that has not been well solved.

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