Double-sampling rate distribution network line fault point positioning method based on traveling wave method

Abstract

The invention discloses a double-sampling rate distribution network line fault point accurate positioning method based on a traveling wave method. The method is characterized by carrying out phase correlation calculation on a phase current waveform collected by a low sampling rate measuring device; when a fault is determined to generate, starting a wave recording function of a high sampling rate measuring device; and then, processing the phase current waveform collected by the high sampling measuring device, and carrying out accurate positioning of fault points according to a D-type travelingwave method. An unreliable problem of traditional amplitude triggering wave recording is solved through carrying out correlation coefficient calculation on waveform data. The correlation calculation is only performed on low sampling rate data, which effectively reduces a calculation amount and improves a fault wave recording triggering speed. Simultaneously, the adopted high sampling rate measuring device has a small sampling time window and does not depend on a large storage capacity so as to effectively reduce cost of a distribution network detecting device.

Description

technical field [0001] The invention relates to a fault diagnosis method for a distribution network line, in particular to a method for locating a fault point of a distribution network line with a double sampling rate based on a traveling wave method. Background technique [0002] With the continuous development of the economy, users have increasingly higher requirements on the quality of power supply. As the part of the power grid that directly interacts with users, the distribution network has a major impact on the user's power consumption experience, and the fault location of the distribution network is particularly important. At present, the domestic distribution network mostly adopts the neutral point non-effective grounding method, the topology structure is complex, and there are many branches; the ground fault current is small, and the fault location is difficult. With the improvement of people's requirements for distribution network automation level, it is more urge...

AI Technical Summary

Problems solved by technology

However, the complex line structure and numerous branches of the distribution network lead to small fault traveling wave amplitude and large attenuation distortion, which makes it difficult to locate distribution network faults.

However, the current fault traveling wave detection device usually uses the traveling wave amplitude as the fault criterion, which leads to misjudgment and missed judgment of the fault, and it is difficult to obtain a better fault traveling wave recording waveform; The sampling rate of the equipment is high, and the hardware performance of the equipment is high, and it is not widely used in the case of low-cost control of the distribution network

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