Non-effective earthing distribution system fault locating method based on neutral point of transient traveling wave

Abstract

The invention discloses a method for locating fault of power distribution system with ineffectively grounded neutral point based on transient traveling wave, which can acquire required traveling wave signals and relatively higher detection reliability by arranging equipment only on both sides of circuit. According to the actual site condition, a non-contact electromagnetic field sensor is arranged in a transformer substation to acquire transient voltage and current traveling wave, a power distribution transformer arranged on the tail end of the circuit transmits voltage-variable traveling wave to solve the problem in acquisition of tail-end voltage traveling wave signals, and the type of the fault of the circuit can be rapidly recognized according to the amplitude and the polarity characteristics of a fault traveling wave recorded by the secondary side of the transformer. The invention provides a new fault search algorithm based on the midpoint of time to solve the problem of noncontinuous wave speed of aerial wire and cable. Accordingly, the proposal can achieve the assembly and the operation of the equipment without adding extra primary equipment of the system and powering off the circuit, thus saving the cost and reducing the complex degree of the project. Practical operation shows that the method can locate a fault within a range of plus or minus 100 m.

Description

technical field [0001] The invention relates to a fault location method based on the principle of traveling wave distance measurement when various types of faults occur in distribution system lines in the neutral point non-effective grounding operation mode of the power system, in particular to a single-phase grounding method for a neutral point non-effective grounding system Automatic fault location method. Background technique [0002] Whether and in what form the neutral point of the power system is grounded is a comprehensive issue involving many aspects such as technology, economy, and safety. The current processing methods mainly include: direct grounding, reactance grounding, low resistance grounding, high resistance grounding, arc suppression coil grounding (also known as resonance grounding) and no grounding. The first three are called large current grounding systems, and the latter three are called small current grounding systems. [0003] my country's medium-vol...

AI Technical Summary

Problems solved by technology

[0022] The technical problem to be solved by the present invention is to provide a fault location method for non-effectively grounded neutral point distribution system based on transient traveling waves, so as to solve the technical problem of difficult fault location of distribution lines

Images