Grounding fault detecting method, system and storage medium based on steady state fault quantity

A ground fault and detection method technology, applied in fault location, fault detection according to conductor type, measurement of electricity, etc., can solve the problems of difficulty in locating the starting time of the data window, weak transient signal, and difficulty in starting the fault, and achieves good results. The application prospect, the effect of weak dependence
CN109507516AInactive Publication Date: 2019-03-22GUODIAN NANJING AUTOMATION SOFTWARE ENG
11 Cites 9 Cited by

Patent Information

Authority / Receiving Office
CN · China
Current Assignee / Owner
GUODIAN NANJING AUTOMATION SOFTWARE ENG
Publication Date
2019-03-22
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

The invention discloses a grounding fault detecting method based on a steady state fault quantity. The method comprises the following steps: collecting a three-phase voltage, a zero-sequence voltage and a zero-sequence current of a system to be detected; comparing whether the zero-sequence voltage is greater than a starting threshold value of the zero-sequence voltage, if so, judging that a single-phase grounding fault occurs in the system; if the single-phase grounding fault occurs, comparing a size of the three-phase voltage, judging that a lagging phase of a maximum voltage phase is a faultphase, and calculating an amplitude value and a phase of a fault phase voltage at this moment and an amplitude value and a phase of the zero-sequence current; comparing sizes of the fault phase voltage and a high-resistance grounding voltage threshold value, if the fault phase voltage is greater than the high-resistance grounding voltage threshold value, judging that a high-resistance grounding fault occurs, and according to a phase relation of the fault phase voltage and the zero-sequence current, judging whether a single-phase high-resistance grounding fault occurs in the circuit. The method is weak in dependence to a fault starting moment, and capable of completing single-phase high-resistance grounding fault detection of an isolated neutral system.
Need to check novelty before this filing date? Find Prior Art

Description

technical field

[0001] The invention belongs to the technical field of relay protection, in particular to a single-phase high-resistance grounding fault detection method of a distribution network. Background technique

[0002] Most of the current distribution network systems are mainly based on ungrounded neutral points or grounded through arc suppression coils. Although single-phase ground faults do not constitute a zero-sequence current loop, the fault steady-state current is small, but with the increase of fault phase voltage , may cause insulation damage, thereby affecting the safe operation of electrical equipment, and even gradually develops into a phase-to-phase short circuit that leads to the expansion of the accident. Therefore, it is required to be able to accurately identify the faulty line and complete reliable grounding line selection.

[0003] For non-high-impedance ground faults, the transient and steady-state signals are relatively clear, and effective fault ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More