Check patentability & draft patents in minutes with Patsnap Eureka AI!

Method for precisely selecting single-phase earth faulty line for system with non-effectively earthed neutral point

A non-effective grounding and line selection method, applied in the direction of the fault location, etc., can solve the problems of small applicable occasions, single-phase grounding fault handling problems have not been well resolved, and the complex structure of the distribution network

Inactive Publication Date: 2009-10-21
曲娜
View PDF0 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0002] Because the neutral point ungrounded system has a series of advantages, it is widely used in my country's medium and high voltage power grids. However, its single-phase ground fault handling problem has not been well resolved. With the development of power systems, the reliability of power grids requires Due to the extremely complex structure of the distribution network and the great difference in line length, the previous line selection methods can only work in specific environments, the applicable occasions are small, and the accuracy of line selection is very low

Method used

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
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for precisely selecting single-phase earth faulty line for system with non-effectively earthed neutral point
  • Method for precisely selecting single-phase earth faulty line for system with non-effectively earthed neutral point
  • Method for precisely selecting single-phase earth faulty line for system with non-effectively earthed neutral point

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0013] Combine now figure 1 , figure 2 , image 3 , give a specific implementation.

[0014] When the system is running normally, the entire line selection system is in a stable state. At this time, the discharge capacitor 9 is in the state of charging completion, and the controllable switch 4 is disconnected. SCR A is shown in Figure 11, SCR B is shown in Figure 12, and SCR B is shown in Figure 12. 13 is off. When the grounding point diagram 111 appears on phase C, zero-sequence voltage appears. At this time, the control unit analyzes the zero-sequence current of each branch collected at this time. When the polarity is opposite to branch 2 in Fig. 17 and branch 3 in Fig. 18, it can be preliminarily judged that branch 1 in Fig. 16 is a fault line. When the grounding current is stable (if there is an arc suppression coil in the system, you need to wait until the arc suppression coil action is completed), the SCR A connected to the fault is triggered to conduct, forming a h...

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

PUM

No PUM Login to View More

Abstract

The invention discloses a method for precisely selecting a single-phase earth faulty line for a system with a non-effectively earthed neutral point based on transient signal analysis and externally input DC pulse signal analysis. The method comprises the following steps: firstly, initial judgment is conducted to an earth line by analyzing a distributed capacitance momentary discharge signal generated by an earthed circuit branch; and then high-voltage DC pulse current is input into an earth phase, thereby precisely selecting the faulty line. The method pertains to the field of electric system fault diagnosis. The method uses a DC pulse signal input unit and a control judging unit. When the control judging unit finds out the residual voltage of the system exceeds a threshold value, the whole system is started; firstly, the stored distributed capacitance discharge signal is analyzed and then the DC pulse signal input into a fault phase is analyzed; therefore, the method can precisely find out the earth faulty line without being affected by an extinction coil.

Description

Technical field: [0001] An accurate line selection method for a single-phase ground fault in a neutral point non-effectively grounded system, which consists of two steps: 1. Analyze the transient discharge current of distributed capacitance at the moment of grounding; 2. Analyze the high-voltage direct current injected into the fault phase through an external high-voltage capacitor Pulse current. Thus, the fault line is obtained. It belongs to the category of power system fault diagnosis. Background technique: [0002] Because the neutral point ungrounded system has a series of advantages, it is widely used in my country's medium and high voltage power grids. However, its single-phase ground fault handling problem has not been well resolved. With the development of power systems, the reliability of power grids requires Due to the extremely complex structure of the distribution network and the great difference in line length, the previous line selection methods can only work...

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

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G01R31/08
Inventor 曲娜
Owner 曲娜
Features
  • R&D
  • Intellectual Property
  • Life Sciences
  • Materials
  • Tech Scout
Why Patsnap Eureka
  • Unparalleled Data Quality
  • Higher Quality Content
  • 60% Fewer Hallucinations
Social media
Patsnap Eureka Blog
Learn More

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2025 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com