A Non-Destructive Testing Method for Fault Detection of Substation Grounding Grids
Xiujuan Wang1, Zhihong Fu2, Yao Wang3,4
1School of Electrical Engineering, Chongqing University, State Key Laboratory of Power Transmission Equipment and System Security, Chongqing 400044, China. shanshui510@163.com.
Sensors (Basel, Switzerland)
|May 5, 2019
Summary
A novel magnetic source excitation method enhances grounding grid detection. This contactless, portable technique offers superior accuracy and anti-interference for online power system safety monitoring.
Area of Science:
- Electrical Engineering
- Power Systems
- Geophysics
Background:
- Grounding grids are essential for power system safety and stability.
- Corrosive cracking degrades grounding grid performance, posing significant risks.
- Existing fault diagnosis methods have limitations in lead dependency and online detection capabilities.
Purpose of the Study:
- To propose and validate a new, non-contacting method for detecting faults and assessing the performance of grounding grids.
- To overcome the limitations of existing grounding grid diagnostic techniques.
- To provide a portable and reliable solution for online grounding grid monitoring.
Main Methods:
- Development of a portable measuring device with two horizontal excitation coils and two vertical receiving coils.
- Utilizing magnetic source excitation to detect secondary magnetic field signals.
- Extracting signals by precise coil positioning to isolate the influence of underground media.
- Analyzing the impact of factors like breakpoints, excitation frequency, and soil conditions.
Main Results:
- The proposed magnetic source excitation method demonstrates higher measurement accuracy and stronger anti-interference capabilities compared to existing methods.
- Simulations and experiments validate the effectiveness and reliability of the technique.
- The method is proven to be portable, contactless, and not limited by grounding leads, enabling online detection.
Conclusions:
- The developed method offers a precise and versatile approach for grounding grid detection and performance assessment.
- Its portability, contactless nature, and online detection capability make it highly valuable for practical engineering applications.
- This technique provides significant guidance and reference value for ensuring the integrity of power system grounding grids.
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