Transient Electromagnetic Apparent Resistivity Imaging for Break Point Diagnosis of Grounding Grids
Fu Zhihong1, Yu Cigong1, Hou Xingzhe2, Zhang Huiqing1, Qin Shanqiang1
1. State Key Laboratory of Power Transmission Equipment & System Security and New Technology Chongqing University Chongqing 400044 China; 2. Electric Power Research Institute of Chongqing Chongqing 401123 China
Abstract：This paper first proposes the transient electromagnetic method for point diagnosis of grounding grids in transformer substation to achieve nondestructive testing. When the pulse signals in transmitting coil ramp off suddenly, the induced signal in grounding grids can be detected. After apparent resistivity inversion and imaging, the break point fault can be diagnosed directly from the image. The Ansoft Maxwell software is involved to forward calculate the transient electromagnetic response signal in grounding grids. The differences between the apparent resistivity cross-section diagrams of grounding grid show that the method is feasible. The break point diagnosis experiment in transformer substation also demonstrates the effectiveness of this method. As a simple and efficient break point diagnosis method of grounding grids, it can be used in engineering practice.
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2014, Vol. 29 
