Corrosion Assessment Method of Substation Grounding Network Based on Time-Domain Pulsed Eddy Current Feature Signal Extraction

The grounding grid of a substation is crucial. To mitigate adverse effects caused by defect of grounding conductors, we propose a nondestructive method of pulsed eddy current (PEC) to assess corrosion of substation grounding grids. Firstly, from the theoretical aspect, the influence of time-domain characteristic signal of PEC response signal of grounding body corrosion is deduced, thus proposing that decay time constant (DTC) can be used for indicating degree of sample damage. Afterwards, a model to simulate is developed to validate multi-parameter time-domain characterization method for corrosion assessment, which proves the feasibility of DTC for characterizing multi-parameter changes of substation grounding networks due to corrosion.