Non-Destructive Monitoring Technology for Grounding Grid Corrosion During Substation Construction

As substation construction scales up, structural damage and early-stage corrosion of grounding grids during the construction phase pose potential threats to electrical safety, highlighting the need to establish a high-precision non-destructive monitoring system during this hidden engineering stage. Focusing on the mechanisms of mechanical disturbance and stray current interference during construction, this paper proposes a collaborative detection method integrating embedded electrochemical linear polarization monitoring, low-frequency constant current source-based port network impedance matrix testing, and three-dimensional mapping of surface magnetic fields. By constructing node impedance fingerprints and corrosion rate inversion models, the method achieves precise identification of hidden breaks and high corrosion risk areas. Results from practical case tests demonstrate that this technology enables early warning of structural defects and corrosion hazards during the construction period, thereby improving the full-lifecycle operational reliability of the grounding system.