How X-Ray Imaging Improves Grid Equipment Diagnostics

With continuous advancements in power grid equipment research and manufacturing, an increasing number of new devices are being deployed into power systems. Effective monitoring of in-service equipment has therefore become critically important. The introduction and successful application of X-ray digital imaging technologies (Computed Radiography - CR, Digital Radiography - DR) in the power sector have provided an accurate, intuitive, and innovative method for condition-based maintenance and assessment of power equipment.

Using X-rays to image the internal structure of electrical equipment overcomes the limitations of traditional methods, which rely solely on indirect analysis of routine test data and cannot visually reveal internal faults. Implementing non-destructive X-ray inspection on energized grid equipment significantly reduces maintenance time and avoids major economic losses caused by equipment disassembly and unplanned outages. Moreover, image analysis clearly reveals internal structures, offering strong support for accurately diagnosing internal equipment failures.

Currently, X-ray technology has certain limitations. For example, a portable X-ray unit with a maximum output of 300kV can penetrate steel up to approximately 55mm thick. For power equipment with complex or large cross-sectional structures, existing portable X-ray systems may not achieve effective imaging. Additionally, areas with confined spaces where the X-ray source cannot be properly positioned also remain inaccessible for inspection.

Common switchgear abnormalities detectable by X-ray imaging include:

Internal Foreign Objects
Loose bolts, debris from mechanical wear during switching operations, or foreign materials introduced during installation can all pose serious safety risks to high-voltage switchgear.

Missing Components Due to Manufacturing or Installation Errors
High-voltage circuit breakers and GIS contain numerous internal parts. If any component is accidentally omitted during assembly, it could lead to operational hazards at the site.

Assembly Misalignment
Improper alignment of contacts in circuit breakers or disconnectors during production significantly impacts operational reliability. Poor alignment may cause contact deformation or rod fracture during operation, leading to discharge and catastrophic equipment failure.

Beyond these common issues, X-ray inspection holds broad application potential in the power industry. When combined with experienced fault diagnosis, accumulated inspection data, and AI algorithms, it is expected to deliver even greater value in future smart grid applications.