Research on the Detection Technology for Scale Layer on Equalizing Electrode in the Converter Valve Cooling System Based on Optical Method

The equalizing electrode is a key component of the converter valve. Aiming at the problem of monitoring the fouling conditions of them, a non-contact detection method based on the infrared light transmittance characteristics of polyvinylidene fluoride (PVDF) material is proposed. By screening the suitable infrared wavelength (940 nm), an infrared optical detection device integrating light source control, optical imaging, and image processing modules was designed. The device adopts a 45-degree reflector and a compact structure design, which improves the flexibility and applicability in limited spaces. During the annual inspection of Baoji Converter Station, a field detection validation was conducted, achieving a test accuracy of 0.1 mm with an error controlled within $\pm 5 \%$.