Modeling and Fabrication of Low-Cost Transformer Inductive Conductivity Sensors

The conductivity of seawater can be used to estimate its salinity in practical measurements. Unlike electrode-based conductivity sensors, transformer-type inductive conductivity sensors (TICS) provide superior corrosion resistance, making them particularly suitable for long-term ocean observation. In this study, the effects of core material, number of turns, current, and coil spacing on sensor performance were investigated using COMSOL Multiphysics. Based on the optimized parameters—an inner radius of 12.05 mm, an outer radius of 23.6 mm, a height of 18.8 mm, 10 turns for the drive coil, and 105 turns for the sensing coil—TICS prototypes were fabricated. The fabricated sensors demonstrated reliable operation in saline conditions with a high concentration of 80 g/L and achieved a high sensitivity of 3.35. A better understanding of the performance and characteristics of TICS will enable the development of high-quality, low-cost sensors for practical applications., high-quality sensors will be created based on our study.