A novel capacitive flux density sensor

The localised flux density measurements are practically limited to two methods: search coil and needle probe technique. The search coil requires drilling holes in the sample under test; therefore it is a destructive method. Needle probe technique is classified as a non-destructive technique. However, removing the coating affects the magnetic properties of the sample sharp needles introduce micro-damages to the surface of the specimen. At certain conditions, the electrical contacts between the needles and the sample could be replaced by capacitors made as pads manufactured from self-adhesive conductive tape or directly painted with conductive paint on the insulated surface of the sample. The paper presents theoretical analysis of the concept of the capacitive sensor. The simulations suggest that the described capacitive sensor would be suitable for detecting localised flux density in laminated material, especially at higher frequencies.