Research on eccentricity performance of winding wire capacitance rod position measurement sensor.

• A capacitance rod position measurement sensor with protection electrode for measuring grounding metal rod is proposed. • The finite element model of the sensor is established, the static characteristic experiment of the sensor is carried out to verify the finite element model. • The sensor is optimized, the maximum eccentricity error can be reduced from 664.96 mm to 6.36 mm. • It can realize the rod position measurement without losing step in NHR. Control rod step and scram measurement is performed by control rod position measurement sensor. For winding wire capacitance rod position measurement sensor, the static experiments were carried out and the sensor sensitivity was obtained, the finite element model was established and the results of the model were verified by experiment. The influence of wire pitch, winding method and wire number on the eccentricity performance was analyzed, and the design method of installing grounding protection electrodes was proposed. The optimized combination of parameters of the sensor was obtained. The results show that increasing wire pitch, evenly arranging the wires into two electrodes when the wire pitch is fixed, and reducing the wire number are helpful to reduce the maximum eccentricity error. Furthermore, the maximum eccentricity error can be greatly reduced by adding protection electrodes, and the optimized design can meet the requirement of rod position measurement without losing step. [ABSTRACT FROM AUTHOR]