Compensation of the Electrodes Skewing Error of Runout Capacitive Sensors for Hydro Generators Condition Monitoring System

In the paper presents a method for reducing the error of capacitive runout sensors, which arises due to the non-parallelism (skew) of the flat electrodes of the sensor relative to the measurement surface. The ratios of the sizes of the external and internal electrodes have been found, at which the main component of the transformation error “microdisplacement - reciprocal value of capacitance” tend towards an infinitesimal value. The effectiveness of the proposed correction method is analyzed depending on the electrode skew coefficient. It is shown that the relative measurement error at large skew angles decreases several times, and at small ones - several hundred times.