Impact of axial and radial rotor offset on the measurement error of a capacitive angular-position sensor with modified front-end topology

This paper presents the impact of the radial and axial rotor offset on the measurement error of a capacitive angular-position sensor with a modified topology. A large radial offset, when fringing fields cannot be neglected is observed. The sensitivity of rotor offset on the measurement error is decreased by a calibration. Simulations are used to confirm the influence of fringing fields and to show the effects of calibration methods on the measurement error. The measurements showed asymmetrical measurement error versus the rotor offset, caused by the modified front-end topology. Both simulations and measurements showed decreased sensitivity of the rotor offset on the measurement error when calibration was used.