Simulation and optimization of an eddy current position sensor

Position measurement is a major topic for the control of nearly every moving or rotating device. The demand for reliable and affordable position measurement systems is high. This paper presents the design of an eddy current position sensor and explains the working principle, which is based on injection locking of coupled oscillators. Thereby, the stability and the characteristic of the sensor are dependent on the combination of the used components. To investigate the complex dependency of the parameters, a single-axis sensor was analyzed by a coupled magnetic 2D finite element and an analog electronic simulation. To achieve a stable operation, a high linearity and a high sensitivity an optimization of the sensor was conducted. The suitability of the simulation results were verified by measurements on an implemented sensor.