Position estimation for linear electromagnetic actuators

Abstract

This paper explores the possibilities of position estimation for linear electromagnetic actuators, in comparison to rotating electric motors. The linear actuator under study is a DC type short stroke permanent magnet actuator with an E-core stator. The non-linearity in the inductance model is first measured and identified on a commercially available actuator, after which a demodulation scheme, inspired from sensorless control methods applied to rotating electrical machines, is designed to estimate the position of the mover. The estimation scheme is validated by simulation results at the end.