Use of Inverse models built for accurate microstepping of linear switched reluctance step actuators

A microstep control strategy, developed for linear switched reluctance step actuators, is proposed in this paper. The design of the studied actuator using finite element simulations has allowed to put, especially, in evidence the important dissymmetries observed on electromagnetic force characteristics developed by the different actuator phases. From this observation, an adapted control strategy, exploiting the obtained finite element results is used for punctual evaluation of the electromagnetic force. Hence, response surfaces of electromagnetic force according to plunger positions and phase supply currents are built and inversed in order to determine the supply current configurations required for accurate microstepping. Practical tests have validated the elaborated control strategy