Controller design for a permanent magnet linear synchronous motor: A singular perturbation method

This paper considers the design problem of a three-closed-loop controller for a permanent magnet linear synchronous motor. Taking into account the multiple time-scale property of the system, the design is achieved in two stages. In the first one, the inner loop (current-loop) controller is designed based on the singular perturbation theory and pole assignment technique. The controller gains can be constructed by solving a set of well-defined linear matrix inequalities. In the second stage, with the obtained controller gains, a homotopy algorithm is formulated to design the velocity- and position-loop controllers simultaneously. Simulation is given to illustrate the proposed results.