State of the art of control techniques for direct-drive linear motion systems with tubular linear permanent-magnet motors

The paper compares control strategies for tubular linear permanent-magnet motors with the aim of assessing their performances in terms of dynamic performances and accuracy. The well known attractiveness of this motor is represented by its use in servo applications, with high speed and especially high precision positioning systems. The paper focuses on control techniques for direct-drive systems using tubular linear permanent-magnet motors, providing a review of electronic supply and control techniques. Finally, a Direct Thrust-Force Control strategy for a two-phase tubular linear permanent-magnet motor prototype is introduced, discussing electric supply, inverter topologies, applicability. Implementation of control techniques in dSPACE-based Hardware-in-the-Loop simulators for the embodied Direct Thrust-Force Control strategy in real time direct-drive systems confirms its applicability, highlighting the most important features of operation.