Abstract
A speed regulation method with passivity-based control (PBC) for a linear direct-drive AC servo system is presented. The friction and force ripple are effectively minimized by designing a feedback controller with adaptability. Simulation verifies that the proposed control scheme not only suppresses the friction and force ripple problem of permanent-magnet linear synchronous motor (LPMSM), but also makes the direct-drive system with strong robustness to parameter variations and external disturbances.