Design of a Grid-Connected Multiphase Servo System Without DC-Link Capacitor

Abstract

In this paper, a direct grid-connected servo system without de-link capacitor is proposed for multi-phase machines. First, the space current vector control and field oriented control are performed for the direct grid-connected multi-phase servo system. Second, the vector coordination under non-constant de-link voltage is introduced to ensure the safe current commutation. Moreover, the torque and harmonic current control are implemented independently with vector space decomposition. Finally, the experimental results are given to verify the effectiveness and validity of the proposed servo system.