Virtual Synchronous Control Based on Control Winding Orientation for Brushless Doubly Fed Induction Generator (BDFIG) Wind Turbines Under Symmetrical Grid Faults

Abstract

The Brushless Doubly Fed Induction Generator (BDFIG) has huge potential for wind power systems due to its high reliability and low maintenance cost. To add inertia for system stability enhancement, as well as to maintain the uninterrupted operation during symmetrical grid faults, this study proposes a Virtual Synchronous Control (VSC) with a transient current compensation strategy for BDFIG. The proposed VSC is realized by regulating the virtual inner electrical potential and angular velocity of BDFIG under Control Winding (CW) current oriented vector control, and compensating for the transient CW current to weaken the transient inner electrical potential under symmetrical grid faults. Modeling and analysis of such a VSC strategy are presented in this paper, and a simulation is also made to compare the performances of existing and proposed VSC strategies. It is shown that the merits of the proposed VSC can enhance the fault ride through the ability of the BDFIG system and support the recovery of grid voltage.