Hybrid Grid Forming/Following Reconfiguration Converter Architecture for DFIG

The power system, characterized by a high proportion of renewable energy sources, faces challenges in terms of stability due to the lack of damping and inertial support provided by synchronous machines. This poses challenges to the safe and stable operation of traditional grid-following Doubly Fed Induction Generators (DFIGs). This paper proposes a hybrid grid-forming/following reconfiguration converter architecture for DFIGs. Unlike conventional methods that rely on Phase Locked Loop (PLL) synchronization, this architecture utilizes grid control technology to control the Superconducting Magnetic Energy Storage (SMES) system parallel to the DC side of the DFIG. During the fault period, the grid-side converter switches from parallel mode to series mode, dynamically emitting reactive current as per the control target. Simulation results indicate that the proposed scheme is more effective in providing frequency and voltage support to the power grid during faults compared to the traditional grid-following DFIG.