Online Inductance Identification Method for Dual Three-phase PMSG of Wind Turbines

In this article, an online inductance identification method applied to dual three-phase permanent magnet synchronous generator (DTP-PMSG) is proposed. Based on the proposed method, the self-inductance and mutual inductance can be obtained in real time. Firstly, the physical model of DTP-PMSG is investigated, where the cross-coupling characteristics of the inductance is analyzed. Then, an inductance identification strategy based on the rotation signal injection under a single three-phase winding is proposed. In order to improve the robustness of the proposed method, the composite filter system is designed to achieve the signal processing in the inductance identification. The self-inductance and mutual inductance can be finally obtained based on the extracted high-frequency signal in the dual three-phase windings. For improving the identification accuracy, the inverter nonlinearity effect and the digital delay effect are analyzed and compensated. The effectiveness of the proposed method is verified by the experimental results.