Dual Three-Level Double-Fed Induction Motor Control Based on Novel Stator Flux Observer

The vector control strategy for double-fed induction motor fed by back-to-Back dual three-level converter was studied in this paper. The accurate observer and effective control of the stator flux for double-fed induction motor has significant sense to the performance improvement of vector control system. In the thesis, two one-stage low-pass filters are adopted instead of the pure integrator in the stator flux observer, which can steady the phase and amplitude. Three-level converter with active front end (AFE) works with unity power factor and low gird side's harmonic distortions, whose energy can flow in both direction. The result of field running has demonstrated that, the solutions of the vector control strategy for double-fed induction motor has excellent control performance, truly realizing a high degree of integration between speed drives for energy saving and environmentally friendly.