A combined control strategy of wind energy conversion system with direct-driven PMSG

摘要

Due to the frequent changes of the operating point right across the whole operation range, industrial processes are generally nonlinear. There exists a large amount of physics constraints in a permanent magnet synchronous generator (PMSG) based Wind Energy Conversion System (WECS). The control problems of the constrained nonlinear processes present great challenge. Considering the various disturbances, including the internal disturbances, i.e., system uncertainties and the modeling errors, and the external disturbances, i.e., the unknown external forces and wind speeds. A compound control combined with Model Predictive Control (MPC) theory and Disturbance Observer (DO) is proposed in this paper. MPC can roll optimization and feedback correction. Therefore, the model predictive control can achieve very high control performance. In addition, to reduce prediction error caused by parameter variation during operations, the DO is adopted to estimate a lumped disturbance term that is feed-forward then. Finally, the simulation results show that the proposed composite control strategy has a good speed tracking performance in a wind energy conversion system.