Study of Self-Tuning PI Controllers in a Constant Voltage Control Systemfor Doubly-fed Wind Turbines

摘要

The doubly-fed induction generator (DFIG) produces the reactive power to maintain its constant voltage operation.Firstly, the principle of the constant voltage control system for double-fed wind turbines is researched, and the influenceon DFIG terminal voltage when the wind speed changes and the grid voltage sags is analyzed. Secondly, self-tuningPI control algorithm based on BP neural network is proposed. This algorithm realizes the dynamic setting of PI parametersin the process of wind speed change and grid voltage sag, and then builds a simulation model of the system. Thesimulation results show that the constant voltage control system using the dynamic setting of PI parameters based on BPneural network has improved the stability of grid-connected voltage for doubly-fed wind turbines and reduced the responsetime in the process of wind speed change and grid voltage sag.