Modeling, Simulation And Control Strategy Of The Doubly-fed Wind-power Generator System

This dissertation throughtfully studies the control system of the Doubly-fed Induction Generator (DFIG). It focuses on the the control strategies of Maximal Power Point Tracking (MPPT) and no-load cutting-in, which are two most important control strategies for the DFIG.At first, based on the mathematical model of DFIG, it analyzes the control principle of DFIG and gives out the MPPT and no-load cutting-in control strategies based on the field oriented vector control scheme. Furtheormore, it proposed an improved design method for the PI controller, which could coordinate the control strategies of rotor connected converter and grid connected converter in the wind power generation.Finally, based on the theoretical study, a model of Variable Speed Constant Frequency (VSCF) system is built using the Real Time Digital Simulator (RTDS). The simulation results well verify the MPPT control strategy and no-load cutting-in scheme, and also show the effectiveness of the proposed improved design method of PI controller and the coordinated control strategy.