Stator Synchronization and Dynamic Operations of CBF-FLL Filter Controlled Wind Driven DFIG-Battery Based Microgrid for Rural Electrification

In this paper, an unique wind turbine driven doubly fed induction generator (DFIG)-battery energy storage (BES) based microgrid topology is proposed, which is suitable for rural electrification. In this system, a local grid is formed by BES and the stator of the machine is connected to it, when the wind turbine (WT) operates in peak power point (PPP) zone. Step by step procedures for stator synchronization are given. Complex band pass filter - frequency locked loop (CBF-FLL) based control algorithm is utilised for load side converter (LSC) to get enhanced dynamic response of the system in all winds and loading conditions. The simulation of the system is done in different operating conditions, such as: synchronization, transient conditions like: changing wind speeds, and changing load condition using Simulink/MATLAB. The THD of stator currents and the grid voltages are obtained within the limit of the IEEE 519 standard. Moreover the stator operates at unity power factor (UPF). So, power quality improvement is achieved.