Stator voltage sensorless DFIG with low voltage ride-through capability using series and parallel grid side converters

Due to the drastic increase of the wind turbines installed capacity, the grid integration codes address many restrictions over their performance during both normal and abnormal conditions. The main aim of such codes is to operate the wind turbines like other conventional power sources. In this paper a series grid side converter is added to the conventional DFIG wind turbine configuration to add low voltage ride through capability. This target is achieved without the need to neither measure nor estimate the stator voltage or flux, hence simplifying the control scheme. The system model and the control scheme for 1.5 MW DFIG wind turbine are constructed and simulated using MATLAB/SIMULINK environment. The simulation results are intensively proving the effectiveness of the proposed scheme.