DC-voltage regulation of a five levels neutral point clamped cascaded converter for wind energy conversion system

Multilevel converters are widely recognized as a suitable solution for directly interfacing different types of power sources and energy storage systems to the medium voltage grids, due to their ability in high-voltage and high-power applications. The DC-voltage regulation of a five-level neutral-point clamped (NPC) in closed loop is presented. It consists to regulate the average value of the DC-voltage by using one loop instead of four loops. The modeling and the control of the different components of the wind energy conversion system are presented. The wind turbine is controlled using the maximum power point tracking algorithm (MPPT) based on the wind speed estimation. The vector control of active and reactive power is used to control the doubly fed induction generator (DFIG) through the rotor. The dynamic behavior of the global system is simulated in MATLAB/Simulink interface programming. The results are shown to validate the effectiveness of the proposed system.