Smart vector-decoupling control of three phase rectifiers for grid connectivity of sustainable energy sources

In this paper, some of the aspects related to the connectivity of DC microgrids to the main grid are investigated. The system under study is dependent mainly on sustainable energy sources. A fully controlled rectifier has been designed to tie the DC grid with the AC one. A vector decoupling controlled sinusoidal pulse width modulation (SPWM) technique has been used to allow the designed rectifier to maintain a constant output voltage while being able to control the active and reactive power drawn from the grid independently. Hence, this controlled rectifier acts as a voltage regulator for the DC microgrid and has a uni-directional power flow capability from the AC grid to the DC microgrid. Moreover, in order to maximize the operating range of the controlled rectifier. An adaptive controller has been used. The proposed controller is a PI controller that has been tuned at different operating ranges. Then, a fuzzy controller is used to select the most suitable PI parameters based on the loading condition. Both simulation and experimental results verify the validity of the proposed system.