Research on power quality improvement of active distribution grid based on power electronic transformer

With a growing number of DG accessing to distribution grid, there were increasingly serious of the power quality problem. The traditional approach is that installing DFACTS equipment such as filter, regulator, controller, and compensator between distribution transformer and load, which makes the distribution grid more complex. This paper focuses on the approach of applying the power electronic transformer to improve the power quality of active distribution grid. The paper proposes the main circuit topology and control strategy of the power electronic transformer. The main circuit simulation model of the power electronic transformer had also been established on Matlab/Simlink. The simulation results show that the power electronic transformer not only has the functions of the traditional distribution transformer but also can improve preferably the power quality of active distribution grid, without any other control or compensation devices.