Microgrid reactive power compensation and harmonic suppression control method based on master-slave SVG

Abstract

In order to solve the problems of power factor decline and power quality degradation caused by a large number of nonlinear loads in microgrids, this paper proposes a master-slave SVG and its control method. The master SVG usually has a large capacity and a low switching frequency. It adopts the indirect current control method to mainly compensate the reactive power of the grid. Due to the characteristics of the SVG converter itself, a certain degree of harmonics will also be generated during operation. This part of the harmonics and the harmonics of the grid itself are compensated by the slave SVG. In the harmonic extraction method, the harmonic extraction method based on instantaneous power theory is adopted. Because the harmonic content in the power grid is small, the capacity of the slave SVG is much smaller than that of the master SVG, so that each part can be fully utilized and has a strong economic efficiency. Finally, the effectiveness of the method proposed in this paper is verified by simulation.