Research on Power Quality Control Method of Active Distribution Network with Microgrids

摘要

The microgrid is a weaker inertial system than the traditional large grid, which contains many power electronic converters and is a highly nonlinear environment. In view of the above problems, this paper adopts an improved power control method, so that the micro-source output voltage has no static difference and reactive output. Independent of the line connection impedance. For the low-voltage micro-grid, the problem of low power distribution accuracy and nonlinear load between the traditional micro-sources of the droop controller is adopted. By designing the virtual impedance, the equivalent line impedance is designed to be resistive near the power frequency. The line impedance characteristics of the low-voltage micro-grid reduce the sensitivity of the power-average control of the micro-source inverter to the impedance of the output line, and ensure a smooth transition of the grid-connected process.