Anti-islanding method for distributed generator in direct current distribution grid and anti-islanding device therefor

摘要

Provided are an anti-islanding method for a distributed generator in a direct current distribution grid and an anti-islanding device therefor. The method includes: feeding an alternating voltage component into an output end of the AC/DC interface transverter, a frequency of the alternating voltage component being less than the power frequency; sampling a first voltage signal of an output end of the DC/DC transverter; extracting a first effective value of an alternating signal included in the first voltage signal; comparing the first effective value with a first preset voltage; and controlling the distributed generator to stop operation, in a case that it is determined that the first effective value is less than the first preset voltage, which indicates that islanding occurs for the distributed generator.