ANTI-ISLANDING METHOD AND DEVICE FOR DISTRIBUTED POWER SOURCE OF DIRECT-CURRENT ELECTRIC DISTRIBUTION NETWORK

摘要

An anti-islanding method and device for a distributed power source of a direct-current electric distribution network. The method comprises: inject an alternating voltage component to an output end of an AC/DC interface converter, the frequency of the alternating voltage component being less than a working frequency; sample first voltage signals of the output end of the AC/DC converter; extract a first effective value of an alternating-current signal in the first voltage signals; compare the first effective value with a first preset voltage value; and an islanding phenomenon occurs on the distributed power source when it is determined that the first effective value is less than the first preset voltage value, and control the distributed power source to stop working. By determining whether the alternating voltage component exists on the output end of the AC/DC converter, whether the distributed power source needs to stop operation is determined. If the alternating voltage component does not exist on the output end of the AC/DC converter, the distributed power source is controlled to stop operation, and whether the islanding phenomenon exists can be determined accurately in a timely manner.