Operation of Automatic Transfer Switches in the Networks with Distributed Generation

Abstract

Distributed generation facilities are normally connected to distribution electrical networks or internal electrical networks of entities where automatic transfer switches (ATS) are widely used. Commissioning of generating capacities changes significantly the topology and operation, in which case the distributed generation facility can create conditions when the transfer switch does not operate, its response time increases, or a voltage avalanche occurs at the load node and ATS operation is unacceptable. The characteristic areas of post-emergency conditions are identified for the cases of emergency switching after voltage decline, which should be analyzed in the projects aimed at connecting distributed generation to existing electrical networks. The recommendations are made to improve the speed, change the operation algorithms and settings of the ATS fault detectors.