Impact Analysis Method of Distributed Generations with Different Off-grid Timing on Voltage-Time Feeder Automation

With the increasing proportion of distributed generation (DG) in distribution network and the scale of distribution automation construction, the impact of DG to feeder automation system cannot be ignored, which may lead to the failure of fault isolation and recovery. Combined with the requirements of DG low voltage ride-through operation capability, this paper proposes an impact analysis method of DGs with different off-grid timings on voltage-time feeder automation. First of all, it is necessary to require the change curve of the first section switch voltage with the DG off-grid after the reclosure is reliably opened during the fault period. Then, the successful opening time of the switch should be obtained in the curve and compared with the reclosing time. If the former is larger, it indicates that DG must affect the action of switch, which can be avoided by adjusting the system time setting. Finally, the specific application of the proposed method is demonstrated in detail by using the simulation results of PSCAD / EMTDC.