A Setting Method of the Second-zone Grounding Distance Protection for 110 kV Lines Applicable to Distributed Wind Power Integration

Abstract

On the 110 kV lines connected to the distributed wind power， following the conventional protection configuration requirements， the distributed wind power side is usually not equipped with protection. However， since the distributed wind power is connected， the current and direction of power flow of the system have changed， resulting in isolation failure of fault in case of faults. So far there is no research to analyze the setting method for grounding distance protection on the distributed wind power side. Considering the fault characteristics of distributed wind power， the paper calculates the minimum composite branch coefficient under various operation modes of the system through sequence network analysis and proposes a setting method for the second-zone grounding distance protection on wind power side based on the minimum composite branch coefficient. A model is established on PSCAD/EMTDC for simulation and validation， and the simulation results show that the improved setting method is feasible.

Keywords

• distributed wind power
• distance protection
• branching coefficient
• value setting