双馈集群汇集站主变及送出线路继电保护研究

Research of transformer and outgoing line protection of collection station where cluster of double-fed wind farms put in

传统风电场主变、送出线路保护配置多从系统角度考虑,存在保护动作的选择性、灵敏性问题。尤其是风电集群汇集站主变、送出线路保护适应性问题亟待于进一步研究。为此,结合新疆实际电网结构,考虑双馈风电场故障电流、电压特征,理论分析故障电流频率偏移对差动保护的影响。仿真分析双馈集群风电场接入对汇集站主变相量值差动、采样值差动保护及送出线路不同类型保护的影响。依此提出双馈集群汇集站主变、送出线路保护的相应完善措施,为解决当前电网面临的实际问题提供参考。

Traditional primary transformer protection and outgoing line protection of wind farm taken more consideration of system perspective, the selectivity and sensitivity of protection operation maybe not reliable. Then, the adaptability of transformer and outgoing line protection needs to be studied further, especially for the collection station which is a cluster of wind power connected to grid. For this reason, based on Xinjiang actual grid structure, and considering characteristics of fault current and voltage of double-fed wind farm, this paper analyzes theoretically the impact of fault current frequency offset for differential protection, simulates the impact of phase differential and sampled value differential protection for transformer and types of protection for outgoing line, under the cluster of double-fed wind farm connected to grid. Finally, it proposes the measures for collection station transformer and its outgoing line protection, which provides a reference for solving practical problems faced by the current grid.