采用分相重合方式的风电送出线路自适应重合闸策略

Adaptive Reclosing Scheme for Wind Power Outgoing Line Using Partial-phase Reclosing

风电机组对负序电流耐受能力不强,当风电场(群)能量馈出通道不止一条时,风电送出线路多采用三相一次重合闸。若风电送出线路未配置并联电抗器,线路三相跳闸后,缺乏耦合回路,为自适应重合闸故障性质判定带来了困难。针对上述问题,提出一种能够适用于风电送出线路的新型自适应重合闸策略。该策略采用单侧分相重合的方式,以应对多种风电送出线路故障,并构造了相间电容耦合回路;该策略基于电容耦合特性,采用电压幅值判据,实现对故障性质及故障熄弧时间的快速、准确判定。理论推导和基于PSCAD/EMTDC平台仿真实验证明,所提自适应重合闸策略能够避免对风电机组注入负序电流,同时显著提升风电送出线路重合闸成功率,保证风电场(群)电能外送的连续性。

Wind turbines are vulnerable to the negative sequence current injection.Therefore,a three-phase reclosing scheme is generally utilized in the outgoing lines when there is more than one outgoing line for the wind farm(s).When the shunt reactors are not installed,it is difficult to identify the transient fault from the permanent one because of the absence of the coupling loop after a three-phase trip of the outgoing line.To solve the abovementioned problems,a novel adaptive reclosing scheme for wind power outgoing line is proposed in this study.Specifically,a single-terminal partial tripping method is proposed for multiple types of outgoing line faults;simultaneously,phase-to-phase coupling loops are established by the tripping.Based on the capacitor coupling characteristics,the transient fault is rapidly and accurately identified from the permanent one by the voltage magnitude criterion.The theoretical derivation and simulation experiments based on the PSCAD/EMTDC platform demonstrate that the proposed adaptive reclosing scheme can avoid the injection of negative sequence currents into wind turbines,while significantly improving the reclosing success rate of wind power outgoing lines and ensuring the power transmission continuity of the wind farm(s).