适用于带并抗的同杆双回线接地故障分相自适应重合闸策略

同杆双回线发生接地故障采用传统跳闸策略时可能会产生负序分量，传统自动重合闸方案在合闸前不判定故障性质，重合失败时将影响系统稳定性。针对该问题，提出了一种适用于带并抗的同杆双回线接地故障改进跳闸与分相自适应重合闸策略。首先，通过建立带并抗的同杆双回线各相之间的耦合模型并对其进行分析，提出了一种能够避免负序分量注入系统的改进跳闸策略。其次，分别对瞬时性故障和永久性故障情况下的故障相并联电抗器电流特征分析，提出了基于故障相并联电抗器微分栅电流的故障性质判据。最后，结合改进跳闸策略和故障性质判据，形成了适用于带并抗的同杆双回线接地故障分相自适应重合闸策略。PSCAD/EMTDC仿真验证了所提改进跳闸与分相自适应重合闸策略能够避免负序分量注入系统，以及在不同接地故障类型、故障位置和过渡电阻情况下都能保证输电线路重合成功率。

Phase-separation adaptive autoreclosing strategy for ground faults on double-circuit transmission lines with shunt reactors

When a ground fault occurs on double-circuit transmission lines, the conventional tripping strategy may inject negative sequence components into the system. In addition the traditional autoreclosing scheme does not determine the fault feature before reclosing, and if it is reclosed to a permanent fault, the stability of the power system will be affected. To solve the above problems, phase-separation adaptive autoreclosing suitable for grounding faults on double-circuit transmission lines with shunt reactors is proposed. First, by establishing and analyzing the phase-to-phase coupling model of double-circuit transmission lines with shunt reactors, an improved tripping strategy that can avoid the injection of negative sequence components into the power system is proposed. Secondly, faulty phase shunt reactor current characteristics are analyzed for transient and permanent fault cases, respectively, and the fault nature criterion based on differential gate current of a faulty phase shunt reactor is proposed. Finally, the improved tripping strategy and fault nature criterion are combined to form a phase-separation adaptive autoreclosing suitable for grounding faults on double-circuit transmission lines with shunt reactors. The PSCAD/EMTDC simulation verifies that the proposed improved tripping strategy and phase-separation adaptive autoreclosing can avoid the injection of negative sequence components into the system and ensure the reclosing success rate of the transmission line in different ground fault types, fault locations and transition resistances.