适应于风电接入系统的抗高阻接地时域方程距离保护研究

双馈风电接入系统带来的高次谐波、频率偏移等故障特性使传统工频量距离保护适应性存在问题。基于时域距离保护原理较适用于风电系统送出线，但在送出线发生单相经高阻接地故障时，易发生距离I段区内拒动现象，保护适应性存在问题。提出了一种抗高阻接地时域方程距离保护原理。基于时域距离保护原理，通过对时域方程进行重构，增加过渡电阻待识别量，从原理上解决了时域距离保护未充分考虑过渡电阻所带来的不利影响的问题。仿真结果表明，该原理能较好地适用于风电系统送出线，并且有效地避免了风电系统送出线距离I段区内发生单相经高阻接地故障时距离保护拒动的现象。

Research on high resistance grounding time domain equation based distance protection for wind power accessed power system

The feasibility of protection adopts traditional model identification method based on time-domain signal on DFIG based wind power outgoing lines is low because of the high harmonic and frequency deviation. Although the distance protection based on time-domain performs well when being applied on wind power outgoing lines, miss operations of distance zone I may occur under outgoing line single phase high resistance grounding faults. Aiming at the feasibility problem mentioned above, a principle of high resistance grounding time domain equation based distance protection is proposed. Based on time domain distance protection principle, by reconstructing the time domain equation and adding the identification of transition resistance, the defects caused by somewhat ignoring transient resistance is overcome. Simulation results show that, the proposed high resistance grounding time domain equation based distance protection can adapt to the outgoing line of wind farm accessed power system, and avoid the miss operations of distance zone I under outgoing line single phase high resistance grounding faults effectively. This work is supported by National Natural Science Foundation of China (No. 51467019).