基于转移潮流反应灵敏度的新型距离保护算法

Algorithm of distance protection based on transfer power flow sensibility

非故障过流引起的距离3段保护连锁跳闸是导致大停电事故的主要原因,判断与故障线路相连接的线路上产生过流的原因进而闭锁由非自身故障造成的保护动作,是避免此类大停电事故的关键。提出了一种基于转移潮流反应灵敏度的新型距离保护算法。通过比较故障时线路上的实测潮流和由故障前线路潮流及转移潮流反应灵敏度计算而来的故障潮流的近似程度,而区分转移潮流过流和真实故障过流,进而阻止由于非故障过流造成的距离3段保护误动作。在Matlab/Simulink软件环境下,对互连6母线系统在不同工况下进行了实例仿真计算,结果表明该方法具有较高的准确性和实用性。

The protective chain- trip of zone 3 induced by non- fault overcurrent is the main cause of widespread blackout ,which can be avoided by blocking out the protective action for non -self faults. An algorithm based on transfer power flow sensibility is presented for distance protection. The measured power flow is compared with that calculated from transfer power flow sensibility and the power flow before fault to distinguish the faulty overcurrent from transfer overeurrent for non- fault overeurrent blocking. Simulation of 6- bus test system is carried out under Matlab/Simulink,showing its better correctness and practicability.