距离Ⅱ段保护简化整定方法及区域式后备保护方案

A Simplified Method of Distance Relay Zone-Ⅱ Setting Calculation and a Region-based Backup Relaying Scheme

分析了传统距离Ⅱ段保护的整定难点,提出了仅按照灵敏性要求计算定值的简化整定方法。该方法不要求与相邻设备配合整定,因此降低了整定计算的复杂性,并保证了距离Ⅱ段的速动性。针对上述整定方法可能存在的失去选择性问题,提出了区域式后备保护方案,利用本站及相邻变电站传统距离保护的启动信息,构成逻辑判据,保证简化整定下的距离Ⅱ段保护的选择性。该方案不仅能正确识别故障位置,加速后备保护动作,并且具有一定的容错能力,能够应对通信故障、元件信息失效等继电保护系统的N-1问题,并由于判据仅利用有限广域的开关量信息,因此没有数据同步的问题。算例分析表明,传统距离Ⅱ段保护的简化整定方法结合区域式后备保护方案,能使原本具有矛盾、制约关系的选择性、灵敏性和速动性实现和谐统一。

The problems in the traditional method of distance relay zone-Ⅱ setting calculation are analyzed,and a novel method is proposed to simplify the setting calculation.As the simplified method is only concerned with the sensitivity requirement without asking for coordination between adjacent lines,the complexity of setting calculation is reduced while the speed of zone-Ⅱ distance relaying is ensured.However,for the possibility of loss of selectivity with the above-mentioned method under some circumstances,a region-based backup relaying scheme is proposed.The startup information of traditional distance relays in local and adjacent substations is utilized to form the logical criterion.The region-based scheme is able to correctly identify the fault location,accelerate the backup relaying,and immunize against the relaying N-1 operation status such as communication failure and element information missing.The results of a case study show that the simplified method of distance relay zone-Ⅱsetting calculation combined with the region-based backup relaying scheme has realized the unification of selectivity,sensitivity and rapidity.