基于相量集合的站域差动保护研究

针对智能变电站发展现状,分析了站域信息共享情况下,采样信息失步对差动保护的影响。在此基础上提出了基于相量集合的站域差动保护算法。该算法采用各支路的电流同步相量参引进行差动保护逻辑计算,依此计算出差动电流和制动电流,解决了由于采样信息失步导致的保护误动或拒动。最后,仿真结果表明,基于相量集合的差动保护算法在SV一定程度的失步情况下,差动保护的灵敏性和可靠性不受影响,能够保证站域差动保护可靠实施。因此,可以在新一代智能变电站站域保护装置上加以采用。

Research on substation differential protection based on phase set

Based on the intelligent substation development, this paper analyzes the influence of unsynchronized sampling value (SV) on differential protection under the circumstance of substation information sharing, based on which a substation differential protection algorithm based on phase set is proposed. The algorithm uses the current synchronous phasor reference citation of each branch for differential protection logic calculation, and the calculated differential current and braking current can solve protection malfunction or refuse caused by the unsynchronized SV. Finally, the simulation results show that using the differential protection algorithm based on phase set, the sensitivity and reliability are not affected under a certain extent unsynchronized SV, which ensures reliable implementation of substation differential protection. Therefore, this differential protection algorithm can be used in the new generation intelligent substation.