列波兰变压器功率差动保护的探究

Study of the power differential protection of Le-Blanc transformer

提出了改进列波兰变压器传统数字式保护的可行性。目前列波兰变压器仍以二次谐波制动的比率差动保护为主保护 ,励磁涌流的存在使得该保护的可靠性降低 ,而功率差动保护在励磁涌流发生一个周期后就不受其影响 ,故能够快速准确地分辨出区内故障。通过将功率差动保护与其他保护的配合使用 ,在实际系统中可以达到比较理想的结果 ,具有较大的实用价值。

This paper presents the possibility of improving the protection for Le Blanc transformer. The existing main protection algorithm for Le Blanc transformer is the traditional biased differential protection combined with 2nd hamonic restraints,and the existence of magnetizing inrush current reduces the reliability of digit protection. Power differential protection will not be affected by magnetizing inrush current after a cycle of such current occurrence, so it can discern internal faults and other phenomenon. Working with other protection methods, power differential protection is proved to be ideal by experiments,shoving a great useful value.