基于CT饱和综合判据的变压器差动保护的研究

Study of transformer differential protection based on the CT-saturation-integrate-method

介绍了一种新型的基于CT饱和综合判据的变压器比率制动差动保护方案。首先,分析了比率制动差动保护的原理及算法;其次,在分析了谐波制动法、时差法和附加稳定区法的基础上,得出了新型的CT饱和综合判据并分析了其优点;再次,给出了基于CT饱和综合判据的变压器差动保护的数值计算方法,可有效减轻CPU的负担,从而使程序运行更稳定;最后利用动模试验验证了基于CT饱和综合判据的比率制动差动保护的可靠性与快速性,并且验证了它在CT饱和延时闭锁差动保护期间可以快速反应变压器区内故障。

A new transformer differential protection is introduced. First, this paper analyzes scheme and arithmetic of transformer differential protection. Secondly, it puts forward the CT-Saturation-Integrate-Method and its merits based on harmonic restraint method, time difference method and additional restraint region method. Thirdly, it puts forward the numerical computation method of transformer differential protection. Finally, it tests the higher reliability and rapidness of the CT-Saturation-Integrate-Method dependent of experimentation of the dynamic model. Also, the method can identify the transformer＇s conversion fault rapidly while differential protection is blocked.