基于二次谐波的自适应制动涌流方案

Adapative secondary harmonic restraint method for inrush current

讨论了几种二次谐波变压器差动保护的原理,分析了各自的可靠性和灵敏性,结果表明:虽然采用二次谐波制动原理,但是不同制动涌流的方式,制动效果存在较大的差别。二次谐波制动原理在特高压大型变压器保护中的应用还有待进一步改进和完善。在总结二次谐波制动的特点后,提出了改进的制动方式,同时针对励磁和故障时直流衰减的不同提出了自适应二次谐波的制动方式。应用该方法差动保护明显优于采用传统二次谐波制动判据的保护,具有较好的工程应用价值。

This paper analyzes the differential protection principles for secondary harmonic transformer and discusses their reliability and sensitivity. The results show that different restraint inrush methods have different restraint effects. In the EHV transformer protection system, the restraint method should be improved. This paper puts forward a new restraint method based on the characteristic of secondary harmonic method. Meanwhile, based on the difference of DC decaying when excitation and fault, an adaptive secondary harmonic restraint method is proposed. The transformer differential protection applying the proposed method is evidently superior to traditional transformer differential protection based on secondary harmonic restraint criteria, so the proposed method is available for engineering application.