初议修订《大型发电机变压器继电保护整定计算导则》--比率制动特性的修改

针对《大型发电机变压器继电保护整定计算导则》中的某些条款，对发电机纵差保护中大机组衰减时间常数大、非周期暂态分量电流衰减缓慢的缺点，提出采用考虑暂态性能的保护用互感器TPY型的对策；对工频短路电流倍数增大导致保护误动的缺点，分析了非周期分量系数、互感器同型系数、互感器比误差系数的整定。还探讨了变压器纵差保护中起始动作电流、起始制动电流、斜率等参数的整定。为今后大机组保护的整定计算和《导则》修订提供参考。

Suggestions to revision of guide of calculating settings of relay protection for large generator and transformer--The revision of ratio restraint characteristic

Some suggestions are made to the Guide of Calculating Settings of Relay Protection forLarge Generator and Transformer. TPY-type CT for protection considering transient performance is re-commended for the pilot differential protection of large generators to adapt for the large decaying time constant of aperiodic transient current component. The setting of non-periodic component coefficient,transformer same type coefficient and transformer ratio error coefficient is analyzed for the misoperation of protection caused by the augment of short-circuit current multiple. The pa-rameter setting of action start current,restraint start current and slope in transformer pilot dif-ferential protection is discussed as well. The suggestions provide references to the setting calcu-lations of large generator protection and the revision of the guide.