【摘要】 分析了750kV系统的分布电容和非周期分量问题,提出多种滤波器结合的滤波方法,线路保护采用较大比率制动系数和浮动制动门坎、变压器保护采用初始带制动的比率制动特性和浮动制动门槛、母线保护采用自适应加权的抗饱和措施;分析了750kV变压器励磁涌流和过励磁的问题,针对励磁涌流提出了Δ→Y变换调整变压器差动各侧的电流相位方法,针对过励磁问题提出了软件计算频率和均方根法计算电压的幅值;分析了电抗器保护匝间短路灵敏度,提出了自适应补偿零序功率方向的方法。最后总结了满足750kV工程要求的保护配置。更多还原

【Abstract】 The problems that caused by distributed capacitance and decaying non-periodic component of 750 kV system were analyzed in this paper.Several effective solutions were presented,including the new filtering method combined with some filters,adoption of high percentage restraint factor and float restraint threshold in transmission line protection,use of percentage restraint characteristic with restraint at initial period and float restraint threshold in transformer protection,application of adaptive anti-saturation principle in bus-bar protection.Inrush current and over excitation of 750 kV transformer were also analyzed,a novel method of adjusting differential current phase angle of transformer for transforming from delta to wye as well as the methods of calculating frequency by software and calculating voltage amplitude by the root-mean-square were presented.Moreover,the sensitivity of turn-to-turn fault of shunt reactor protection was analyzed and a method of adaptive compensated zero sequence direction was presented.Finally,the protection configuration that can meet the need of 750 kV project is summarized.更多还原