一种新的差动保护动作行为分析方法:分析篇

运用在穿越电流倍数一电流互感器传变率(流出电流比)坐标平面上分析差动保护性能的方法，详细分析了两种新型标积制动判据中各个参数变化时，对判据的抗电流互感器饱和性能和反应内部故障灵敏性的影响。通过这个新的坐标平面，可以有针对性地调节比例制动特性的各个参数，将判据在电流互感器饱和时最易误动的动作点配置电流互感器误差最小的区域。同时尽可能将拒动区配置在系统不可能或很少可能运行的区域，从而最大限度地发挥判据的效能。通过对比分析，明晰了两种判据的优缺点，两种判据在电流互感器饱和时具有同样的安全性，但采用条件动作区的判据在反应轻微内部故障时具有更好的灵敏性和灵活性，略优于采用制动区的判据。

A NOVEL ANALYSIS METHODOLOGY OF DIFFERENTIAL PROTECTION OPERATION BEHAVIOR: Part Two Analysis

Based on the new methodology to analyze the operating behavior of the differential protection, which is proposed in the Part One, both the abilities immune to the current transformer saturation and the sensitivities of these two novel product restraint criteria are investigated with respect to the change of the settings in the percentage differential characteristic plane. It is proved that each parameter of the percentage differential characteristics can be adjusted as required. In this way, the operating point which is most possibly subject to the mal-operation can be configured to the one at which the current transformer has the least transferring error. Meanwhile, the fail-to-trip area should be arranged to the operation conditions which impossibly or rarely occur. With this arrangement, the advantages of the criteria can be highlighted and the disadvantages can be avoided. On the basis of comparative analysis, these two criteria have identical security in the condition of the current transformer saturation. However, the one with conditional operation area has higher sensitivity and flexibility in the occasion of light internal faults, which is hence slightly better than that using restraint area.