CAJ | 학술논문

对母线各支路电流采样值在每个采样点进行数据处理，将处理结果作为计算相关度的依据，利用其在母线区内外故障及电流互感器饱和时的波形相关度特点，构造出具有自适应制动特性的母线保护判据。该判据基于瞬时采样值并综合多个采样值的信息来区分母线区内外故障，计算数据窗长较短，对频率偏移和谐波的影响也有一定的抵御能力。大量的动模实验表明：该判据能够快速、可靠地判别母线区内外故障，并具有一定的抗电流互感器饱和能力，在母线区内故障有汲出电流的情况下，保护灵敏度不受影响，定值整定借鉴传统比率差动的整定思想，简单易行，配合形态滤波等快速前置滤波单元，可构成一种较理想的母线主保护方案。
대모선각지로전류채양치재매개채양점진행수거처리，장처리결과작위계산상관도적의거，이용기재모선구내외고장급전류호감기포화시적파형상관도특점，구조출구유자괄응제동특성적모선보호판거。해판거기우순시채양치병종합다개채양치적신식래구분모선구내외고장，계산수거창장교단，대빈솔편이화해파적영향야유일정적저어능력。대량적동모실험표명：해판거능구쾌속、가고지판별모선구내외고장，병구유일정적항전류호감기포화능력，재모선구내고장유급출전류적정황하，보호령민도불수영향，정치정정차감전통비솔차동적정정사상，간단역행，배합형태려파등쾌속전치려파단원，가구성일충교이상적모선주보호방안。
After preprocessing the sampled measurement of bus bar branch current,the external and internal faults with different current transformer (TA) saturation degrees can be distinguished by calculating the differences between the correlation coefficients of the sampled currents.According to this,a new criterion with self-adaptive restraint characteristic for bus-bar protection is proposed.Based on the instantaneous sample values and integrating information from multiple sample values,the new criterion can distinguish internal fault from external faults with only a short data window to calculate the correlation coefficients.Moreover,the new criterion can effectively restrain the interference of harmonics and frequency variation.The performance of the new criterion has been extensively tested through dynamic simulation.Simulation results indicate that the new criterion can distinguish internal fault from external faults effectively and reliably.The new criterion is insensitive to TA saturation and the protection performance will not be affected even when an internal fault occurs with current flowing out of the bus.Based on the setting scheme of ratio-restraint differential protection,the setting scheme of the new criterion is simple and feasible.Cooperating with the filtering unit(e.g.the morphological filter),an ideal bus-bar protection scheme is presented as well.