含电力变压器和相角调节器的互联系统中内部故障与其他暂态的判别
Discrimination of Internal Faults and Other Transients in an Interconnected System with Power Transformers and Phase Angle Regulators
AI总结：
本文提出基于梯度提升分类器和信息增益特征的方案，在含变压器与相角调节器的互联系统中以高平衡准确率区分内部故障与六类暂态扰动，并定位故障单元、识别故障类型，为差动继电器提供 supervisory control。
摘要：
本研究解决了在含相角调节器（PAR）和电力变压器的5母线互联系统中，内部故障的准确检测与暂态分类问题。该分析可防止差动继电器在非故障暂态情况下发生误动作，这些暂态包括励磁涌流、 sympathetic inrush（ sympathetic inrush）、带CT饱和的外部故障、电容器投切、非线性负载投切以及铁磁谐振。采用梯度提升分类器（GBC），基于由变化检测器记录的1.5个周波的三相差动电流，将内部故障与暂态扰动区分开来。检测到内部故障后，使用GBC定位故障单元（电力变压器、PAR串联单元或励磁单元）并识别故障类型。若检测到暂态扰动，则由另一个GBC将其分类为六种暂态扰动。使用基于信息增益获得的五个最相关的频域和时域特征来训练和测试分类器。所提算法以99.95%的平衡准确率区分内部故障与其他暂态。故障变压器单元的定位平衡准确率为99.5%，不同暂态扰动的识别平衡准确率为99.3%。此外，针对所涉及变压器的不同额定值和连接方式、CT饱和以及信号中的噪声水平，验证了该方案的可靠性。这些GBC分类器可与传统差动继电器协同工作，并对其运行提供 supervisory control（ supervisory control）。使用PSCAD/EMTDC软件对暂态进行仿真，并建立双绕组和三绕组变压器模型以产生内部故障，包括匝间故障和绕组间故障。
英文摘要：
This study solves the problem of accurate detection of internal faults and classification of transients in a 5-bus interconnected system for Phase Angle Regulators (PAR) and Power Transformers. The analysis prevents mal-operation of differential relays in case of transients other than faults which include magnetizing inrush, sympathetic inrush, external faults with CT saturation, capacitor switching, non-linear load switching, and ferroresonance. A gradient boosting classifier (GBC) is used to distinguish the internal faults from the transient disturbances based on 1.5 cycles of 3-phase differential currents registered by a change detector. After the detection of an internal fault, GBCs are used to locate the faulty unit (Power Transformer, PAR series, or exciting unit) and identify the type of fault. In case a transient disturbance is detected, another GBC classifies them into the six transient disturbances. Five most relevant frequency and time domain features obtained using Information Gain are used to train and test the classifiers. The proposed algorithm distinguishes the internal faults from the other transients with a balanced accuracy of 99.95%. The faulty transformer unit is located with a balanced accuracy of 99.5% and the different transient disturbances are identified with a balanced accuracy of 99.3%. Moreover, the reliability of the scheme is verified for different rating and connection of the transformers involved, CT saturation, and noise levels in the signals. These GBC classifiers can work together with a conventional differential relay and offer a supervisory control over its operation. PSCAD/EMTDC software is used for simulation of the transients and to develop the two and three-winding transformer models for creating the internal faults including inter-turn and inter-winding faults.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
