摘要
为了分析Sen变压器(Sen transformer,ST)在双芯结构下的电磁特性,该文提出一种基于统一磁路模型(unified magnetic equivalent circuit,UMEC)法的双芯Sen变压器(two-core Sen transformer,TCST)电磁暂态模型。首先,根据TCST内部绕组的磁耦合关系,将TCST分为串联变和励磁变两部分,并基于各自的铁芯结构建立了它们的磁等值回路;其次,采用UMEC原理分别对上述两部分进行电磁暂态建模,并由TCST内部串–励部分之间的电气连接关系,将该串–励部分结合,继而构建了TCST的电磁暂态模型。最后,借助MATLAB和PSCAD/EMTDC进行了解析计算与时域仿真分析,验证了该文所提模型的有效性。通过与现有论文电流电压和功率结果的对比,发现流过TCST分接开关的电流约为线路电流的50%,可有效降低分接开关的制造成本。同时TCST的实际调节步长相比于单芯结构的ST(single-core Sen transformer,SCST)要小,约为SCST的0.5倍,使得其控制精度更高。
This paper proposes an electromagnetic transient model of the two-core Sen transformer(TCST)based on the unified magnetic equivalent circuit(UMEC)in order to analyze its electromagnetic characteristics.Firstly,the TCST may be divided into the two parts of the series winding and the exciting winding so that their magnetic equivalent circuits are established based on their iron core structures respectively,according to the magnetic coupling relationships among the internal windings of the TCST.Secondly,with the mathematical expressions of the electromagnetic transient models derived by the UMEC method for the two parts separately,an electromagnetic transient model of the TCST can be acquired by the combination of the series winding and the exciting winding in the light of their electrical connections in the TCST.Finally,with the help of the MATLAB and the PSCAD/EMTDC,the analytical calculation and the time-domain simulation have been carried out,proving the effectiveness of the proposed model.In comparisons with the results involving the currents,the voltages and the power flows in the existing published papers,it is found that the current flowing through the tap-changers in the TCST is about 50%of the line current,which can effectively reduce the manufacturing cost of the tap-changer.Meanwhile,the actual adjustment step length of the TCST is about 0.5 times smaller than that of the single-core Sen transformer(SCST),which may lead to more accurate performance in the TCST.
作者
卜亮
韩松
周超
冯金铃
BU Liang;HAN Song;ZHOU Chao;FENG Jinling(School of Electrical Engineering,Guizhou University,Guiyang 550025,Guizhou Province,China)
出处
《电网技术》
EI
CSCD
北大核心
2021年第8期3283-3290,共8页
Power System Technology
基金
贵州省普通高等学校科技拔尖人才支持计划(2018036)
贵州省科学技术基金(黔科合基础20191100,2021277)。
关键词
Sen变压器
双芯结构
统一磁路模型
电磁暂态模型
串联电压补偿
Sen transformer
two-core structure
unified magnetic equivalent circuit
electromagnetic transient model
series compensating voltage
