基于全绕组拓扑结构的移相变压器建模及应用

Modeling and application of phase-shifting transformer based on full winding topology structure

针对现有移相变压器稳态数学模型不能适用于内外部端口故障电气量计算的问题,基于相分量法建立其全相数学模型。以对称双芯式移相变压器为例,根据其电磁约束关系,推导出节点电压与电流间的关系式,再通过绕组拓扑结构对节点进行合并及接地处理,得到移相变压器的导纳矩阵和全相等效电路模型,并对矩阵进行修正以适应不同故障情况下的计算。最后,利用该模型分析了对称双芯式移相变压器在不同相序网络中的运行特性。对比仿真结果可知,所建全相数学模型能够准确计算各类端口故障下的电气量,所得等效相序电路可以有效反映不同序分量下移相变压器的运行特性。

For the problem that the existing steady-state mathematical model of phase-shifting transformer cannot be applied to the calculation of electrical quantities of internal and external port faults,its fullphase mathematical model is established based on the phase-component method.Taking symmetrical twocore phase-shifting transformer as an example,the relationship equation between node voltage and current is derived according to its electromagnetic constraint relationship,and then the nodes are combined and grounded by winding topology structure to obtain the admittance matrix of the phase-shifting transformer and the full-phase equivalent circuit model,then the matrix is modified aiming at adapting to the calculation under different fault conditions.Finally,the operating characteristics of symmetrical two-core phase-shifting transformer in different phase sequence networks are analyzed by the proposed model.Comparing the simulative results,it can be seen that the proposed full-phase mathematical model can accurately calculate the electrical quantities of various port faults,and the equivalent phase sequence circuit can effectively reflect the operating characteristics of phase-shifting transformers under different sequence components.