基于棱边有限元的变压器场路耦合瞬态模型  

Transient Magnetic-Circuit Coupled Model of Transformer Based on Edge Finite Element Method

作　　者：王泽忠[1] 潘超[1] 周盛[2] 刘连光[1] 

机构地区：[1]华北电力大学电气工程学院,北京102206 [2]华北电力大学高电压与电磁兼容北京市重点实验室,北京102206

出　　处：《电工技术学报》2012年第9期146-152,共7页Transactions of China Electrotechnical Society

基　　金：国家国际科技合作项目(2010DFA64680);北京市优秀博士学位论文指导教师科技项目(YB20101007901)

摘　　要：提出了一种新的基于棱边有限元法的变压器场路耦合瞬态模型。为讨论节点有限元法与棱边有限元法的计算区别,根据实际变压器参数建立模型,利用Ansys二维轴对称单元、三维节点单元和棱边单元,研究铁心磁场分布和磁通连续性,并得出结论,节点有限元法在变压器电磁场计算中存在较大的误差,棱边有限元法可以显著提高计算精度。基于棱边有限元法建立场路耦合瞬态模型,在电路模型中利用动态电感参数,建立瞬态电路偏微分方程数学模型,用四阶龙格库塔法求解;根据能量扰动原理,在磁场计算中根据能量增量计算动态电感;代入瞬态电路方程,实现场路耦合。分析线圈电流、电感参数和铁心漏磁情况,并说明瞬态耦合模型的有效性与合理性。A transient magnetic-circuit coupled computation based on finite element method（FEM） is proposed in this paper. In order to discuss the computational effects of the node FEM and edge FEM, axisymmetric plane element, and the two elements above in Ansys are used. Magnetic and flux continuity in iron-core of different models about transformers are analyzed. The research shows that flux leakage and computing errors may be caused by the node FEM in the 3D electromagnetic model of transformer, which can be settled by edge FEM. On this basis, transient magnetic-circuit coupled model is built. The dynamic inductance is used in the partial differential equation of transient circuit. And the nonlinear magnetic is solved with edge FEM. According to energy perturbation of magnetic, the dynamic inductance is calculated and substituted into the transient equation of circuit. This coupled method can be realized by the fourth Runge-Kutta. Computation and comparison of currents, inductance and leak are carried out. As a result, the computing problem of node FEM is proved, and the transient coupled method is verified with feasibility and validity.

关 键 词：棱边有限元法 瞬态场路耦合 变压器 动态电感 

分 类 号：TM153[电气工程—电工理论与新技术]