一种考虑磁滞和微观涡流效应的电磁模拟方法

An Electromagnetic Simulation Method Considering Hysteresis and Micro-Eddy Current Effect

电机和电力变压器电磁仿真以实心材料代替硅钢叠片铁心,难以准确描述涡流路径,并且忽略了涡流效应影响。该文提出了一种考虑微观涡流和磁滞的电磁模拟算法。通过一阶回转曲线计算磁滞过程的Everett函数,从而辨识逆Preisach模型的参数,并对微观涡流损耗系数进行优化拟合;构建考虑微观涡流和磁滞效应的电磁本构方程,设计有限元离散和方程组迭代的算法,实现Maxwell方程、磁滞和微观涡流场的耦合。最后,对无取向钢片35WW270进行了交变一维磁特性和旋转二维磁特性的实验。为了验证数值算法的有效性,三维磁特性测量装置简化为二维模型进行电磁有限元仿真,仿真结果与交变和旋转磁特性测量结果吻合较好,验证了叠片铁心微观涡流算法的正确性和有效性。

In the simulation of motor and power transformer, the silicon laminated core is regarded as the bulk material avoiding the huge triangulation and computation. This simplification can not describe the eddy current path and ignore the influence of the eddy current. The magnetic field equation considering the micro-eddy current and magnetic hysteresis was proposed. Firstly, the inverse Preisach hysteresis model was identified by the measurement data and the inverse Everett function was computed from first order recursive curve. And the micro-eddy current loss coefficients were optimized fitting. Secondly, the controlled electromagnetic equation was proposed to couple with the Maxwell equation, Preisach model and micro eddy current. Lastly, the alternating and rotational magnetic properties of the non-oriented silicon steel 35WW270 were measured. In order to verify the validity of the numerical algorithm, the electromagnetic finite element method（FEM） simulation was fulfilled by means of the simplified 2D model from the 3D magnetic tester. Simulation results are in agreement with the experimental results, which can prove the correctness and validity of this micro-eddy current algorithm.