双边圆筒型永磁直线电机磁热网络耦合建模方法研究

Research on Coupled Magnetic-Thermal Network Modeling of Double-sided Permanent Magnet Tubular Machine

双边圆筒型永磁直线电机具有较高的空间利用率,在波浪能发电等场合具有良好的应用前景。但其内定子散热困难、内外定子不对称的特点使其磁热特性存在多参数、非线性和强耦合的特征。为实现其磁热特性的准确和快速求解,课题组提出一种磁热网络双向耦合迭代建模方法。首先,建立了电机磁场的自适应磁路,节点间增设半弧形漏磁磁路以精确模拟齿边漏磁,实现了等效磁网络模型的建模求解;其次,依据气体努塞尔数和热阻公式建立了集总参数热网络模型;最后,依据损耗模型的磁热相关性,利用迭代修正方法实现了磁热网络模型的双向耦合求解,改善了内定子温升。有限元及实验结果表明该方法具有快速性和准确性。

Doubled-sided permanent magnet tubular machine has higher space utilization ratio and good application prospects in fields like wave energy generation. However, characteristics like multi-parameter, nonlinear and strong coupling brings difficulties to electromagnetic analysis and thermal analysis for bad heat dissipation and asymmetry between inner and outer stators. In order to realize the accurate and fast solution of its magnetothermal characteristics, an iterative bidirectional coupled magnetic-thermal network modeling method was proposed. Firstly, adaptive connection magnetic circuit was built. Additional semi-arc leakage magnetic circuit was added to between the nodes to accurately simulate the magnetic leakage, and equivalent magnetic network model was built and solved. Secondly, a lumped parameter thermal network model was built based on Nusselt number and thermal resistance formula. Finally, the bidirectional coupling of magnetic network model and thermal network model was realized by using iterative correction method according to the magnetic-thermal correlation of the loss model, and the internal stator temperature rise was improved. The finite element and experimental results indicate the rapidity and accuracy of proposed method.