基于漏磁补偿的混合电磁铁磁力修正研究

Correction of Magnetic Force of Hybrid Electromagnet Based on Magnetic Flux Leakage Compensation

电磁永磁混合磁铁的悬浮磁力具有强非线性特点,与磁铁结构密切相关,而现有混合磁铁磁力解析计算公式忽略了磁路漏磁等因素影响,在实际计算中存在较大误差.针对这一问题,建立了两种常用混合磁铁结构的磁路模型,分析了边缘磁通分布、磁路漏磁对磁铁工作磁路的影响,推导了两种混合磁铁的磁路方程及相关磁阻,提出了一种新的混合磁铁磁力修正计算方法,最终通过有限元分析对两种结构的混合磁铁磁力进行了验证.研究结果表明:由于悬浮气隙较大,电磁永磁混合磁铁在电磁力计算中漏磁影响不能忽略;采用本文磁力修正公式计算,两种混合结构电磁力误差分别降低为3.8%和8.3%.

The suspension magnetic force of electro-permanent magnets features strong nonlinearity, which is closely related to the magnet structure. The existing analytical calculation formula for magnetic force of the hybrid magnet ignores the influence of magnetic circuit leakage and some other factors, consequently resulting in big errors in actual calculations. To solve this problem, two common hybrid magnetic circuit models are established to analyze the influence of edge magnetic flux distribution and magnetic circuit leakage on the working magnetic circuit of the magnet. On this basis, the magnetic circuit equations and related reluctance of the two hybrid magnets are deduced, and a corrected calculation method of the hybrid ferromagnetic force is put forward. Finally, the corrected magnetic force of the hybrid magnets with the two structures is verified by finite element analysis. The results show that due to the large suspension air gap, the influence of magnetic flux leakage of an electro-permanent magnet cannot be ignored in the calculation of electromagnetic force. Using the magnetic force correction formula proposed in this paper, the electromagnetic force errors of magnets with the above two hybrid structures are reduced to 3.8% and 8.3%, respectively.