一种铁磁物体固定磁性反演新方法

A New Retrieval Method for Permanent Magnetism of Ferromagnetic Objects

摘要:

对铁磁物体固定磁性计算问题进行了研究,提出了一种基于磁场积分法和 TTLS 正则化方法的铁磁物体固定磁性计算的新技术,为铁磁物体固定磁性计算难题的求解提供了一条新的技术途径。 该技术以三维磁场积分法为数值计算方法。 首先由正演模型计算得到了铁磁物体感应磁场分布,其次基于铁磁物体外部空间磁场测量数据和感应磁场计算值,建立了固定磁性反演模型,并利用截断总体最小二乘正则化方法处理反演模型的病态性,以减小测量误差对反演计算结果的影响。 由正反演模型相结合即可实现铁磁物体固定磁性的计算。 钢板固定磁性计算实例表明,该方法具有较好的计算精度,能够有效重建铁磁物体内部固定磁性分布。

Abstract:

The problem of permanent magnetism calculation of ferromagnetic objects is studied, a new technique based on the magnetic field integral method and truncated total least square (TTLS) method is proposed to solve the problem, which provides a new technical approach for permanent magnetism calculation of ferromagnetic objects. Three-dimensional magnetic field integral method is adopted in the provided method. Firstly, the forward model is used to calculate the induced magnetic field distribution of ferromagnetic objects. Secondly, based on magnetic field’s measured data of external space of ferromagnetic objects and calculated value of induced magnetic field, the retrieval model of permanent magnetism is established. In order to reduce the effects of meas- urement errors on retrieval calculation results, this paper uses TTLS method to solve pathological retrieval model. Permanent mag- netism calculation of ferromagnetic objects is realized through combing the forward model with retrieval model. The instance of steel plate’s permanent magnetism calculation shows that the proposed method has good calculation accuracy, and it can reconstruct the internal permanent magnetism distribution of ferromagnetic objects efficiently.