可调磁体：动态和精密应用的建模和验证
Tunable Magnets: modeling and validation for dynamic and precision applications
摘要：
致动器自加热限制了可实现的力，并且可能导致不必要的结构变形。这在准静态致动系统中尤其明显，该系统要求致动器在延长的时间段内保持稳定的位置。作为解决方案，我们使用可调磁铁的概念。可调磁铁依靠原位磁化状态调整的铝镍钴合金，以创造一个无限可调的磁通量。它们由AlNiCo低矫顽力永磁体和磁化线圈组成。在调谐之后，AlNiCo保持其磁场而无需进一步的能量输入，这消除了静态热耗散。为了能够在致动系统中实现，AlNiCo需要在存在变化的系统气隙的情况下是鲁棒可调的。我们实现这一点，通过实施磁化状态调谐方法，基于磁路模型的致动器，测量AlNiCo BH数据和气隙磁通反馈控制。所提出的调谐方法包括2个主要步骤。预测步骤，在此期间确定所需的磁体操作点，以及退磁步骤，其中反馈控制器驱动退磁电流以接近该操作点。利用该方法对磁阻致动器结构中的AlNiCo 5可调谐磁体进行了调谐，在200 μm的气隙范围内，最大误差为15.86 mT，最小精度为0.67 mT。有了这样的调谐精度，在静态期间致动器加热几乎被消除。只需要很小的偏置电流来补偿调谐误差。
英文摘要：
Actuator self-heating limits the achievable force and can cause unwanted structural deformations. This is especially apparent in quasi-static actuation systems that require the actuator to maintain a stable position over an extended period. As a solution, we use the concept of a Tunable Magnet. Tunable magnets rely on in-situ magnetization state tuning of AlNico to create an infinitely adjustable magnetic flux. They consist of an AlNiCo low coercivity permanent magnet together with a magnetizing coil. After tuning, the AlNiCo retains its magnetic field without further energy input, which eliminates the static heat dissipation. To enable implementation in actuation systems, the AlNiCo needs to be robustly tunable in the presence of a varying system air-gap. We achieve this by implementing a magnetization state tuning method, based on a magnetic circuit model of the actuator, measured AlNiCo BH data and air-gap flux feedback control. The proposed tuning method consists of 2 main steps. The prediction step, during which the required magnet operating point is determined, and the demagnetization step, where a feedback controller drives a demagnetization current to approach this operating point. With this method implemented for an AlNiCo 5 tunable magnet in a reluctance actuator configuration, we achieve tuning with a maximum error of 15.86 "mT" and a minimum precision of 0.67 "mT" over an air-gap range of 200 "μm". With this tuning accuracy, actuator heating during static periods is almost eliminated. Only a small bias current is needed to compensate for the tuning error.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
