High-bandwidth controller design for dual-stage actuator system in hard disk drives
High-bandwidth controller design for dual-stage actuator system in hard disk drives
复制标题
DOI：
10.1177/10775463211062337
复制
发表时间：
2022-01
影响因子：
2.8
通讯作者：
S. Yabui;T. Atsumi
中科院分区：
文献类型：
--
作者：
S. Yabui;T. Atsumi
大容量硬盘驱动器对于信息社会的发展至关重要。在磁盘定位控制系统中，硬盘驱动器的容量取决于读写数字数据的磁头的定位精度。因此，发展大容量硬盘驱动器必须提高定位精度。硬盘驱动器采用双级致动器系统来精确控制磁头。一种双级执行器系统，由音圈电机和微执行器组成。在微执行器中，需要在头部定位精度和行程限制之间进行权衡。特别是，在传统的控制器设计中，微执行器需要驱动以补偿低频振动。为了克服这一折衷，本研究提出了一种用于双级执行器系统中的微执行器的高带宽控制器设计。该方法通过提高音圈电机低频反馈控制器的增益，减小了微执行器的行程要求。虽然音圈马达控制回路变得不稳定，但微执行器在高频下稳定整个反馈回路。结果，与传统控制方法相比，该控制系统提高了定位精度，并减少了所需的微执行器行程。
Large-capacity hard disk drives are important for the development of an information society. The capacities of hard disk drives depend on the positioning accuracy of magnetic heads, which read and write digital data, in disk-positioning control systems. Therefore, it is necessary to improve positioning accuracy to develop hard disk drives with large capacities. Hard disk drives employ dual-stage actuator systems to accurately control the magnetic heads. A dual-stage actuator system consists of a voice coil motor and micro-actuator. In micro-actuators, there is a trade-off between head-positioning accuracy and stroke limitation. In particular, in a conventional controller design, the micro-actuator is required to actuate such that it compensates for low-frequency vibration. To overcome this trade-off, this study proposes a high-bandwidth controller design for the micro-actuator in a dual-stage actuator system. The proposed method can reduce the required stroke of the micro-actuator by increasing the gain of the feedback controller of the voice coil motor at low frequencies. Although the voice coil motor control loop becomes unstable, the micro-actuator stabilizes the entire feedback loop at high frequencies. As a result, the control system improves the positioning accuracy compared to that achieved by conventional control methods, and the required micro-actuator stroke is reduced.