基于磁悬浮式惯性稳定平台的冷原子重力仪主动隔振技术研究

Cold atom gravimeter is a new absolute gravimeter, which has the advantages of high accuracy, good repeatability, strong stability and miniaturization. In order to realize high precision gravity measurement with cold atom gravimeter in complex external environment, active vibration isolation technology is necessary to isolate the interference caused by environmental vibration. In order to solve this problem, a new active vibration isolation technology for cold atom gravimeter based on maglev inertial stabilized platform is proposed in this paper. It is a combination of the magnetic suspension technology with the traditional inertial stabilized platform, which uses magnetic bearings instead of traditional bearings. It compensates low frequency vibration with high accuracy in real time, so as to maintain the attitude stability of the maglev inertial stabilized platform relative to the ground. The main contents include three parts, the first part is the system design and dynamic model establishment of the maglev inertial stabilized platform, the second part is the research on the control strategy of the active vibration isolation method based on the maglev inertial stabilized platform, and the last part is the experimental study of the active vibration isolation method based on the maglev inertial stabilized platform. The maglev inertial stabilized platform can eliminate the adverse effects of shaft friction compared with the traditional inertial stabilized platform. As a result, the stability accuracy and vibration isolation performance of the maglev inertial stabilized platform will be greatly improved, which is extremely important for cold atom gravimeter to realize high-precision gravity measurement in complex external environment，and hence has great value and significance.

冷原子重力仪是一种新型绝对重力仪，具有测量精度高、可重复性好、稳定性强、可以小型化等优点。若要实现其在复杂外部环境下的高精度重力测量，必须采用主动隔振技术隔离环境振动带来的干扰。针对这一问题本课题提出一种基于磁悬浮式惯性稳定平台的主动隔振新技术。该技术将磁悬浮技术与传统惯性稳定平台技术结合，采用磁悬浮轴承代替传统轴承，实现平台对低频振动的高精度实时补偿，使平台姿态相对大地始终保持惯性稳定。本课题的研究内容主要包括：1)磁悬浮式惯性稳定平台系统方案的设计和动力学模型的建立；2)基于磁悬浮式惯性稳定平台的主动隔振控制算法研究；3)基于磁悬浮式惯性稳定平台的主动隔振方法实验研究。相比传统惯性稳定平台，磁悬浮式惯性稳定平台能够消除轴系摩擦力的不利影响，其稳定精度和隔振性能都将得到大幅提升，从而实现冷原子重力仪在复杂外部环境下的高精度重力测量，具有重要研究价值和意义。

冷原子重力仪若要实现其在复杂外部环境下的高精度重力测量，必须依靠基于惯性稳定平台的主动隔振技术来隔离环境振动带来的干扰，因此惯性稳定平台是冷原子重力仪动态测量的关键技术。为了进一步提升惯性稳定平台的精度，本课题提出一种基于磁悬浮式惯性稳定平台的主动隔振新技术。该技术将磁悬浮技术与传统惯性稳定平台技术结合，采用磁悬浮轴承代替传统轴承，实现平台对低频振动的高精度实时补偿，使平台姿态相对大地始终保持惯性稳定。该技术既能对低频、大振幅的振动进行实时补偿，又能消除摩擦力的不利影响提高系统稳定精度。项目主要研究内容包括：1)对磁悬浮轴承控制机理进行研究并建立了磁悬浮轴承控制系统的数学模型；2)完成了磁悬浮式惯性稳定平台控制系统的理论研究；3)完成了磁悬浮式惯性稳定平台整体方案的设计和论证；4)完成了磁悬浮式惯性稳定平台原理样机的研制；5)完成了磁悬浮式惯性稳定平台控制器、磁悬浮轴承驱动器的研制。总之，本课题的研究对于提升基于磁悬浮式惯性稳定平台的主动隔振系统的稳定精度具有重要意义。