超高速超精密空气静压电主轴系统热行为及主动热控制研究

Ultra-high speed and ultra-precision aerostatic motorized spindles are one of the kernel functional components for high precision, high efficiency and high speed cutting of the ultra-precision micro-cutting CNC machine tools. The spindle systems are characterized by using aerostatic bearings and electromagnetically actuated direct drive, and the thermal stability is thus greatly affected by multiphysics coupling from multiple sources such as the electric-magnetic field and gas-solid-thermal interaction, which is becoming a key bottle-neck challenge both scientifically and technologically in improving the machining accuracy. This project aims to address the immediate great challenges in developing core components of ultra-precision micro-cutting manufacturing machines. Focused on the following two key scientific challenges, i.e. 1) the action mechanism of the multiphysics coupling on the thermal behavior of the motorized spindle system and 2) online perception of the state parameters of thermal behavior and active thermal control under condition of multiphysics interaction coupling, this project will carry out interdisciplinary research covering the fundamental theories and key enabling techniques, and reveal the space-time evolvement rules of the thermal behavior of the ultra-high speed and ultra-precision motorized spindle system under condition of multiphysics couplings. This project will also develop the cooling structure innovation design and optimization approach of the spindle system. Furthermore, this project will develop new active thermal control methods based on thermal behavior prediction and online perception of the thermal behavior state parameters, so as to develop the active thermal control system of the ultra-high speed and ultra-precision aerostatic motorized spindle system. Research achievements of this project will supply the fundamental theories and key enabling techniques to facilitate independent R&D capability of high thermal stability, ultra-high speed and ultra-precision aerostatic motorized spindles, and this project is of great significance not only for academic research but also for engineering application.

超高速超精密空气静压电主轴是超精密微切削数控机床实现高精度、高效率和高速度加工的关键功能部件，以空气静压支承和电磁直接驱动为典型结构特征，其热稳定性受电-磁-气-固-热多物理场耦合作用影响，成为制约加工精度提升的瓶颈。本项目面向我国超精密微切削加工装备核心部件的重大需求，围绕多物理场耦合对电主轴系统热行为的作用机理和多物理场耦合作用下热行为状态参量的在线感知及主动控制这两个科学问题，从基础理论和关键技术层面，通过多学科交叉融合，揭示超高速超精密空气静压电主轴系统在多物理场耦合作用下热行为的时空演变规律，构建电主轴系统冷却结构的创新设计与优化机制，提出基于热行为预测和状态参量在线感知的主动热控制新原理，开发超高速超精密空气静压电主轴主动热控制系统，为高热稳定性超高速超精密加工空气静压电主轴的自主研发提供基础理论和关键技术支持，具有重要的学术意义和工程应用前景。

超精密超高速空气静压电主轴以气浮支承和电磁直驱为典型结构特征，其热稳定性受电、磁、气、固、热跨尺度多物理场耦合作用影响，成为制约加工精度提升的瓶颈。本项目面向我国超精密加工装备核心部件的重大需求，围绕跨尺度多物理场耦合对电主轴系统热行为的作用机理和多物理场耦合作用下热行为状态参量的感知及主动控制这两个科学问题，进行了超精密超高速空气静压电主轴的结构设计研究，确定了超精密超高速空气静压电主轴核心部件以及整机的结构方案；采用有限元法数值求解非线性可压缩雷诺方程，推导了含有速度项的雷诺方程有限元形式，开发了空气静压径向轴承和止推轴承性能分析程序，揭示了静压效应、动压效应和动静压混合效应对超高速空气静压径向轴承性能的作用机理，分析了空气静压径向轴承和止推轴承的结构参数对轴承性能的影响规律；研究了空气静压电主轴系统多物理场分析中的电-磁-气-固-热各物理场子模型，基于Isight软件建立了超高速空气静压电主轴系统多物理场集成仿真模型，分析了多物理场耦合作用下电主轴系统稳态温度场和结构热变形等；提出了电主轴系统并联冷却新结构、主动热控制系统及其实施方案；搭建了超精密超高速空气静压电主轴热行为测试实验系统，通过实验研究了空气静压电主轴系统的温度场、结构热变形等特性，验证了本项目建立的空气静压电主轴系统多物理场集成仿真模型的有效性；开展了电主轴系统热控制实验研究，研究了测温传感器的优化布置方案，测试了冷却水的入口温度和流量对电主轴系统不同部位温度的影响规律，优化了电主轴水冷系统的工艺参数。基于上述研究工作，开发了新款高速超精密空气静压永磁同步电主轴原理样机，并进行了相关实验测试。本项目的研究工作为超精密超高速空气静压电主轴的热设计提供了重要的理论和实验数据，为后续超精密超高速空气静压电主轴的系统优化提供了前期技术积累并为超精密超高速空气静压电主轴的市场化应用奠定了坚实的基础。