高速、超高速转子非介入逆向动态平衡分析方法研究

Rotors with high speed and ultra-high speed are one of the most important objects in the modern mechanical equipment development. This project aims at the basic common key issue concerning the operation precision and stability control of this kind of rotors – study on the dynamic balancing method. Through the in-depth analysis of the deficiencies of the current balancing technique, this project tries to explore a holistic solution to the dynamic balancing problem of rotors with high speed and ultra-high speed. The related analysis is fully based on the real collected unbalance response and is implemented through the combination of theoretical modeling and experimental verification. A mode decoupling method is put forward to solve the uncertainty problem brought by the time-varying characteristic of rotor mode shape through the dynamic property verification of the analytical mode extracted from the shaft mode shape and the operational deflection shape (ODS). Then the construction method for the nonlinear modal decomposition equations is provided. Through the inverse optimization of the equations the nonlinear weighted function, which contains the important information about rotor mass unbalance distribution characteristic, is identified quantitatively. This way of inverse solution of the modal decomposition equations makes the balancing analysis under nonlinear unbalance response condition practical. Based on that, the complex modal transfer matrix is constructed by a non-invasive analysis method, which realized the identification of rotor system dynamic parameters without trial runs. Finally, the non-invasive inverse dynamic balancing method for rotors with high speed and ultra-high speed will be formed. The study of this project is of great scientific significance and practical value to the operational precision and stability control.

高速、超高速转子是机械装备发展的重要方向之一。本课题针对其运行精度和稳定性控制涉及的关键共性基础问题-动态平衡分析方法-展开研究。通过对现有平衡方法存在问题的深层分析，探索高速、超高速转子动态平衡分析问题的整体解决方案。研究以实测不平衡响应信号为分析依据，采取理论建模分析结合实验验证的方式进行。首先，提出一种转子时变振型解耦分析方法，并通过对分析振型的平衡关联动力学性质检验，拟解决振型时变性给平衡分析带来的不确定性问题；其次，提出转子ODS分析振型非线性模态分解方程的构建方法并通过非线性模态权函数的逆向优化求解，以实现在不平衡响应非线性条件下的不平衡分布模式逆向辨识；以及在此基础上，整合出一种复模态迁移矩阵的非介入构建方法，实现转子特征响应的无试重获取，最终形成适用于高速、超高速转子的非介入逆向动态平衡分析方法。项目的研究成果将对高速、超高速转子运行精度及其稳定性控制具有重要的科学意义。

本课题重点围绕转子-轴承系统运行精度和稳定控制中涉及的若干关键问题进行了深入的研究。课题首先重点针对转子系统的动态平衡分析方法进行了研究。在全息谱多信息融合理论的基础上分析了ODS振型的时变性和空间分布特性及其成因。通过对ODS振型的解耦提取了ODS分析振型，并对其转子平衡状态关联动力学性质进行了检验。进而通过对复模态迁移矩阵的非介入逆向构建，形成了转子非介入逆向动态平衡分析方法。在围绕转子-轴承系统中的核心部件-滚动轴承-的故障诊断方法研究工作中，课题针对目前轴承故障信号存在信噪比低、外部干扰成分复杂、特征微弱等难点，研究构建了两种不同的轴承故障特征指标-冲击脉冲指标SPI和频域多点峭度FDMK-并成功应用于轴承故障诊断。对仿真信号和实测故障信号的分析结果表明，SPI和FDMK具备较强的抗复杂干扰的能力，可用于微弱故障特征的检测和早期故障的诊断。