智能消除和恢复保护间隙的新型保护轴承研究

High-speed rotating rotor will drop onto catcher bearing once magnetic bearing of maglev motor fail. As the existence of the protect clearance, rotor severe vibration and shock may lead to catcher bearing failure and equipment damage. This project proposes a set of centering device forming an intelligent catcher bearing system, which can eliminate or recover the protect clearance or cut off the motor drive and magnetic bearing support according to the real-time status of maglev motor. The main work in this project includes: (1) the structure and control integration problems between this catcher bearing system and former maglev motor; (2) the key factors that influence the waning vibration capabilities of this catcher bearing system as well as its eliminating and recovering the protect clearance time; (3) exploring the methods to analyze the kinematics, dynamics, statics, heating and failure pre-judgment of the new catcher bearing system; (4) exploring the methods to realize magnetic bearing system re-suspension after short instability under rotor high-speed rotating state; (5) experimental studies on magnetic bearing failures; (6) optimizing the design of this new catcher bearing system based on the theoretical and experimental results, and proposing the design and service life assessment criterions of this system. The researches of this project can on one hand reduce the vibrations and shocks after rotor drop, ensure the system safety; on the other hand can solve the problem of magnetic bearing system re-suspension after short instability. Then the magnetic bearing reliability can be enhanced and the application prospect in industrial application can be widened.

磁悬浮电机中，磁悬浮轴承一旦失稳，高速旋转转子将跌落到保护轴承上，由于保护间隙的存在，转子剧烈的振动和冲击可能导致保护轴承失效和设备损坏。本项目提出一套定心装置组成智能型保护轴承系统，可根据磁悬浮电机的实时状态来消除和恢复保护间隙，适时切断磁悬浮轴承支撑和电机的驱动。重点研究该套系统与磁悬浮电机在结构和控制上的集成问题；研究影响机构消除和恢复保护间隙所需时间和减振能力的关键因素；探讨系统中各部件的运动学、动力学、静力学、发热以及失效预判断分析的方法；探讨高速下磁悬浮轴承短暂失效后再悬浮的方法；进行磁悬浮轴承失效试验研究；根据理论和试验研究结果优化机构设计，提出该套系统的设计和寿命评估准则。本项目的研究可一方面降低转子跌落所带来的振动和冲击，保证系统安全，另一方面可解决磁悬浮轴承短暂失效后的再悬浮问题，提高磁悬浮轴承的可靠性使其在工业应用中具有更广阔的应用。

磁悬浮电机中，保护轴承起到磁悬浮轴承失稳后临时支撑转子的作用，由于保护间隙的存在，高速旋转的转子跌落后，转子剧烈的振动和冲击可能导致保护轴承失效和设备损坏。本项目提出了一套定心装置组成智能型保护轴承系统，可根据磁悬浮电机的实时状态来消除和恢复保护间隙，适时切断磁悬浮轴承支撑和电机的驱动。对该套系统与磁悬浮电机在结构和控制上的集成问题；影响机构消除和恢复保护间隙所需时间和减振能力的关键因素；系统中各部件的运动学、动力学、静力学、发热以及失效预判断分析的方法；高速下磁悬浮轴承短暂失效后再悬浮的方法；磁悬浮轴承失效试验等方面进行了重点研究。为了深入研究磁悬浮轴承系统中的保护轴承，还对其它相关新型保护轴承进行了理论和试验研究。研究结果表明，所设计的新型保护轴承的性能更为优越，能快速消除保护间隙，间隙消除后，碰撞力合力平均值仅约为转子离心力的一半，能有效地降低转子跌落后所带来的振动和冲击，并能稳定持续支撑转子高速旋转；在消除间隙后，能帮助磁悬浮轴承实现快速再悬浮。本项目的研究在一定程度上提高了磁悬浮轴承的可靠性，使其在工业应用中具有更广阔的应用。