磁-球轴承复合支撑电主轴振动特性分析

Vibration characteristics analysis of motorized spindle system using magnetic-ball bearing composite support

为提高电主轴系统刚度和抗振能力,提出一种由磁悬浮轴承和角接触球轴承共同支撑的复合支撑电主轴,通过球轴承保证主轴系统刚度,引入磁轴承控制系统对主轴振动进行抑制,实现电主轴系统在球轴承低预紧状态下仍具有较好的动态性能。基于ANSYS模态分析、谐响应分析和瞬态动力学仿真,分析了不平衡质量引起的振动响应,比较了磁-球轴承复合支撑电主轴和球轴承支撑电主轴的振动特性。搭建复合支撑电主轴试验平台,对该复合支撑电主轴进行振动特性测试与分析。结果表明,复合支撑电主轴与球轴承支撑电主轴相比,复合支撑系统可以有效提高转子的临界转速、降低转子的振动幅值和球轴承应力,使电主轴具有较高的动态刚度。

Here,to improve stiffness and anti-vibration capability of motorized spindle system,a motorized spindle with composite support of magnetic bearing and angular contact ball bearing was proposed.The spindle system stiffness was ensured by ball bearing,and magnetic bearing control system was introduced to suppress spindle vibration to realize the motorized spindle system having better dynamic performance under the condition of ball bearing with low preload.Based on ANSYS modal analysis,harmonic response analysis and transient dynamic simulation,vibration responses caused by unbalanced mass were analyzed,and vibration characteristics of motorized spindle with magnetic-ball bearing composite support and motorized spindle with ball bearing support were compared.A composite support motorized spindle test platform was built to conduct vibration characteristics testing and analysis for the composite support motorized spindle.The results showed that compared to motorized spindle with ball bearing support,the motorized spindle system with composite support can effectively increase rotor critical speed,reduce rotor vibration amplitude and ball bearing stress,and make itself have higher dynamic stiffness.