基于最小位移的磁悬浮转子变极性LMS反馈不平衡补偿  

Variable polarity LMS feedback based on displacement nulling to compensate unbalance of magnetic bearing

作　　者：宋腾[1,2] 韩邦成[1,2] 郑世强[1,2] 冯锐[1,2] 

机构地区：[1]北京航空航天大学惯性技术重点实验室,北京100191 [2]北京航空航天大学新型惯性仪表与导航系统技术国防重点学科实验室,北京100191

出　　处：《振动与冲击》2015年第7期24-32,共9页Journal of Vibration and Shock

基　　金：航空创新基金(2012Z1315);国家自然科学基金资助项目(61203203);国家重大科学仪器设备开发专项(2012YQ040235);北京市科技创新基地培育与发展工程专项项目(J131104002813105)

摘　　要：针对高速电机磁悬浮转子受不平衡扰动时位移精度下降的问题,提出一种基于最小位移原则的变极性最小均方误差(least mean square,LMS)反馈不平衡补偿策略,通过在线辨识位移信号中的转速同频分量,引入反馈补偿来增加系统对同频分量的广义动刚度,实现不平衡补偿。利用广义根轨迹分析了引入补偿后系统的闭环稳定性,同时针对仅以负极性或正极性引入补偿后,闭环系统均存在临界转频以上或以下发散的问题,设计了通过切换引入补偿的极性来穿越临界转频,从而实现引入LMS反馈补偿后全转速范围闭环稳定。实验结果表明,该方法在全转速范围内均能大幅减小位移信号中的转速同频分量。In consideration of the decrease of high-speed motor magnetic rotor displacement accuracy generated by unbalance vibration, a LMS feedback algorithm based on the principle of displacement nulling was proposed. The generalized dynamic stiffness of the system was improved by online identifying the same-frequency component in displacment signal and adding feedback to achieve unbalance compensation. In addition, the stability of close loop system was analyzed by use of generalized root locus; meanwhile, to cross over the critical frequency and achieve the displacement compensation within the whole speed range, a variable polarity strategy was raised. The experiment results demonstrate the method can suppress the displacement same-frequency vibration effectively within the whole speed range.

关 键 词：主动磁悬浮轴承 最小位移 不平衡补偿 变极性LMS反馈 广义根轨迹 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]