基于永磁联轴器的新型转矩仪设计与分析

摘要

Torque is one of the most important parameters in mechanical transmission systems.Commonlyused torque meters are mostly based on torsion strains.Elastic deformation needs to be accurate,heavily relying on installation accuracy,which results in great costand inconvenience.This paper put forward a novel torque meterbased on ordinary permanent magnetic clutch.The magnetic torque generatedin the air gapbetween the double permanent-magnet rotorsvaries with their relative angular position,and eventually the angle difference can present the torque.In this paper,magnetic circuit of the double-rotor meter was discussed,and the formula of magnetic torque and the angle difference (called Torque-Angle Characteristics) verified the reliability of torque measuring.Also,this paper analyzed the design criteria of the parameters,gave suggestions on the waveforms of the magnetic poles,and finally presented the calculation result of a finite element model.%转矩是动力传动系统中的重要参数之一.目前测量转矩所使用的转矩仪大多应用了弹性元件应变原理.这种转矩仪的制造成本较高,占用空间大,测量结果对安装精度的依赖性较强,难以安装在实际的传动系统中在线测量.文中提出一种基于永磁联轴器的新型转矩仪,其原理是利用永磁联轴器的矩角特性,通过测量内、外两个永磁转子的角位置差值,间接获得转矩数值.通过对转矩仪气隙磁场分析,推导出永磁转矩随内、外转子角位置差值变化的解析表达式,讨论了最大转矩与永磁材料特性、极对数和永磁联轴器尺寸参数的关系.提出通过非均匀磁钢厚度分布获得类正弦波磁动势的设计方法,并通过有限元模型计算了含有谐波磁场情况下的矩角特性,验证了该新型转矩仪用于测量转矩的可行性.