基于行为模型的电机动态扭矩测试研究

Research on dynamic torque test of motor based on behavior model

电机动态扭矩一般使用扭矩传感器测量,但扭矩传感器应变片粘贴的角度容易发生改变,且长期使用容易变形,造成测量结果误差较大,无法实现对电机动态扭矩的长期测量。为此,提出一种扭矩传感器行为模型测量扭矩的方案,以直流无刷电机为负载电机,利用标准扭矩传感器测量负载电机的电流和扭矩,通过采用线性回归的方法得到扭矩传感器的行为模型,再利用该模型替代扭矩传感器来测量电机扭矩。该方法克服因扭矩传感器的安装、应变片变形等对扭矩测量精度的影响。基于该方法设计行为模型测量动态扭矩的系统,以750 W永磁同步电机为被测对象,分别使用该系统与使用扭矩传感器方法测试比较,该方法测量动态扭矩时相对扭矩传感器测量的动态扭矩最大相对误差为1.90%,非线性误差为1.84%,重复性误差为0.084%。结果表明:使用行为模型可代替扭矩传感器测量电机动态扭矩,有利于对电机动态扭矩的长期稳定测量,且系统在体积、成本、结构以及操作维护方面都更具优势。

The motor dynamic torque is generally measured with a torque sensor,but the angle of the torque sensor strain gauge is easy to change,and it is easy to be deformed after long-term use,resulting in a large error in the measurement result,which cannot achieve long-term measurement of the motor dynamic torque.To this end,this paper proposes a torque sensor behavior model to measure torque.This scheme uses a DC brushless motor as the load motor,uses a standard torque sensor to measure the current and torque of the load motor,and uses linear regression to obtain the behavior of the torque sensor.Model,and then use this model to replace the torque sensor to measure the motor torque.This method overcomes the influence of torque sensor installation and strain gauge deformation on torque measurement accuracy.Based on this method,a behavior model measuring dynamic torque system is designed.A 750 W permanent magnet synchronous motor is used as the test object.The system is compared with the torque sensor method.The dynamic torque measured by this method is the largest relative to the torque sensor.The relative error is 1.90%,the nonlinear error is 1.84%,and the repeatability error is 0.084%.The results show that the use of behavioral models can replace the torque sensor to measure the dynamic torque of the motor,which is conducive to the long-term stable measurement of the dynamic torque of the motor.Cost,structure and operation and maintenance are more advantageous.