基于动态电磁力的主动式动平衡测量方法的研究

Research of active dynamical balance measurement method based on dynamic electromagnetic force

动平衡机在测量大质偏类工件时,由于不平衡量较大,振动信号往往会超出测量系统的线性范围而造成测量误差偏大。为了提高动平衡测量精度,提出了一种采用电磁力产生的同频振动抵消大部分初始振动,从而减小簧板振动量,保证系统线性度的动平衡测量方法。讨论了该方法的基本工作原理,建立了电磁力装置的磁路模型;采用有限元建模对电磁力的可控性进行了研究,并分析了气隙、温度等因素对电磁力的影响;最后介绍了测量控制系统和控制策略。动平衡测量实验表明,该测量方法能够有效地提高大不平衡量工件的动平衡测量精度。

When dynamical balance machine is used to measure the imbalance of the workpiece with large eccentric mass,due to the large imbalance the vibration signal usually exceeds the linear range of both the dynamical balance machine and measurement system,which results in grave error. In order to improve the accuracy of imbalance measurement,a method is proposed,which utilizes a controllable electromagnet to generate controllable electromagnetic force for attenuating the unbalance vibration synchronously,so as to avoid the vibration signal exceeding the liner range. The basic operation principle of the method is discussed,the equivalent magnetic circuit model of the electromagnet is established,and the relationship between the coil current and dynamic electromagnetic force is analyzed with finite element modeling. The influence of some factors,such as air gap and temperature on electromagnetic force is analyzed. The control system and control strategy are also introduced. Dynamical balance test experiment was conducted,the test results indicate that the proposed measurement method can effectively improve the dynamical balance test accuracy of the workpiece with large eccentric mass.