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分析了国产快走丝线切割机床加工精度差的运动学和动力学原因。导出了电极丝的运动方程和各种激励下的强迫响应解，指出丝架的振动和转动元件的动不平衡是影响电极丝稳定性和加工质量的主要因素．由于电极丝细而柔，结构振动和动不平衡在制造中难以完全消除，着重研究了利用主动控制方法提高电极丝动态稳定性和加工质量的理论原理和技术方法。通过理论分析，指出主动控制不应采用传统的模态控制，而应为远低于首阶模态的强迫响应控制。在此情况下，检测器和作动器的设置不受振型节点限制．根据这种原理，设计了一种简单的控制系统，利用压电陶瓷元件对电极丝的振动进行间接测量和控制．为此开发了一种基于振动转移的“轻压接触”式测量和控制方法，解决了丝振难以测量和控制的难题．实验结果表明，采用主动控制后电极丝的振幅大大降低，加工质量明显提高．
The kinematic and kinetic reasons for the poor machining precision of the domestic fast-moving wire cutting machine are analyzed. The equations of motion and the forced responses under various stimuli are deduced. It is pointed out that the vibration of the wire frame and the dynamic unbalance of rotating elements are the main factors affecting the stability and processing quality of wire. Due to the thin and soft electrode, the structural vibration and dynamic imbalance can not be completely eliminated in manufacturing. The theoretical principle and technical methods of using active control method to improve the dynamic stability and processing quality of the electrode wire are emphatically studied. Through theoretical analysis, it is pointed out that active control should not adopt the traditional modal control, but should be much lower than the first order modal forced response control. In this case, the detector and actuator settings are not limited by the modeled node. According to this principle, a simple control system is designed to measure and control the vibration of the electrode wire indirectly using the piezoelectric ceramic element. For this reason, a measurement and control method of light pressure contact based on vibration transfer has been developed to solve the difficult problem of measuring and controlling wire vibration. The experimental results show that the amplitude of the electrode wire is greatly reduced after the active control, and the processing quality is obviously improved.