基于三惯量模型的柔性进给系统建模及仿真

摘要

Aiming at the problem that the control parameters of flexible feed system is difficult to determine, a new method is proposed in this paper. In this method, the flexible feed system of machine tool is modeled based on three inertia model, and the PI parameters for velocity loop are determined using root locus tech-nique and statistical analysis method. The corresponding relation between the control parameters and the characteristic parameters of flexible mechanical transmission system is derived. The simulation results show that:the method can be used to obtain the accurate control parameters through the inertia ratio of the me-chanical transmission system and the first two natural frequencies quickly and effectively and fast and stable response characteristics of the system are obtained; The system response based on the method proposed in this paper is more rapid than the frequency domain method;The calculation process is more simple than u-sing root locus method, and the method is more suitable for real-time online identification and tuning.%针对柔性进给系统速度环控制参数难以精确整定的问题,文章通过建立机床柔性进给系统的三惯量模型,采用根轨迹法和统计分析法对速度环进行了PI参数整定,并根据最短调整时间确定了速度环控制参数与柔性机械传动系统特征参数之间的关系式.仿真实验表明,该方法能够简单有效的通过机械传动系统惯量比和前两阶固有频率得到准确的控制参数,并获得快速、稳定的系统响应特性;依据该方法整定的系统响应比频域法更快速;与根轨迹法整定结果相近,但该方法的计算过程比根轨迹法简单的多,更适用于实时在线辨识和整定.