优化直接进给轴伺服参数对提高进给轴抗干扰性能具有重要作用。分析了数控系统中应用伯德图优化伺服参数存在的问题,研究了一种基于动刚度评价的直接进给轴伺服参数优化方法。通过建立直接进给轴动力学模型,给出了基于脉冲激励的动刚度测量方法,依据测量方法确定进给轴动刚度频谱图,建立了直接进给轴伺服系统动刚度模型,分析得到影响动刚度的主要因素,结合动刚度频谱图,给出了伺服参数快速优化策略。优化策略中依据动刚度频谱图判断共振点所在频段,应用电子滤波器抑制共振频段。以驱动系统为SINUMERIK 840D的自构建直线电机进给轴实验平台为对象,进行了伺服参数优化实验,实验结果表明,该方法能有效避免误判共振频段,可直接确认共振点,与应用伯德图优化伺服参数方法相比,优化后使速度环伯德图0dB频段增加58.6Hz,且首个尖峰延后11.7Hz。
The purpose of this paper is to explore a method of tuning servo parameters for direct feed drive, which can finally improve the anti-interference performance of direct feed drive. The main difficulty of using the Bode diagram to tune servo parametersis was that the resonance frequency could not be measured accurately and efficiently. A servo parameter tuning method of direct feed drive was proposed on the basis of dynamic stiffness evaluation. A dynamic stiffness measurement scheme was proposed and verified based on pulse excitation, which was based on the kinetic model of direct feed drive. A dynamic stiffness spectrum diagram might be measured by the measurement scheme which was useful in the tuning strategy. Then,a dynamic stiffness model of direct feed drive was built,which infered the main factors of dynamic stiffness. According to the main factors and the dynamic stiffness spectrum diagram, the fast tuning strategy of servo parameters was concluded. The tuning strategy found the resonance frequency by using the dynamic stiffness spectrum diagram, and inhibited the res- onance frequency by the electronic filter. Finally, an experiment was conducted on a self-construction linear feeding platform servo system of which was ta shows that the method can find the resonance driven by SINUMERIK 840D. The experimental da- frequency directly. Also, the study shows that the 0dB frequency of speed loop increases to 58.6Hz and have a 11.7 Hz-delay compared with the tuning strategy which is on the basis of Bode diagram.