高速精密非圆车削的前馈补偿控制

Feedforward compensation control of high speed and fine noncircular turning

在高速精密非圆车削时，微进给伺服机构的幅值衰减和相位滞后特性会产生较大的刀具轨迹跟踪误差，从而降低加工精度。为了减小刀具轨迹跟踪误差，达到高的加工精度，提出了一种增益—相位前馈补偿控制方法。这种方法不需要精确辨识微进给伺服机构的传递函数，只需测出其幅频和相频特性就可以实现补偿控制。理论分析结果证明，该方法可以大大减小刀具跟踪误差，而不影响控制系统的稳定性。采用增益—相位前馈补偿控制方法所完成的切削实验结果表明，微进给伺服机构的定位精度可以达到±０．０１ｍｍ。

Because of gain attenuation and phase delay of microfeed servo mechanism, large tool tracking errors will be produced and machining accuracy required will be lost during high speed and fine turning of noncircular components. In order to eliminate tool tracking errors and reach a high machining precision, a means of gain phase feedforward compensation control is proposed. The transfer function of microfeed servo mechanism does not need to be identified accurately with the control method, and only the characteristics of gain frequency and phase frequency need to be determined to achieve compensation control. The result of theoretical analysis shows that the method decreases greatly tool tracking errors and has no effect on the stability of control system. Experiments employing the means of gain phase feedforward compensation control show that the position errors of microfeed servo mechanism can be accurate within ±0.01mm.