针对纸张定量控制的难点 ,提出了一种能用于大时滞过程的自整定 PID/PI控制算法 .通过改进型继电反馈频域响应辨识方法获得实际过程 Nyquist曲线与 S平面负实轴和虚轴交点处等幅振荡的幅值和频率 ,给定幅值裕度和相角裕度鲁棒性能指标 ,确定自整定 PID/PI控制器参数 .此算法具有参数整定简单 ,对实际过程模型的依赖性小 ,鲁棒性强及易于实现等优点 ,适合于含有大时滞的工业过程控制 Aiming at the difficulty of quantitative control of paper, a self-tuning PID / PI control algorithm which can be used in large time-delay process is proposed.The Nyquist curves of actual process and real axis of S-plane and The amplitude and frequency of equal amplitude oscillation at the intersection of imaginary axis and the robust performance index of amplitude margin and phase margin are given to determine the parameters of self-tuning PID / PI controller.This algorithm has the advantages of simple tuning of parameters, Less dependent, robust and easy to implement, etc., suitable for industrial process control with large time delay