基于时滞系统IMC-PID的设计与整定

Design and Tuning of IMC-PID Based on Time Delay System

时滞系统的控制过程具有较大的时滞性、开环的不稳定性及明显的非线性,需要引进更为先进的控制算法——内模PID控制算法,在设计系统时希望系统性能不会受中间因素的影响。鲁棒性是闭环系统的一个非常重要的性能指标。增益域度和相位域度常为系统鲁棒性的性能指标,但在有些情况下并不能真正表征系统鲁棒性,特别是具有异常频率响应曲线的系统。对于这种系统,灵敏度则能在系统所有频率范围内满足相应的约束条件,因而最大灵敏度也作为闭环系统鲁棒性能指标。通过对时滞系统中内模PID控制中鲁棒性能指标的整定,从而能够较为精确的整定内模PID控制器参数。

The control system with time-delay process has large time lag, open-loop instability and obvious nonlinearity. In the design of controller for time-delay system, it is hoped that the performance of the system will not be affected by intermediate factors, and robustness is a very important performance index of the closed-loop system. Gain and phase domains are often the performance indicators of system robustness, but in some cases,gain and phase domains can not really represent the robustness of the system. Especially for those systems with abnormal frequency response curve, whose sensitivity can satisfy the corresponding constraints in all frequency ranges, so the maximum sensitivity(Ms) is also used as the robust performance index of closed-loop systems.By tuning the robust performance index of internal model PID control in time-delay system, the parameters of internal model PID controller can be more precisely tuned.