预测PI控制系统的根轨迹分析  

Root Locus Analysis of Predictive PI Control Systems

作　　者：董宇[1] 

机构地区：[1]华南师范大学计算机学院,广东广州510631

出　　处：《计算技术与自动化》2007年第3期70-73,共4页Computing Technology and Automation

摘　　要：研究预测PI控制器的根轨迹。根据根轨迹的性质,当存在模型失配时,较小的期望闭环时间常数将导致控制器的输出产生振铃现象。可以通过增大期望闭环时间常数来消除振铃现象。此外,通过根轨迹法,推导出存在增益失配时,预测PI控制系统的稳定性判据。根据稳定性判据,当期望闭环时间常数增大时,增益稳定区间随之而增大;当模型时滞增大时,增益稳定区间随之而减小。数值仿真结果验证了上述结论。The root locus of the predictive PI controller is investigated in detail, Based on the root locus properties, small desired closed - loop time constant may result in ringing in the presence of plant model mismatches. Ringing can be eliminated by increasing the desired closed- loop time constant, A stability criterion for the predictive PI control system in the presence of process gain variations is derived. According to the stability criterion, the stability gain interval extends as the desired closed-loop time constant increases. Furthermore, the smaller the time delay of the plant is, the larger the stability gain interval is, Numerical examples verified the conclusions.

关 键 词：根轨迹 预测PI控制 稳定性 时滞 

分 类 号：TP271[自动化与计算机技术—检测技术与自动化装置]