PID控制器的性能监控与评估  

Performance monitoring and assessment for PID controller

作　　者：刘小艳[1] 张泉灵[1] 苏宏业[1] 

机构地区：[1]浙江大学工业控制技术国家重点实验室,浙江大学智能系统与控制研究所,浙江杭州310027

出　　处：《计算机与应用化学》2010年第1期91-94,共4页Computers and Applied Chemistry

基　　金：国家高技术研究发展计划863计划资助项目(2007AA04Z172)

摘　　要：为了解决目前工业系统中普遍使用的PID控制器由于工况变化等原因引起的系统发生时变而导致所在回路PID控制器性能可能下降的问题,本文提出了一种专门针对PID控制器进行性能评估、优化及监控的方法,即:PID循环评估优化算法。该算法利用系统闭环输入输出数据,使用基于MVC(minimum variance control)的PID最小方差准则,来对PID控制器的性能进行评估,并且计算出在最小方差意义下最优PID控制器参数;评估过程结果与现实系统输出方差进行比较,做为PID参数在线优化的判断依据,当现实系统性能低于某一标准的时候对控制器进行优化处理。在整个算法中,通过输入输出数据的处理与判断,利用评估优化后的PID参数对系统进行控制,并再次回到最初的输入输出数据的处理和判断过程,实现在控制过程中的系统性能监控。本文的计算机仿真试验验证了该方法的有效性,由图可看出,系统发生渐变和突变后,当输出方差超过了程序限定的标准时,在1 300秒内系统能自动评估并施行优化而达到稳定。该循环评估优化算法现实了在对系统进行性能评估监控的同时,能按照一定条件作为标准对系统的PID参数进行优化,最终使得系统具有自我监控评估和自我优化的能力,此方法能在特定的工况下进行应用。In order to resolve the problem that a PID controller performance may decrease when the operating conditions changes if the system condition changes.This paper presents a special performance evaluation for the PID controller,optimization and control approach,namely：PID loop evaluation and optimization algorithms.The algorithm uses the system closed-loop input and output data,assesses PID controller performance according to MVC（minimum variance control）benchmark,finds the optimized PID parameters for the time-varying systems at the base of MVC;the assessment process The results with the real system output variance to compare PID parameters on-line optimization as a basis for judgments,when the actual system performance below a.certain standard time of the controller optimization.The assessment process will take the new output variance to compare with the real system output variance,the result become the basis for judgments.When the actual system performance below a certain standard,the algorithms will change the PID parameters as a optimization process.At the whole algorithm,the monitoring of input and output data lasting in the whole process become a monitoring for the PID control system.Simulation results show the validity of this method.In the context,if the system have a abrupt or gradual changing,the system can automatically evaluate and optimize the implementation to achieve stability after 1300 seconds.The cycle of evaluation and optimization algorithm for realistic performance can assess and monitor the system at the same time.with certain conditions,with a certain standard this algorithm can optimize the PID parameters and ultimately make the system have the selfmonitoring and selfassessment capacity.

关 键 词：时变系统 PID 性能评估 在线优化 

分 类 号：TP273[自动化与计算机技术—检测技术与自动化装置]