基于AIC准则的气动位置控制系统辨识

为了解决气动位置控制系统的精确定位,提出了一种基于AIC准则的气动位置控制系统辨识。通过对气动位置控制系统分析,建立了系统数学模型,并进行了线性化处理。基于AIC准则建立了白噪声和有色噪声两种模型,找到了满足两种模型最小的阶次,采用增广最小二乘法实现对有色噪声参数的无偏估计;通过自相关系数检验了系统残差序列的白色性,验证了气动位置控制系统辨识模型的可靠性。实验结果表明:当幅值分别为1000 A和1200 A时,两种系统的传递函数基本等价,说明在相同阶次的逆M序列且幅值在一定范围内,不同系统对模型参数的辨识影响较小。

System Identification of Pneumatic Position Control Based on AIC Rule

In order to solve the precise positioning of the pneumatic position control system, a system identification method based on AIC rule is proposed. Through the analysis of the pneumatic position control system, the mathematical model of the system is established and is linearized. Two models of white noise and colored noise were established based on AIC rule, and the smallest order that satisfies the two models was found. The unbiased estimation of colored noise parameters is realized by using the augmented least square method. The whiteness of the residual sequence of the system was tested by the autocorrelation coefficient, and the reliability of the identification model of the pneumatic position control system was verified. The results show: When the amplitudes are 1000 A and 1200 A, the transfer functions of the two systems are basically equivalent, which means that in the inverse M sequence of the same order and the amplitude is within a certain range, different systems have little influence on the identification of model parameters.