输入输出采样周期相同,而且时间上同步的传统离散时间系统(即单率系统)最小方差控制方法,不适用于输入输出采样周期不相同的双率系统。提出了控制刷新频率是输出采样频率整数倍的未知参数双率系统最小方差自校正控制算法。其基本思想是,通过设计一个参数估计器来估计系统模型参数,设计一个损失输出估计器来计算系统的损失输出(即采样间输出),通过Diophantine方程和极小化最优预测误差方差导出了双率系统最小方差控制律,并提出了最小方差自校正控制算法。最后用仿真例子说明提出方法的有效性。
The minimum variance (MV) control for the traditional discrete-time systems (namely, single-rate systems) with the same input and output synchronically sampling periods is not suitable for dual-rate systems with different input and output sampling periods. The MV self-tuning control methods for dual-rate systems with unknown parameter and with the input updating period equaling the integer multiple of the output sampling period were proposed The basic idea is to design an estimator to identify the system parameters, and to design an estimator to compute the missing outputs (i.e., inter-sample outputs), both using dual-rate input and output data, and to derive the MV control laws for dual- rate systems by using the Diophantine equation and minimizing the variance of the optimal prediction errors, and then to propose the MV self-tuning control algorithms. Simulation example shows that the proposed algorithms are effective.