Levy法参数估值的应用研究

 上述实例及其它算例表明,试验数据与理论值偏差1％时,所得估值参数与理论参数的最大相对误差不大于4％,因此,Levy提出的系统辨识方法是有实用价值的。 二、试验频率点数和频率范围对辨识精度影响 Levy法不是无偏估计,增加试验点数,不一定能提高估值精度,还会使系数阵X行数增加,易于导致病态矩阵和试验数据的弱相关,使辨识精度下降,甚至估值参数不可信。

APPLICATION STUDY ON PARAMETER EVALUATION BY THE LEVY METHOD

With the view of practical application the problems occurr ed in the application of the Levy method are considered. They are the perturbation of experimental data, enhancement of accuracy of parameter evaluation, determination of type order of system, identification of high order systems and systems with integration and time-delay elements. Practical examples are analyzed and investigated. In conjunction with prior information, the conclusions drawn and the measures proposed for solution may improve adaptation of the Levy method to engineering practice.