非线性度变换的描述函数法分析

摘要

在误差信号上进行幂指数变换的非线性度变换在许多应用中有利于提高控制系统的控制品质.进一步对其描述函数特性进行了分析，并利用奈奎斯特判据对系统添加非线性度变换后的稳定性进行了判断.结果表明，利用非线性度变换不仅可有效地使部分不稳定系统变为稳定，而且普遍地提高了控制系统的控制品质，从理论上验证了非线性度变换在部分控制系统中的有效性，为非线性度变换的具体设计提供了依据.%Presents the analysis of the property of the describing function to improve the quality of the control system in many applications by using the nonlinear norm transform of exponent index of the errors, and the use of Nyquist theory to evaluate the stability of the nonlinear system with nonlinear norm transform added, and points out that the nonlinear norm transform can not only make some unstable systems stable effectively, but also improve the quality of the control system generally and therefore justifies the validity of nonlinear norm transform on some unstable systems providing the basis for the design of nonlinear norm transform.