In this article, the problem of reduced‐order observer‐based controller design for a class of nonlinear time‐delay systems is addressed. First, we present sufficient conditions for the existence of the reduced‐order observer of nonlinear time‐delay systems. Then, a state feedback controller is designed to stabilize the systems. Furthermore, it is shown that the separation principle holds for stabilization of the systems based on the reduced‐order observer‐based controller. When the nonlinear part of systems satisfies the quasi‐one‐sided Lipschitz condition, the reduced‐order observer and feedback controller can be designed separately even though the parameter (A, C) of systems is not detectable and parameter (A, B) is not stabilizable. Finally, a numerical example is presented to show the effectiveness of the proposed approach.

中文翻译：

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具有时滞的拟单面Lipschitz非线性系统的降阶基于观测器的控制器设计

本文解决了一类非线性时滞系统基于观测器的降阶控制器问题。首先，我们为非线性时滞系统的降阶观测器的存在提供了充分的条件。然后，设计一个状态反馈控制器来稳定系统。此外，证明了分离原理对于基于降阶基于观察者的控制器的系统的稳定有效。当系统满足的非线性部分的准片面Lipschitz条件，降阶观测器和反馈控制器可以分别设计即使参数（甲，  Ç）的系统是不可检测的和参数（甲， B）是不稳定的。最后，给出了一个数值例子，说明了该方法的有效性。