基于观测器的非线性不确定系统鲁棒故障检测新方法

Novel observer-based robust fault detection method for nonlinear uncertain systems

中文关键词  观测器设计  非线性不确定系统  线性矩阵不等式  统计理论  鲁棒故障检测

英文关键词  observer design  nonlinear uncertain system  linear matrix inequality  statistical theory  robust fault detection

中文摘要

      针对非线性不确定系统的鲁棒故障检测问题, 提出了一种采用统计理论的新方法. 通过设计全阶故障观测器产生残差信号, 将鲁棒故障检测观测器设计问题转化为H∞优化问题; 利用H∞范数描述故障检测的鲁棒性, 保证系统的抗干扰能力, 同时引入H_范数, 确保对故障信号的灵敏度; 应用线性矩阵不等式技术给出了该设计问题解存在的条件和求解方法. 将统计理论用于故障检测阈值的确定, 充分考虑了残差信号的随机特性, 使故障决策更加准确和可靠. 最后通过仿真实例验证了本文方法的有效性.

英文摘要

      For the robust fault detection in nonlinear uncertain systems, we propose a novel method based on the statistical theory. The residual is generated after the full-order fault observer is designed, and the robust fault detection problem is formulated as an H-infinity optimization problem. The robustness of the fault detection is described by H-infinity norm, so the capacity of resisting disturbances is ensured. Besides, the H norm is introduced to ensure the sensitivity to faults. By using the linear matrix inequality techniques, we derive the solvable conditions of this optimization problem and obtain the solutions as well. Statistical theory is used for determining the threshold of the fault detection. Taking account of the randomness of the residual makes the fault detection results more exact and credible. The validity of this proposed approach is illustrated by a numerical example.