基于二阶滑模观测器的连续系统故障估计

针对传统的滑模观测器在实现故障估计时带来的抖振问题，设计基于super-twisting算法的二阶滑模观测器以稳定地估计出故障。针对以往利用几何或齐次性方法证明super-twisting算法稳定性过程繁琐的缺点，采用Lyapunov函数来证明稳定性。给出的故障估计结果克服了传统的滑模观测器在估计故障时带来的时延或引进新参数等缺点。最后，将所提出的方法应用于某型飞控系统，结果表明了所提出方法的有效性。

Fault estimation of continuous-time systems based on second order sliding mode observation

For the chattering problem in the fault estimation using the traditional sliding mode observation, the second order sliding mode observation based on the super-twisting algorithm is designed to estimate the fault stably. In order to avoid the cumbersome process of proving the stability of the super-twisting algorithm using the geometric method or the homogeneity, a Lyapunov function is adopted to prove the stability of the super-twisting algorithm. The given fault estimation result can be calculated on-line. Moreover, the result overcomes the drawbacks of introducing the delay or the new parameter caused by the traditional methods. Finally, the proposed method is applied to a certain type of flight control systems, and the results show its effectiveness.