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Based on a sliding mode control, a multi‐area decentralised load frequency control power system with time‐varying delays and non‐linear perturbations is designed in this study. Due to the destabilising effect of delay on the global system, it is necessary to design a control system to accommodate vast time delays so as to manage the deviation in frequency and interchange power. By taking advantage of the system structure and disturbance bounds, robustness is improved. A sliding surface is designed, and the stability of the corresponding sliding motion is analysed based on Lyapunov–Razumikhin function. A delay dependent decentralised sliding mode control is synthesised to drive the system to the sliding surface and maintain a sliding motion afterwards. The obtained results are applied to a two‐area interconnected power system to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This study presents a novel scheme for the synthesis of first‐order and super‐twisting sliding mode controllers for the robust stabilisation of a class of linear time‐invariant time‐delay systems subject to matched disturbances. Starting from a stability analysis of the system to guarantee that the resulting sliding mode dynamics is asymptotically stable, linear matrix inequality conditions of reduced conservatism are derived by using the Lyapunov–Krasovskii approach. Based on the stability analysis, the sliding mode controllers are synthesised to force the evolution of the closed‐loop system trajectories to converge onto a prescribed sliding surface and to ensure that they remain there for all subsequent time. Unlike existing results, the implementation of the proposed approach does not involve strong requirements on the system structure. A numerical and a practical example along with a comparative analysis prove the effectiveness of the proposal and highlight its benefits. [ABSTRACT FROM AUTHOR]

This study addresses the problem of incipient fault detection and diagnosis for Takagi–Sugeno (T–S) fuzzy systems and explores further results of total measurable fault information residual (ToMFIR). First, T–S fuzzy model is used to describe the global dynamics of a non‐linear system and the model of incipient actuator faults is formalised. Second, based on the ToMFIR, a novel incipient fault detection method is proposed, which removes the assumptions on system structure in some existing work. Further, sliding‐mode observers combined with ToMFIR‐based thresholds are designed for incipient fault isolation. Finally, application results conducted on a high‐speed railway traction device are given to illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

An output‐feedback proportional–integral‐derivative‐type control scheme for the global position stabilisation of robot manipulators with bounded inputs is proposed. It guarantees the global regulation objective avoiding input saturation by releasing the feedback not only from the exact knowledge of the system structure and parameter values, but also from velocity measurements. With respect to previous approaches of the kind, the proposed scheme remains simple while increasing design/performance‐adjustment flexibility. For instance, it does not impose the use of a specific sigmoidal function to achieve the required boundedness but involves a generalised type of saturation functions. More importantly, it is characterised by a very simple control‐gain tuning criterion, the simplest hitherto obtained in the considered analytical context. Experimental tests on a 2‐degree‐of‐freedom direct‐drive manipulator corroborate the efficiency of the developed scheme. [ABSTRACT FROM AUTHOR]