Qishui Zhong

Finite-time boundedness of state estimation for neural networks with time-varying delays

In this paper, we study the finite-time boundedness problem for neural networks with time-varying delays. By introducing a newly augmented Lyapunov-Krasovskii functional and considering the relationship between time-varying delays and their upper delay bounds, sufficient condition of state estimation for neural networks with time-varying delays is presented and proved by using convex polyhedron method and novel activation function conditions. Finally, a numerical example is given to illustrate the efficiency and less conservative character of the proposed method.

Stochastic finite-time boundedness for Markovian jumping neural networks with time-varying delays

Abstract In this paper, a novel method is developed for the finite-time boundedness of Markovian jumping neural networks with time-varying delays. By introducing a newly augmented stochastic Lyapunov–Krasovskii functional and novel activation function conditions, sufficient condition for Markovian jumping neural networks is presented, and the state trajectory remains in a bounded region over a pre-specified finite-time interval. Finally, numerical examples are given to illustrate the efficiency and less conservative of the proposed method.

Finite-time boundedness filtering for discrete-time Markovian jump system subject to partly unknown transition probabilities.

This paper investigates the problem of finite-time boundedness filtering for discrete-time Markovian jump system subject partly unknown transition probabilities. By using the multiple Lyapunov function approach, a novel sufficient condition for finite-time bounded of H∞ filtering is derived and the system trajectory stays within a prescribed bound during a specified time interval. Finally, an example is provided to illustrate the usefulness and effectiveness of the proposed method.

Delay-dependent finite-time boundedness of a class of Markovian switching neural networks with time-varying delays

In this paper, a novel method is developed for delay-dependent finite-time boundedness of a class of Markovian switching neural networks with time-varying delays. New sufficient condition for stochastic boundness of Markovian jumping neural networks is presented and proved by an newly augmented stochastic Lyapunov-Krasovskii functional and novel activation function conditions, the state trajectory remains in a bounded region of the state space over a given finite-time interval. Finally, a numerical example is given to illustrate the efficiency and less conservative of the proposed method.

Finite-time H ∞ control of a switched discrete-time system with average dwell time

For switched discrete-time systems, switching behavior always affects the finite-time stability property, which was neglected by most previous research. This paper investigates the problem of H∞ control for a switched discrete-time system with average dwell time. Based on the results on finite-time boundned and average dwell time, sufficient conditions for finite-time bounded and finite-time H∞ control under arbitrary switching are derived, and the closed-loop system trajectory stays within a prescribed bound. Finally, an example is given to illustrate the efficiency of the proposed method.

State of charge estimation of lithium-ion batteries using fractional order sliding mode observer

This paper presents a state of charge (SOC) estimation method based on fractional order sliding mode observer (SMO) for lithium-ion batteries. A fractional order RC equivalent circuit model (FORCECM) is firstly constructed to describe the charging and discharging dynamic characteristics of the battery. Then, based on the differential equations of the FORCECM, fractional order SMOs for SOC, polarization voltage and terminal voltage estimation are designed. After that, convergence of the proposed observers is analyzed by Lyapunovs stability theory method. The framework of the designed observer system is simple and easy to implement. The SMOs can overcome the uncertainties of parameters, modeling and measurement errors, and present good robustness. Simulation results show that the presented estimation method is effective, and the designed observers have good performance.

Robust mode-dependent control for discrete-time singular Markovian jump systems with time-varying delay

AbstractThis study investigates the problem of robust mode-dependent control for a class of discrete-time singular Markovian jump systems with time-varying delay. Using the Lyapunov functional method and delay decomposition approach, Linear matrix inequality (LMI)-based sufficient conditions for the stochastic stability and robust mode-dependent control are developed, which guarantee the considered systems to be regular, causal and stochastically stabilisable. Finally, numerical examples are presented to demonstrate the effectiveness and advantages of the theoretical results.

An approach for SOC estimation based on sliding mode observer and fractional order equivalent circuit model of lithium-ion batteries

A state of charge (SOC) estimation method based on sliding mode observer (SMO) and fractional order equivalent circuit model (FOECM) of lithium-ion batteries is presented. A fractional order equivalent circuit model was applied to model the lithium-ion battery and the sliding mode observers were designed to compensate the errors and uncertainties which are caused by the model in modeling. The convergence of the sliding mode observer is guaranteed by the Lyapunov inequality equation. The results of simulation experiment for the presented approach show the proposed method can estimate the SOC efficiently and accurately with good performance.

Estimating the state of charge of lithium batteries based on fractional-order sliding-mode observer

This paper considers estimating the state-of-charge (SOC) for lithium-ion batteries, that utilizes a fractional-order (FO) sliding-mode observer (SMO) is investigated. The capacity loss and deterioration resistance can be estimated by the FO SMO. Based on Mittag-Leffler stability theory, the FO SMO is designed and analyzed. The convergence property about FO SMO is shown by utilizing the Lyanunov-Krasovskii function. A key analysis technique is enabled by proposed a fundamental boundedness lemma. The proposed method is easily applied to SOC in order to illustrate robust control properties against systems errors. The simulation examples are used to illustrate effectiveness of the proposed control scheme.

Finite-time H ∞ Open image in new window control of a switched discrete-time system with average dwell time

For switched discrete-time systems, switching behavior always affects the finite-time stability property, which was neglected by most previous research. This paper investigates the problem of H∞ control for a switched discrete-time system with average dwell time. Based on the results on finite-time boundned and average dwell time, sufficient conditions for finite-time bounded and finite-time H∞ control under arbitrary switching are derived, and the closed-loop system trajectory stays within a prescribed bound. Finally, an example is given to illustrate the efficiency of the proposed method.