Stabilization of Switched Linear Systems With Quantized Output and Switching Delays

Summary This work considers the sliding mode control problem of a class of discrete‐time uncertain switched systems subject to detecting‐delay on mode signals, which may result in the asynchronous phenomenon between the controller and the switched system. Since the mode information of the controlled system is not available for the controller in time, a mode‐independent sliding surface will be introduced, by which an asynchronous sliding mode controller is designed, whose control gain and robust parameter will be changing according to the controller mode. In the analysis on the stability of the closed‐loop control system and the reachability of the specified sliding surface, the asynchronous characteristics are detailedly investigated. It is shown that the Lyapunov function may be not always decreasing along the state trajectories during the unmatched interval of controller modes and system modes. Nevertheless, it is proven that the state trajectories can be driven into a sliding region around the specified sliding surface in finite time. Finally, some numerical simulation results are provided.

Section: The Exponentially Stabilitymentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Sliding mode control of discrete‐time switched systems subject to mode delays

Zhao

Niu

2019

“…(i) The quantizer may reach saturation because of the abrupt system switches, disturbances, and state estimation errors. (ii) The time-triggered update policy of quantizer provided in other works [13][14][15][16]18,20,21 becomes inefficient because, in the presence of switches and disturbances, the explicit calculation of time period between any two updates is hard and conservative. (iii) The online detection of quantizer saturation is expected to avoid due to its drawbacks and the disturbance can lead to nonzero steady-state errors as obtained in the aforementioned works.…”

Section: Introductionmentioning

confidence: 99%

Stabilization of switched nonlinear systems with dynamic output quantization and disturbances

Lian

2020

Summary This paper studies the problem of quantized output feedback stabilization for a disturbed discrete‐time switched system. With the quantized output measurement, an extended state current estimator is constructed to estimate the state and disturbance. In the presence of switches and disturbances, the design of quantization scheme becomes a big challenge to avoid the quantizer saturation and guarantee the control precision. In this setup, the well‐applied time‐triggered method to design the update policy of dynamic quantization parameter is hard to implement. We solve the above problem by proposing a novel event‐triggered update policy of quantization parameter, by which the quantizer update is adaptive to the switching signal and the bound of disturbance difference. Consequently, the quantizer saturation is avoided and, combined with the designed dwell‐time switching law, the system state can converge to the origin. The proposed method is illustrated by a numerical example.

“…Quantized feedback control has drawn wide public concern over the past few decades due to its theoretical and practical importance in the study of mechanical systems, networked control systems, switched systems, and hybrid systems . For quantized feedback control systems, due to limited capacity or security constraints on the communication, the control signal is quantized before transmitting to the plants .…”

Section: Introductionmentioning

confidence: 99%

Quantized feedback control for nonlinear feedforward systems with unknown output functions and unknown control coefficients

Wang

Sun

2019

Summary This paper investigates the quantized feedback control for nonlinear feedforward systems with unknown output functions and unknown control coefficients. The unknown output function is Lipschitz continuous but may not be derivable, and the unknown control coefficients are assumed to be bounded. To deal with this challenging quantized control problem, a time‐varying low‐gain observer is designed and a delicate time‐varying scaling transformation is introduced, which can avoid using the derivative information of the output function. Then, based on the well‐known backstepping method and the sector bound approach, a time‐varying quantized feedback controller is designed using the quantized output, which can achieve the boundedness of the closed‐loop system states and the convergence of the original system states. Moreover, a guideline is provided for choosing the parameters of the input and output quantizers such that the closed‐loop system is stable. Finally, two simulation examples are given to show the effectiveness of the control scheme.