Bumpless Transfer Control Research Articles

Dwell-Time-Dependent ${H_\infty }$ Bumpless Transfer Control for Discrete-Time Switched Interval Type-2 Fuzzy Systems

This article investigates the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">${H_\infty }$</tex-math></inline-formula> bumpless transfer control problem for a class of discrete-time switched interval type-2 (IT2) fuzzy systems subject to dwell-time constraint. We proposed a novel description of bumpless transfer performance for discrete-time switched IT2 fuzzy systems. With the aid of the dwell-time-dependent Lyapunov function approach and a novel mixed switching strategy, sufficient conditions ensuring the asymptotic stability with an <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">${H_\infty }$</tex-math></inline-formula> bumpless transfer performance are derived. More incisively, the bumpless transfer performance in this article is only required over the subintervals of the active interval, which is more general and relaxes the limitation of traditional bumpless transfer performance in the existing results. Besides, dwell-time-dependent bumpless transfer IT2 fuzzy controllers are designed in the form of linear matrix inequalities. Finally, a single-link robot arm model is employed to demonstrate the potential and effectiveness of the derived theoretical results.

Finite‐time event‐triggered bumpless transfer control for switched systems

AbstractThis study centers on the issue of finite‐time event‐triggered bumpless transfer (BT) control of switched systems. The aim is to suppress the undesirable control jumps at both switching and triggering time, and guarantee the finite‐time stability of switched systems. First, the property of BT is described from its original intention. Then, by co‐design of an improved switching function, an event‐triggered strategy combined with a series of controllers to achieve this objective. Also, the Zeno behavior is excluded. Further, a criterion to guarantee the BT property and the finite‐time stability under event‐triggered mechanism is established. Finally, a turbofan engine control system is taken as an example to testify the validity of the presented control scheme.

Finite‐time input L2 bumpless transfer control for switched systems with its application to aircraft model

SummaryThis article addresses the finite‐time (FT) input bumpless transfer (BT) control problem for switched systems. First, the performance of the input BT is described, quantifying the energy difference caused by the input signal jumps. The objective is to suppress large jumps during switching. Second, a sufficient evidence is established through the multiple Lyapunov functions method to ensure that the switched systems satisfy both the FT property and input BT performance. Also, this evidence allows that the control issue may not be addressed by subsystems. Then, a switching controller and a switching rule are simultaneously constructed for purpose of addressing the issue of the FT input BT control for switched systems. Finally, an effective validation of the established control method is verified by an ‐18 aircraft model simulation.

Robust H2 output-feedback bumpless transfer control of polytopic uncertain LPV systems

The problem of Robust Switching Gain-Scheduled Output-Feedback (RSGSOF) H2 controller synthesis with control bumps limitation is tackled in this paper for polytopic uncertain continuous-time linear parameter varying (LPV) systems. The presented robust switching gain-scheduled control design scheme overcomes the limitation of existing methods based on single quadratic Lyapunov function. However, in practice, RSGSOF controller leads to expressive discontinuities at switching instants. Hence, we aim to investigate of H2 output-feedback Bumpless Transfer Controller (BTC) design problem. In this study, not only stability and an upper bound on the H2-norm performance of the closed-loop system can be guaranteed but also solvability conditions are incorporated in the synthesis procedure to reduce control bumps. The proposed BTC composes multiple LPV controllers with the bumps limitation objective and a Lyapunov-based min-switching rule governing the switching among these controllers. Numerical studies demonstrate the effectiveness of the proposed approach.

Asynchronous bumpless stabilisation of uncertain switched linear positive systems with mixed time delay and L1‐gain performance

This paper investigates a bumpless transfer control problem for uncertain switched positive linear time-delay systems (SPLTDSs) with discrete and distributed delays. The innovation of this study is to develop a linear feedback controller and design a switching law that ensures lower controller signal bumps due to the switches of the SPLTDSs and also guarantee the L 1 –gain performance of the system. To this end, a bumpless transfer performance is proposed, and stabilisation constraints for SPLTDSs with synchronous switching are developed. Dwell time criteria are utilised in the stability analysis. Also, the results are improved to cover the uncertain SPLTDSs with interval or polytopic uncertainties. Then, asynchronous switching is considered, and the proposed method is extended to deals with asynchronous switching mode. Asynchronous switching means switches of the controller have lagged behind the subsystem switches. All the stability conditions are derived by multiple co-positive Lyapunov–Krasovskii functional for synchronous and asynchronous switching conditions. At last, two numerical examples are presented to show the effectiveness of the proposed method compared with the leading existing solutions.

A single and double closed-loop compound anti-sway control method for double-pendulum bridge cranes locating at random position

In the assembly workshops of some heavy special equipment, the bridge cranes for payload lifting often needs to be located frequently. However, the locating position is often determined by the operator, which is random and results in significant payload oscillation and difficulties in trolley positioning. Furthermore, in practice, the bridge crane always exhibits more complicated double-pendulum dynamics compared with single-pendulum crane. To solve these problems, this paper establishes the double-pendulum model of bridge crane. Derived from the proportional-derivative (PD) control, the single closed-loop is designed based on the hook oscillation during acceleration and transporting; when locating, the double closed-loop is presented by utilizing the position and the hook oscillation. Combining the two control methods, a single and double closed-loop compound anti-sway control (SDCAC) method for the bridge crane is proposed. On this basis, to improve the performance of the SDCAC system, the sequential quadratic optimization (SQP) method is adopted to optimize PD parameters. Besides, a novel bumpless transfer control method is proposed to realize the smooth transition between the two control modes. Finally, the simulations and experiments are conducted. The results demonstrate the effectiveness of the proposed method.

State Bumpless Transfer Control for a Class of Switched Descriptor Systems

This paper studies stability for a class of switched descriptor systems with state bumpless transfer performance and input bumpless transfer performance. Since the state jump is inevitable for switched descriptor systems when a switching occurs, to restrain the amplitude of the state jump induced by switchings, for the first time, the state bumpless transfer performance of switched descriptor systems is defined. Moreover, when switching occurs, to avoid the abrupt and large control input signals change damaging the system, we are the first to introduce the input bumpless transfer control scheme for switched descriptor systems. Furthermore, by using multiple Lyapunov functions, a sufficient condition is put forward to make sure the state bumpless transfer performance, input bumpless transfer performance and asymptotical stability for the closed-loop systems. Meanwhile, the switching rule and the state feedback controller are co-designed. In the end, a multiple inputs numerical example and an application on the DC motor model are used to exhibit the merit and validity of the presented control scheme.

Almost output regulation for switched linear systems with bumpless transfer control under destabilizing behaviors

Almost output regulation for switched linear systems with destabilizing behaviors, which means that the almost output regulation problems of all subsystems are unsolvable and some switching instants are unstable with finite increments of the Lyapunov function, is investigated based on the bumpless transfer control. Switching instants with decrements and increments of the Lyapunov function are described as stable and unstable switching instants respectively. Firstly, a hybrid average dwell time strategy is proposed to restrict the occurrence ratio of unstable/stable switching instants and reasonably arranges the number of stable switching instants to offset the increment of the Lyapunov function caused by unstable switching instants and insolvabilities of the involved problem for all subsystems. Then, by interpolating the gains of adjacent controllers within the minimum dwell time, a dynamic error feedback controller with bumpless transfer property is designed to suppress the control bumps induced by controller switchings. Finally, a numerical example is given to demonstrate the effectiveness of the proposed method.

Bumpless stabilisation of uncertain switched positive linear systems under synchronous and asynchronous switching

This paper deals with stabilising uncertain Switched Positive Linear Systems (SPLSs) with a bumpless transfer controller. The contribution of this study is to improve switching controller robustness at the switching instances and also guarantee the –gain performance of the positive systems. Positive systems are widespread; most of the biological, economic systems, disease, etc., have nonnegative variables belonging to this class of systems. Positive Systems modelling encounters different types of uncertainties; therefore, stability analysis and stabilisation of uncertain SPLSs are crucial in analysing positive systems. The stability of the SPLSs can be guarantee by using multiple copositive Lyapunov functions with the Dwell Time (DT) strategy. The stability of the SPLS has been investigated under synchronous and asynchronous switching modes. The so-called asynchronous switching means that the switches between the candidate controllers and system modes are asynchronous. Also, the –gain performance of the system is derived. Finally, two illustrative examples are provided to demonstrate the proposed scheme’s effectiveness compared with the foremost existing solutions.

Bumpless Transfer Control for Switched Linear Systems and its Application to Aero-Engines

To avoid the bumps of the control signal in the switching instants, this paper proposes a bumpless transfer control method which guarantees the continuous of control signal while keeping the asymptotic stability of the closed-loop system. Firstly, the presented bumpless transfer control method possesses a simple structure and meanwhile not have to redesign sub-controllers, which is easy to implement. Furthermore, the method is appropriate for either stable subsystems or unstable subsystems, and be suitable for either state feedback control or dynamic output feedback control. Moreover, we give the sufficient conditions of asymptotic stability for switched linear systems under bumpless transfer control for four cases. For the original switched system with stable subsystems under state or dynamic output feedback control, the stability conditions under mode-dependent average dwell time switching are derived. For the original switched system with unstable subsystems under state or dynamic output feedback control, which is stabilized by some certain switching laws, the stability conditions under the original switching law are given. Finally, a hardware-in-the-loop simulation of an aero-engine control system is employed to verify the effectiveness and superiority of the proposed method.

Bumpless Transfer Control for Gas Turbine

This paper mainly studies a bumpless transfer controller which can be applied to a certain gas turbine. Due to the requirements of low exhaust emission and high combustion efficiency, the gas supply system of the gas turbine is composed of duty fuel, master fuel, and secondary fuel, which inevitably lead to the switching problem in the control system. In order to solve this problem, we have built a three-branch natural gas supply system in the Amesim software and established a gas turbine model in the Simulink software according to its mechanism. In addition, the gas turbine model and the natural gas system model are jointly simulated through the interface. Finally, in accordance with the traditional PID gas turbine controller, an active disturbance rejection controller (ADRC) is designed, which is combined with a bumpless transfer controller including differentiator and integrator to suppress the interference caused by fuel switching. The effectiveness and superiority of this strategy are verified by the complete joint simulations.

Bumpless Transfer H∞ Anti-Disturbance Control of Switching Markovian LPV Systems Under the Hybrid Switching.

This article focuses on the bumpless transfer H∞ anti-disturbance control problem for switching Markovian LPV systems under a hybrid switching law. A parameter-dependent multiple piecewise disturbance observer-based bumpless transfer control strategy is put forward to reject multiple disturbances and reduce switching bumps. First, a hybrid switching law making full use of determinacy and randomness is proposed to improve the bumpless transfer anti-disturbance level by introducing a fixed dwell time in random switching. Second, a generalized bumpless transfer anti-disturbance specification is given to describe the switching quality at the switching points of switching Markovian LPV systems. Third, a solvability condition is established for the bumpless transfer H∞ anti-disturbance control problem, and a parameter-dependent multiple piecewise disturbance observer-based bumpless transfer controller is designed. Finally, an application example has been supplied to demonstrate the availability of the developed method.

Output consensus for switched multi-agent systems with bumpless transfer control and event-triggered communication

This paper considers output consensus for a class of switched multi-agent systems with bumpless transfer control and event-triggered communication. For switched multi-agent systems, all the subsystems of each agent are allowed to be instabilizabled. For the bumpless transfer performance, we suppress control bumps at switching instants, and completely exclude control bumps at triggering instants by constructing a dynamic compensator. Besides, by designing an event-triggered rule, the communication cost is reduced and the positive lower bound between the consecutive triggering instants is guaranteed. Under the co-design of the switching law, bumpless transfer control and event-triggered rule, sufficient conditions guaranteeing output consensus are presented. The effectiveness of the result is validated by an example.

Bumpless transfer control for switched linear systems with exponential stability: a dwell time guaranteed method

In this study, the authors deal with the issue of exponential stability for a class of switched linear systems via bumpless transfer control and pre-assigned dwell time constrained switching. A sufficient condition is given to guarantee both exponential stability and bumpless transfer performance by dual design of a switching law and controllers for the switched linear systems. The sufficient condition requires neither exponential stability nor the bumpless transfer performance for each subsystem. The switching law, which perfectly matched the pre-given dwell time constraints, is of the state-dependent form. By applying a computational procedure, the authors proposed an example of controlling a turbofan engine model is given to illustrate that the aforementioned control design strategy is effective.

Active Fault-Tolerant Control for Electro-Hydraulic Systems With an Independent Metering Valve Against Valve Faults

Aiming at the tough requirements for safety and maintainability in mobile hydraulic systems, in this article, an active fault-tolerant control (FTC) system is proposed against the valve faults of an independent metering valve. Not only moderate faults of activated valves, but also significant faults and unactivated valve faults are considered. Without additional hardware redundancy, analytical redundancy is derived by the coordinate control of other fault-free valves. Accordingly, an FTC system in parallel with a normal controller is designed based on the pressure feedback. It consists of a set of reconfigurable controllers and a decision mechanism. The control signals, control loops, and operating modes can all be precisely reconfigured to adaptively match unmodeled fault dynamics. A bumpless transfer controller based on a latent tracking loop is designed to smooth the switching between the normal controller and FTC. Consequently, random valve faults can be tolerated with minor degradations in motion tracking and energy-saving performance. The feasibility of the FTC system is evaluated by a 2-ton excavator.

H∞ output tracking bumpless transfer control for switched linear systems

AbstractThis study concentrates on the problem of $H_\infty $ output tracking bumpless transfer control for a category of switched linear systems (SLSs). The $H_\infty $ output tracking bumpless transfer control problem is to ensure the SLSs to satisfy the bumpless transfer performance and the $H_\infty $ output tracking properties by co-design of a switching rule and a series of controllers. Firstly, a concept of the bumpless transfer performance for a system in this class is presented. Then, via a Lyapunov function scheme, criteria guaranteeing the bumpless transfer performance and the $H_\infty $ output tracking properties are established. The criteria allow the problem of the $H_\infty $ output tracking bumpless transfer control for subsystems is unsolvable. Finally, an example of controlling a turbofan model is offered for the verification on the effectiveness of the presented control strategy.

A Bumpless Transfer Control Strategy for Switched Systems and Its Application to an Aero-Engine

This article investigates a bumpless transfer control problem for switched systems. Since the control input signal of a controller switching system jumps when a switching occurs, the transient performance of the practical system may suffer bad effects. To avoid the damage to the system caused by the jump of control input signal, we propose a simple bumpless transfer control structure containing a differentiator and an integrator to smooth the control input signal and a common compensator designed to compensate the deviation from the original switching control input signal for eliminating the steady-state error. Furthermore, we give the sufficient conditions to guarantee asymptotic stability for linear and nonlinear bumpless transfer control systems, respectively. Moreover, we verify the recoverability and effectiveness of the proposed control strategy. Finally, a hardware-in-the-loop simulation for a variable cycle engine shows the feasibility and superiority of the proposed method.

Anti-Disturbance Bumpless Transfer Control for Switched Systems With its Application to Switched Circuit Model

A control scheme is developed to estimate and then restrain the unavailable disturbance input of switched systems (SSs), while ruling out the large and sudden jumps in the control input. The suppression on the unavailable disturbance and that on the oscillations in the control input are measured by $H_{\infty }$ anti-disturbance (AD) property and bumpless transfer (BT) property, respectively. Through construction of a switching rule, a disturbance observer together with a controller, a sufficient condition is obtained to ensure the $H_{\infty }$ AD property and the BT performance. At last, a verification of the developed control scheme is offered by adjusting the power voltage of a switched RLC circuit model.

Finite‐time H∞ bumpless transfer control for switched systems: A state‐dependent switching approach

SummaryThis paper addresses the finite‐time H∞ bumpless transfer control problem for switched systems. The main idea lies in designing a state‐feedback controller with amplitude limitation and a state‐dependent switching law to reduce control bumps caused by switching. First, a local bumpless transfer condition is proposed to limit the amplitude of switching controllers at switching points. Second, by introducing a state‐dependent switching law, a prescribed finite‐time H∞ bumpless transfer control performance is attained even if it does not hold for each subsystem or system state remaining on a switching surface. Third, a sufficient condition verifying the solvability of finite‐time H∞ bumpless transfer control problem is established by resorting to multiple Lyapunov function method. Finally, the effectiveness of developed method is illustrated by a numerical example.

Event-triggered bumpless transfer control for switched systems with its application to switched RLC circuits

This article concentrates on the event-triggered bumpless transfer control problem for switched linear systems. The goal is to reduce the control bumps induced by switchings and triggering, and to ensure the stability of the system. First, a novel description of the bumpless transfer performance is presented, quantifying the suppression level on the control bumps in both relative and absolute viewpoints. Then, an improved switching mechanism, an event-triggered scheme and a collection of event-driven controllers are jointly designed. Further, under the designed switching logic, event-triggered rule and controllers, a criterion is established to attain the goal. Besides, Zeno behavior is excluded. Finally, an application on a switched RLC circuit is offered, verifying the efficiency of the developed event-triggered bumpless transfer control strategy.