Passivity-based Adaptive Control Research Articles

Passivity-based adaptive current control loop of cascaded H-bridge multilevel converter for grid-tied photovoltaic system

This paper proposes an algorithm to passivity-based control (PBC) for the current control loop of the cascaded H-bridge converter (CHB) connecting the grid-connected PV system with the space vector modulation (SVM) algorithm using the law of expanding any number of voltage levels. The algorithm SVM in this paper is suitable for CHB converters. It can create a number of high levels of alternating voltage that other methods cannot do. Passivity-based control (PBC) algorithm aims to create a flexible controller that can change its structure or parameters to adapt to changes in the system, ensuring stable system quality, reducing switching losses and gaining energy conversion efficiency. It enhances the capability of accurately delivering power on demand to the grid with the CHB inverter in situations in which the grid demands the mobilization of maximum power from the photovoltaics (PV) system. The simulation results of the 9-level CHB system performed by MATLAB/Simulink software have proved the feasibility of the proposed algorithm.

Taylor series and adaptive passivity-based control for conical tanks level regulation

Taylor series and adaptive passivity-based control for conical tanks level regulation

Passivity-based fractionated payload 6-DOF maneuver control using electromagnetic actuation

Employing fractionated spacecraft architecture with electromagnetic actuation into space missions can enhance resilience and flexibility since all subsystems of conventional monolithic spacecraft are separated as several modules to be easily replaced on-orbit when failure happens. Previous electromagnetic configuration used in fractionated spacecraft would render unexpected forces and torques which may undermine the stability of entire system. This paper considers the maneuver of a separated payload in a fractionated spacecraft architecture (FSA) using electromagnetic actuation with adaptive passivity-based control. The FSA consists of a fractionated payload module (FPM) and a supporting spacecraft module (SSM). Relative motion dynamics of FPM and SSM are formulated on SE(3). An adaptive passivity-based 6-DOF motion control scheme is established for FPM's translation and rotation tracking control simultaneously. The closed-loop equilibrium can be attained by the proposed passivity-based 6-DOF control scheme. The controller has no requirement for the precise inertia knowledge of FPM, which processes the robustness of the modelling errors. Numerical simulations are presented to show the effectiveness of the proposed control scheme.

Payload trajectory tracking of a 5-DOF tower crane with a varying-length hoist cable: A passivity-based adaptive control approach

Payload trajectory tracking of a 5-DOF tower crane with a varying-length hoist cable: A passivity-based adaptive control approach

Passivity-Based Adaptive Fuzzy Control for Stochastic Nonlinear Switched Systems via T–S Fuzzy Modeling

In this paper, state-estimator-based adaptive control is under consideration for a sort of nonlinear stochastic switched systems by Takagi-Sugeno (T-S) fuzzy modeling and sliding mode technique. A new fuzzy sliding surface is established by a reformed state estimator, and a novel adaptive fuzzy reaching motion controller synthesis is carried out to force the state trajectories onto the designated sliding surface in limited moments. A new mean-square exponential stability of the resultant plant with passivity is ensured under the average dwell time method and stochastic stability theory. The key challenge overcome here is that one conditional assumption involved in the previous sliding mode control-based strategies for the considered systems is no longer required despite the unavailable states, unknown perturbations and specified switching signal. At last, a practical data communication network model (DCNM) with simulation is offered to verify the feasibility of the theoretical result.

Passivity-based adaptive robust super-twisting nonlinear control for electro-hydraulic system with uncertainties and disturbances

In this paper, a passive-based adaptive robust super-twisting nonlinear controller (PBARSNC) is proposed for high accuracy torque tracking control of the novel electro-hydraulic loading system with disturbances and uncertainties. The construction of the stability of this electro-hydraulic control system is given using passivity theory that results in a passivity-based controller (PBC). Considering parameter uncertainties and constant or slowly varying disturbances, adaptive law is adopted in the passivity-based controller. Furthermore, super-twisting second-order sliding mode control is used to reject modeling uncertainties and matched disturbances. Passivity theory, adaptive method and super-twisting algorithm are synthesized via the recursive design method. The proposed passive-based adaptive robust super-twisting nonlinear control can guarantee the torque tracking performance in the presence of various uncertainties, which is very important for high-accuracy tracking control of hydraulic servo systems. Extensive simulations are carried out to verify the high-accuracy tracking performance of the proposed control strategy.

Virtually Euler–Lagrange form for feedback passivation of a wide range of non-Euler–Lagrange systems: Adaptive passivity-based control of hepatitis B disease

In this article, a novel technique of feedback passivation is developed for a wide range of non-Euler–Lagrange systems. The reason for this naming “Virtually Euler-Lagrange” is that it is adopted from the error dynamics of Euler–Lagrange systems. An adaptive passivity-based control strategy is proposed in virtually Euler–Lagrange form to treat hepatitis B virus infection. There are several remarkable differences between classic form of passivation and the proposed method, for example, specific and predefined template of storage function in virtually Euler–Lagrange form, which has positive definite auto-extracted form. So, it will be appropriate and time-saving for designing passivity-based control. On the contrary, the process of passivation and control design in conventional formulation is based on time-invariant input-affine systems; however, in virtually Euler–Lagrange form, the system can belong to a wider category. In this regard, two theorems have been proposed to expand the scope of passivity-based control design. Some control design conditions will be released as a result of using this new method. Furthermore, for the first time, passivity-based control has been implemented in the biological area. Control profile design, simulation results, and sensitivity analysis are carried out to evaluate capability of this control approach. Some main biological limitations are also considered, which make the proposed control more realistic.

Passivity-Based Control for Interleaved Double Dual Boost Converters in DC Microgrids Supplying Constant Power Loads

The interleaved double dual boost converter (IDDBC) is considered a promising and reliable approach to interface the low-voltage renewable energy sources (RESs), such as battery packs, fuel cells and photovoltaic (PV) panels, to the DC bus of the DC microgrids. It could give a higher voltage step-up ratio and reduce voltage and current stresses on the power devices. However, the connection of various tightly regulated power converters, which are known as constant power loads (CPLs), would cause negative incremental impedance. Meanwhile, the unmodeled dynamics and load perturbation disturbances are unavoidable in the DC microgrid. These issues would deteriorate the system stability and even lead to system failure. To address these problems, this paper proposes an adaptive passivity-based control (PBC) to handle the DC bus’s large-scale stability issues of the N-phase IDDBC feeding CPL system. A reduced and practical N-phase IDDBC model supplying CPL considering unmodeled dynamics and load perturbation disturbances is proposed to facilitate the controller design. Besides, a nonlinear disturbance observer (NDO) is incorporated with the proposed PBC to improve the robustness against parameter uncertainties and external disturbances. And the global stability of the closed-loop system is proved through the Lyapunov theorem. Finally, simulation and experimental results are demonstrated to verify the feasibility and effectiveness of the proposed controller.

Adaptive Passivity-Based Control of a DC–DC Boost Power Converter Supplying Constant Power and Constant Voltage Loads

This article presents a robust passivity-based control (PBC) strategy to mitigate the instability effect of the dc–dc boost power converter supplying a constant power load and a constant voltage load in dc microgrid systems. The control robustness of the PBC against both line and load variation is significantly improved by adding the nonlinear disturbance observer (NDO). Using the disturbance estimation technique, this observer works in parallel with the PBC strategy to compensate the disturbances of the system through a feed-forward compensation channel. Based on the dissipation property, the PBC strategy ensures the system stability, whereas the NDO guarantees global trajectory tracking to the reference voltage during disturbances. This control strategy not only ensures large-signal stability of the system, but also provides a fastest recovery performance during disturbances of the system as compared with other PBC strategies. The hardware-in-loop and real-hardware experimental results are provided to verify the control robustness of the proposed control strategy.

Adaptive passivity-based control of an autonomous underwater vehicle

An Autonomous Underwater Vehicle (AUV) is a nonlinear nonholonomic dynamical system. Tracking control of AUVs in the presence of disturbances and uncertainties is a challenging problem. In this paper, an adaptive passivity-based algorithm is proposed for tracking control of an AUV. Also, a disturbance estimator has been used to attenuate the effects of unknown disturbances. A proper adaptive rule is designed to estimate unknown parameters and disturbances. The stability of the proposed method is analyzed using passivity properties and the Lyapunov theory. Obtained comparative results show the advantages of the proposed Adaptive Computed Torque Method ACTM plus disturbance estimator.

Featured Cover

The cover image is based on the Research Article Passivity-based adaptive fault-tolerant control for continuous-time Markov jump PWA systems with actuator faults by Nuo Xu et al., https://doi.org/10.1002/rnc.5947.

Adaptive Passivity-Based Multi-Task Tracking Control for Robotic Manipulators

Adaptive control of robot manipulators based on the use of a sliding variable and the passivity property of the dynamic equations was originally designed and successfully applied to task tracking in joint space few decades ago. Surprisingly, no extension is available to date for the multi-task case such that the controller tends towards enforcing strict task priorities as the parameters tend to their real values. Given the importance of both multi-task control and adaptive algorithms, an approach that deals with this situation has an important impact in the robotic field. This letter provides a solution to this problem leveraging on our recent formulation of hierarchical multi-task impedance control for trajectory tracking and on geometric methods for model identification. Experiments are used to validate the stability analysis.

Passivity-based adaptive tracking control of spacecraft line-of-sight relative motion with thrust saturation

This paper considers the control problem of spacecraft line-of-sight (LOS) relative motion with thrust saturation in the presence of unmodeled dynamics, external disturbance and unknown mass property. By using skew-symmetric property, reference trajectory generator and anti-windup technique, a novel passivity-based adaptive sliding mode control (SMC) scheme is proposed without prior knowledge of uncertainty/disturbance bound. Within the Lyapunov framework, the establishment of a real sliding mode (which induces the practical stability of closed-loop error system) is validated. The main contributions are that a new control gain adaptive algorithm is adopted to attenuate the overestimation of switching gain and a differentiable projection-based parameter adaptive algorithm is proposed to force the mass approximator to remain in a desired domain, then the adaptive control law is modified by the reference trajectory generator and anti-windup technique to compensate for the effect of thrust saturation. Finally, simulations are conducted to show the fine performance of proposed control scheme.

Design of a finite time passivity based adaptive sliding mode control implementing on a spacecraft attitude dynamic simulator

Design of a passivity-based adaptive robust control for attitude tracking of a three-axis satellite is investigated in this paper. By defining a virtual angular velocity for the satellite Kinematics and utilizing the finite time passivity features, it is proved that the developed method drives the system trajectories into the equilibrium point for various signs of the satellite quaternions. Therefore, the closer equilibrium point is always selected and the unwinding problem is resolved. A novel structure is defined for the sliding manifold that uses the selected virtual velocity. Then, a dynamic feedback controller is developed that considers uncertain parameters and faulty actuators (unknown inputs). The upper bounds of unknown inputs and unknown inertia moments are estimated by the developed adaptation mechanisms. A three degrees of freedom dumbbell style dynamic simulator has been developed to provide a rigorous evaluation of the suggested algorithms in a dynamic condition near to space. The proposed algorithms have been implemented for both reaction wheels and thrusters as actuators and the effectiveness of the introduced control methodologies was proved.

Passivity-based adaptive trajectory control of an underactuated 3-DOF overhead crane

This paper presents a robust passivity-based adaptive control method for payload trajectory tracking of a three degree-of-freedom overhead crane with a varying-length rigid hoist cable. A reformulation of the overhead crane’s equations of motion is used and an adaptive control law is developed to ensure the system has an output strictly passive (OSP) input–output mapping. The Passivity Theorem is used to prove that the closed-loop system is input–output stable when an OSP negative feedback controller is implemented. Convergence and boundedness of the payload trajectory tracking error is proven with two candidate OSP feedback controllers, including a constant gain and a strictly positive real (SPR) controller. Numerical simulations and experiments are performed with the proposed control method and two state-of-the-art control laws from the literature. The results demonstrate the practicality of the proposed control method and the improved performance of the proposed SPR controller in the experiments compared to the controllers from the literature.

Adaptive passivity-based control extended for unknown control direction

This research extends the design of adaptive passivity-based controllers (APBC), proposing a normalized APBC (NAPBC) for nonlinear dynamical systems with a direction of control unknown. The plant also has an accessible single-input and a single-output, smooth behavior, linear explicit parametric dependence, and unknown parameters. The proposed method can handle unknown control direction through an alternate and more straightforward method than Nussbaum gains, having two fewer parameters. We present the stability proof of the controlled system. Besides, the proposed NAPBC expands the tuning method for normalized fixed gains or time-varying gains, reducing the trial and error procedure. Finally, we apply the proposed methodology step by step to a conical tank-scale pilot plant. Comparative experimental results show the proposed NAPBC has better indexes ISI, Ess, MO, IAE, and Ts.

Dynamic Modeling and Adaptive Control of a Single Degree-of-Freedom Flexible Cable-Driven Parallel Robot

This paper investigates the dynamic modeling and adaptive control of a single degree-of-freedom flexible cable-driven parallel robot (CDPR). A Rayleigh–Ritz cable model is developed that takes into account the changes in cable mass and stiffness due to its winding and unwinding around the actuating winch, with the changes distributed throughout the cables. The model uses a set of state-dependent basis functions for discretizing cables of varying length. A novel energy-based model simplification is proposed to further facilitate reduction in the computational load when performing numerical simulations involving the Rayleigh–Ritz model. For control purposes, the massive payload assumption is used to decouple the rigid and elastic dynamics of the system, and a modified input torque and modified output payload rate are used to develop a passive input–output map for the naturally noncollocated system. A passivity-based adaptive control law is derived to dynamically adapt to changes in cable properties and payload inertia, and different forms of the adaptive control law regressor are proposed. It is shown through numerical simulations that the adaptive controller is robust to changes in payload mass and cable properties, and the selection of the regressor form has a significant impact on the performance of the controller.

Passivity-Based Bilateral Tele-Driving System With Parametric Uncertainty and Communication Delays

In this letter, a new bilateral tele-driving control design is proposed to enable a human driver to tele-drive a car-like mobile robot with haptic feedback. In the presence of communication delays and dynamic parametric uncertainties, a passivity-based adaptive control algorithm is designed to achieve scaled coordination between a local and a remote robot. The efficacy of the proposed control scheme is verified through numerical simulations.

Adaptive control design with S-variable LMI approach for robustness and L2 performance

ABSTRACTMatrix inequality-based results are proposed for the design of direct adaptive control. The focus is on guaranteeing robustness of the closed-loop when facing both structured parametric uncertainties and input disturbances. Results apply to systems in descriptor form with polytopic uncertainties and readily extend to systems rational in the uncertain parameters. The exposed methodology is an extension of previous studies started in cooperation with Alexander L. Fradkov. These studies aim at applying up-to-date linear robust control tools for passivity-based adaptive control. The paper contributes to this framework with new parameter-dependent Lyapunov functions and new degrees of freedom in the adaptive laws offering the possibility to design controllers with improved closed-loop performances.

Passivity-Based Control of Switched Reluctance-Based Wind System Supplying Constant Power Load

This paper presents a passivity-based control (PBC) scheme for the switched reluctance generator (SRG) in small-scale wind energy conversion systems for dc microgrid applications. The main objective is to stabilize the output voltage in case the system supplies constant power loads (CPLs) and operates with maximum power point tracking (MPPT). Stability improvement and dc-link ripple reduction in the presence of CPLs is achieved using system-level modeling of SRG-based dc microgrid through the Euler-Lagrange system (ELS) from the viewpoint of the machine physical structure. Compared with other control methods, the proposed MPPT method based on passivity-based speed controller employs the back electromotive force (EMF) in the generation process as a position-dependent voltage source to overcome the major challenge of SRG complicated uncertain dynamic model. To deal with the time-varying inductance and back EMF of SRG, an adaptation mechanism is incorporated in the proposed adaptive PBC and the control design is constructed by using the Lyapunov theorem where the closed-loop stability is ensured. The effectiveness of the proposed method in avoiding instability effects of SRG and CPL with voltage ripple reduction and precise wind turbine speed tracking is investigated with simulation results and validated with experimental by using a four-phase, 8/6 SRG drive system.