Passivity-based Control Scheme Research Articles

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.

Harmonics Suppression and Stability Improvement for Power Router in Nonideal Grid Conditions: A Multi-Port Passivity-Based Collaborative Control Scheme

Harmonics Suppression and Stability Improvement for Power Router in Nonideal Grid Conditions: A Multi-Port Passivity-Based Collaborative Control Scheme

The Hybrid Passivity-Based Control Strategy of a Novel Unidirectional Five-Level Rectifier Under the Unbalanced Load

The Hybrid Passivity-Based Control Strategy of a Novel Unidirectional Five-Level Rectifier Under the Unbalanced Load

Hybrid passivity‐based control of a three single‐phase star‐connected unidirectional five‐level rectifier with a space vector pulse‐width modulation algorithm for voltage balance

SummaryThe unidirectional multilevel rectifier has been used in numerous industrial applications due to its reduced active power switches, higher power density, and lower cost compared to conventional bidirectional converters. Recently, the unidirectional five‐level rectifier has been proposed for its lower device stress and the potential for extension to higher levels. However, it adopts a conventional linear proportional integral (PI) control strategy and sinusoidal pulse‐width modulation (SPWM) method, resulting in a complex control structure, particularly for the balance control of the midpoint voltage, and suboptimal dynamic performance. To address this issue and enhance system's large‐scale stability, a hybrid passivity‐based control (PBC) strategy, along with a simplified mathematical model, has been proposed. The hybrid PBC control strategy includes an outer loop active disturbance rejection (ADR)‐PI controller and inner loop PBC controller, providing a simple overall control structure and strong anti‐interference ability. Additionally, a space vector pulse‐width modulation (SVPWM) algorithm has been briefly introduced and applied to further improve the recovery and balance speed of the DC‐side capacitor voltages. Simulation and experiment results have validated the feasibility and effectiveness of the proposed hybrid PBC strategy and the SVPWM algorithm.

Passivity-based control strategy for resonant converter based on Euler–Lagrange model

The LLC resonant converter is a widely used DC/DC converter that offers the benefit of enabling soft switching compared to classical DC/DC converters. However, traditional PI control strategy based on a linear model has drawbacks such as slow dynamic response and poor anti-interference performance. To overcome the shortage, a passivitybased control strategy based on the Euler–Lagrange (EL) model is proposed in this paper to improve the dynamic performance of the half-bridge LLC resonant converter. In addition, the stability of the system based on the proposed strategy is analyzed and verified. Further, the effectiveness and performance of the proposed strategy is verified in the simulation by comparing with the traditional PI controller. Finally, a prototype was built to verify the dynamic performance of the LLC resonant converter based on the proposed control strategy.

Distributed Coordinated Control for Stabilization of Multi-Inverter Power Plant

For a power plant integrated with multiple parallel inverters, the impedance variation of the power grid and the natural plug-and-play property of the inverters bring stability challenges. One of the issues is nonlinear wideband oscillations of the grid current and voltage. This paper proposes a distributed coordinated control for the stabilization of the multi-inverter power plant. The passivity-based control (PBC) scheme designs the controller of a single grid-connected inverter from the perspective of energy reshaping, which ensures the stability of the entire system when it is extended to multiple inverters in parallel. A nonlinear observer is proposed to discover the changeable frequency drifting of wideband oscillations so that the PBC scheme can adapt to nonlinear disturbances, such as inverter plug-and-play and fluctuated grid impedance. Moreover, to achieve mutual coordination and distributed control of damping characteristics among multi-inverters to ensure the good dynamic performance of the system, an adaptive dynamic coordination loop based on grid impedance identification is incorporated in the PBC scheme. The Lyapunov stability of the system with the proposed PBC controller is proven in the paper. The effectiveness of the proposed scheme is verified by simulation and experimental results.

An Adaptive Controller Based on Interconnection and Damping Assignment Passivity-Based Control for Underactuated Mechanical Systems: Application to the Ball and Beam System

In this paper, an adaptive technology and the interconnection and damping assignment passivity-based control method are combined to solve the stabilization problem for underactuated mechanical systems with uncertainties (including matched and unmatched). These uncertainties include unknown friction coefficients and unknown terms in kinetic energy and potential energy. A novel adaptive interconnection and damping assignment passivity-based control scheme is proposed and an adaptive stabilization controller is designed to make the closed-loop system locally stable. Verification is conducted on the ball and beam system. The locally asymptotic stability is demonstrated using the LaSalle’s invariance principle and approximate linearization. The effectiveness of the proposed control law is verified through numerical simulations.

A Passivity-based direct power control scheme of a back to back NPC converter

In this paper, a direct power control (DPC) is proposed in order to improve the power dispatch in electrical power grids, as well as in microgrids. The objective of defining the active power and reactive power as state variables is to get a representation of the first level in a hierarchical control. The DPC model is studied under passivity rules, and an implementation of passivity-based control is proposed. Simulations are carried out to show the effectiveness of the proposed research.

Cooperative Passivity-Based Control of Nonlinear Mechanical Systems

In this work, we propose two cooperative passivity-based control methods for networks of mechanical systems. By cooperatively synchronizing the end-effector coordinates of the individual agents, we achieve cooperation between systems of different types. The underlying passivity property of our control approaches ensures that cooperation is stable and robust. Neither of the two approaches rely on the modeling information of neighbors, locally, which simplifies the interconnection of applicable systems and makes the approaches modular in their use. Our first approach is a generalized cooperative Interconnection-and-Damping Assignment passivity-based control (IDA-PBC) scheme for networks of fully actuated and underactuated systems. Our approach leverages the definition of end-effector coordinates in existing single-agent IDA-PBC solutions for underactuated systems to satisfy the matching conditions, independently of the cooperative control input. Accordingly, our approach integrates a large set of existing single-agent solutions and facilitates cooperative control between these and fully actuated systems. Our second approach proposes agent outputs composed of their end-effector coordinates and velocities to guarantee cooperative stability for networks of fully actuated systems in the presence of communication delays. We validate both approaches in simulation and experiments.

Research on a DC–DC Converter and Its Advanced Control Strategy Applied to the Integrated Energy System of Marine Breeding Platforms

The deep-sea aquaculture industry will become one of the important pillars of the future marine economy. However, the application of clean energy in the new scenario needs to be strengthened for platform operation. For this kind of renewable-energy distributed-generation system, an energy storage system is essential. A bidirectional DC–DC converter is essential for distributed power generation systems. It connects a variety of renewable energy sources with energy storage cells. A high-gain bidirectional Cuk circuit with zero ripple is proposed in the paper. It is characterized by a simple structure, zero ripple, low voltage stress of semiconductor power devices, and high voltage gain. A passivity-based control with linear active disturbance rejection is proposed to solve the problems of the large steady-state error. The zero steady-state error, strong robustness, and whole-range stability have been obtained for the proposed control strategy. Finally, a simulation was carried out. A 100 W, 48 V/400 V prototype was built to verify the validity of the theoretical analysis for the proposed circuit. The improved passivity-based control strategy was verified to solve the contradiction between rapidity and overshoot. It can be realized to improve the dynamic performance of the proposed converter and achieve robust control.

Passive Backstepping Control of Dual Active Bridge Converter in Modular Three-Port DC Converter

A dual active bridge (DAB) converter in a modular three-port DC converter is the key equipment to connect distributed energy and energy storage units and realize its efficient and large-scale utilization. When a DAB converter with traditional control is disturbed by the input voltage of distributed energy sources, some problems occur, such as large fluctuation of load voltage and slow dynamic response. In order to address such problems, this paper firstly starts with the single-phase shift control of the DAB converter, establishes the dynamic mathematical model of the DAB converter according to the nonlinear characteristics of the converter, transforms it into the passive form of Euler–Lagrange (E-L) model and designs the passive controller based on the analysis of the passive nature and stability of the converter, in order to improve the energy dissipation rate and ensure the global stability of the system. Secondly, in conjunction with the backstepping control, a passive backstepping controller is designed with the goal of shifting the comparison to eliminate errors caused by input disturbances and achieve fast-tracking of the reference voltage. Finally, a DAB simulation model based on passive backstepping control is established in Matlab/Simulink. By selecting the appropriate injection damping value, it is compared with traditional PI control and passivity-based control strategy, and the effectiveness of forward and reverse power transmission modes of the DAB converter under passive backstepping control is verified. The results show that the DAB converter with passive backstepping control has better dynamic performance and stronger robustness after sudden changes in input voltage.

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 Output Voltage Regulation in a Fuel Cell/Boost Converter System.

In this paper, a passivity-based control (PBC) scheme for output voltage regulation in a fuel-cell/boost converter system is designed and validated through real-time numerical results. The proposed control scheme is designed as a current-mode control (CMC) scheme with an outer loop (voltage) for voltage regulation and an inner loop (current) for current reference tracking. The inner loop's design considers the Euler-Lagrange (E-L) formulation to implement a standard PBC and the outer loop is implemented through a standard PI controller. Furthermore, an adaptive law based on immersion and invariance (I&I) theory is designed to enhance the closed-loop system behavior through asymptotic approximation of uncertain parameters such as load and inductor parasitic resistance. The closed-loop system is tested under two scenarios using real-time simulations, where precision and robustness are shown with respect to variations in the fuel cell voltage, load, and output voltage reference.

Passivity-based control strategy for hexagonal converter under unbalanced power grid

Passivity-based control strategy for hexagonal converter under unbalanced power grid

A Passivity-Based Velocity Control Method of Hardware-in-the-Loop Simulation for Space Robotic Operations

The hardware-in-the-loop (HIL) simulation is an important approach to test space robotic operations, rendering virtual free-floating dynamics on robotic facilities. However, this approach suffers from velocity divergence due to intrinsic time delay in the control loop. This paper proposes a passivity-based control strategy to handle the simulation divergence. A HIL simulation system with an industrial robot is modelled and its divergence problems are analyzed through numerical simulations. Then, through representing the HIL simulation system in a passivity network of view, the passivity observer (PO) of the dynamic system is established. The PO includes the effect of a real contact damping on energy flow of the passivity network during a contact process. Thus, a passivity controller is defined. Moreover, a real-time estimation method for contact damping is presented. Finally, collision experiments against a virtual wall and real collision experiments are both implemented. The experimental results show that the simulation divergence due to the time delay can be prevented by the proposed control strategy, and that the velocity characteristics with high fidelity are rendered on the HIL simulation system.

Impedance Control on Arbitrary Surfaces for Ultrasound Scanning Using Discrete Differential Geometry

We propose an approach to robotic ultrasound scanning and interaction control with arbitrary surfaces using a passivity-based impedance control scheme. First, we introduce task coordinates depending on the geometry of the surface, which enable hands-on guidance of the robot along the surface, as well as teleoperated and autonomous ultrasound image acquisition. Our coordinates allow controlling the signed distance of the robot to the surface and alignment of the tool to the surface normal using classical impedance control. This corresponds to implicitly obtaining a foliation of parallel surfaces. By setting the desired signed distance negative, i.e., into the surface, we obtain passive contact forces and simultaneously provide an intuitive way to control the maximum penetration depth into the surface. We extend the approach to also incorporate coordinates allowing to control the specific point on the surface and, automatically, on all parallel surfaces. Finally, we demonstrate the performance of the controller on the seven degrees of freedom lightweight robot DLR <sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">Miro</small> : the robot tracks complex trajectories while accurately keeping the desired distance to the surface and applying an almost constant contact force. Finally, we compare the approach to the state of the art.

Interval-Arithmetic-Based Robust Control of Fully Actuated Mechanical Systems

We propose a control approach for fully actuated mechanical systems using interval arithmetic, which guarantees global uniform ultimate boundedness of the tracking error and robust performance despite model uncertainties and input disturbances. Existing robust control methods often require computationally expensive or empirical estimations of bounds of state-dependent, nonlinear perturbations, arising from model mismatches. Our robust feedback control approach is different and removes these difficulties by using interval arithmetic to determine online the worst case perturbation acting on the error dynamics. We present two interval-arithmetic-based robust controllers by robustifying inverse-dynamics and passivity-based nominal control schemes. The effectiveness of our approach is demonstrated on a real robot manipulator with uncertain dynamics.

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&#x2013;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.

Special Section on Mechanics of Electrochemical Energy Storage and Conversion

The increasing population growth, depletion of natural resources, and rising energy demand have sparked enormous research endeavors in electrochemical energy storage and conversion. For example, rechargeable lithium-ion batteries are ubiquitous in everyday life. Mechanics plays a critical role in designing a wide range of energy technologies. The emerging field of electro-chemo-mechanics, the interplay of mechanics and electrochemistry, is crucial for understanding the coupled physiochemical processes. The electrochemical phenomena can govern the mechanical response such as stress generation, deformation, fracture initiation/propagation, elasticity, and plasticity. Similarly, mechanical phenomena also influence the electrochemical properties such as device reliability and durability. Therefore, the in-depth mechanical study of electrochemical systems is urgently necessary for fundamental science and technological applications. Over the past few years, there has been significant progress in modeling, theories, and experimental characterizations of mechanical aspects of energy storage and conversion. This timely special issue addressed some recent advances in electro-chemo-mechanics. We have selected eight papers covering a wide range of issues in batteries and fuel cells such as (i) deformation, microstructural changes, creep, overcharge detection and prevention, optimization of structural parameters in batteries and (ii) temperature and load variations, metal-free cathode catalyst in fuel cells. The selected papers cover a gamut of electrochemical-mechanics centric research in energy storage and conversion.In this issue, Adams et al. used ex-situ X-ray microtomography to study cycling-induced microstructural changes in alloy anodes for Lithium-ion Batteries. They showed that besides mechanical degradation of electrodes, excessive volume expansion could also influence transport networks in the active materials and supporting phases of the electrode. Dienemann et al. measured the time- and temperature-dependent mechanics of two thicknesses of commercial lithium anodes inside a dry industrial room, where battery cells are manufactured at high volume. Furthermore, they examined the anisotropic microstructure of lithium anodes and its effect on bulk creep mechanics. Zaidi et al. proposed a robust passivity-based control scheme for 1.26 KW proton exchange membrane fuel cell under temperature and load variations. Li et al. performed experiments to study overcharge detection and prevention with temperature monitoring of Li-ion batteries. Furthermore, they developed a linear regression-based machine learning model to validate the experimental results. Nguyen et al. experimentally studied the deformation behavior of single prismatic battery cell cases and cell assemblies loaded by internal pressure. They demonstrated that the use of nominal cell casting characteristics significantly underestimates the resistance provided by the cell case to counter swelling of the active battery components. Bao et al. performed combined experiments and computation (computational fluid dynamics and multi-objective optimization method) to study structural parameters of the air-cooled system for the lithium battery pack. Woodcox et al. performed density functional theory (DFT) calculations to investigate 19 CaxSn1−x structures (six bulk materials and 13 alloys) as potential battery anodes. They found that for stable/metastable compositions of CaxSn1−x, those sharing the same chemical composition (stoichiometry) also share remarkably similar material properties, indicating that such materials would be advantageous for uses in battery anodes. Miao et al. developed a two-dimensional, two-phase transport model to investigate the transport characteristics in direct methanol fuel cells (DMFCs) using platinum group metal (PG)-free cathode catalysts. To achieve the projected performance target of 300 mW/cm2 peak power density, catalytic activities of both the anode and cathode catalysts need to be improved by one order of magnitude compared with the state-of-the-art commercial catalysts.We believe that this special issue will be a valuable contribution to the energy storage and conversion literature and open new frontiers for the researchers. The interdisciplinary field of electro-chemo-mechanics is rapidly evolving. Our special issue will motivate many researchers to implement novel techniques such as artificial intelligence, digital twins, and automated advanced manufacturing in this field and initiate new collaborations between experimentalists, theorists, and modelers. We would like to thank all contributors to this special section issue for submitting their latest high-impact work addressing the mechanics aspects of electrochemical energy storage. Also, special thanks would go out to the invited reviewers for helping us further enhance the quality of the articles. A special issue of ASME Applied Mechanics Reviews is also being planned for the second half of 2022 and developed in collaboration with the ASME Journal of Electrochemical Energy Conversion and Storage, dedicated to state-of-the-art reviews that highlight contributions of the discipline of electrochemical energy conversion and storage to research in applied mechanics.

Port-Hamiltonian Modeling and IDA-PBC Control of an IPMC-Actuated Flexible Beam

In this paper, the infinite-dimensional port-Hamiltonian modelling and control problem of a flexible beam actuated using ionic polymer metal composite (IPMC) actuators is investigated. The port-Hamiltonian framework is used to propose an interconnected control model of the mechanical flexible beam and the IPMC actuator. The mechanical flexible dynamic is modelled as a Timoshenko beam, and the electric dynamics of the IPMCs are considered in the model. Furthermore, a passivity-based control-strategy is used to obtain the desired configuration of the proposed interconnected system, and the closed-loop stability is analyzed using the early lumped approach. Lastly, numerical simulations and experimental results are presented to validate the proposed model and the effectiveness of the proposed control law.