Article
Mathematics, Applied
Wenjing Yang, Jianwei Xia, Miao Yu, Na Zhang
Summary: This paper investigates the decentralized adaptive funnel control for a class of uncertain large-scale nonlinear systems. A new adaptive decentralized funnel controller is recursively constructed using a new funnel control method with a barrier Lyapunov function to achieve output tracking of given transient behavior. An auxiliary nonlinear function is introduced to solve the interconnection terms issues in the controller design. Dynamic surface control is applied to the backstepping design to avoid complexity problems in the backstepping procedure. The proposed control scheme ensures bounded signals and tracking error evolution within the funnel. The effectiveness of the scheme is demonstrated through a numerical example and a third-order power network system model.
APPLIED MATHEMATICS AND COMPUTATION
(2023)
Article
Engineering, Electrical & Electronic
Yun Long, Jinhua Du
Summary: An adaptive position control strategy is proposed in this article to improve the position control accuracy of a switched reluctance motor (SRM)-based electromechanical actuator (EMA) system. The strategy includes the design of an adaptive fast terminal sliding mode controller (AFTSMC) to address parameter uncertainty and load disturbance, and a current-limited direct torque controller (CL-DTC) to track the reference torque with lower ripple and prevent overheating. Experimental results demonstrate the effectiveness and superiority of the proposed strategy.
IEEE TRANSACTIONS ON TRANSPORTATION ELECTRIFICATION
(2023)
Article
Automation & Control Systems
Junxiao Wang, Li Yu
Summary: This article proposes an adaptive resonant-equivalent-input-disturbance-observer-based optimized position precision control method for a magnetic levitation system, aiming to improve the rejection of multiple disturbances with unknown frequency resonant disturbance. Considering the strong nonlinear nature of the magnetic levitation system, a model-predictive-control-based optimization solution is designed using Taylor series expansion, but the predictive model accuracy is lacking. To account for model error and multiple disturbances, an adaptive resonant equivalent input disturbance estimator is developed, which can observe the unknown frequency resonant disturbance. Then, a disturbance estimation integrated model-predictive control scheme is constructed for online optimization. Rigorous analysis is also provided. Experimental results demonstrate that the proposed control method improves position precision and disturbance rejection compared to existing disturbance attenuation methods.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Engineering, Mechanical
Yunlang Xu, Chenyang Ding, Xinyi Su, Zhi Li, Xiaofeng Yang
Summary: This paper proposes an enhanced unknown system dynamics estimator (USDE)-based sliding mode control (USDE-SMC) method by a novel predictive-adaptive switching (PAS) controller (USDE-SMC-PAS) to improve the control performance of the reluctance actuator maglev system. By achieving characteristics such as high levitation accuracy, high dynamic response, and reduced chattering, this method significantly improves the control performance.
NONLINEAR DYNAMICS
(2023)
Article
Automation & Control Systems
Huanqing Wang, Liyuan Shao
Summary: This article presents an adaptive quantized funnel control scheme to address the output tracking control problem for a class of uncertain strict-feedback nonlinear systems, ensuring globally uniformly bounded closed-loop signals and output tracking error within prescribed funnel performance bound. Simulation results demonstrate the effectiveness of the proposed control scheme.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2021)
Article
Mathematics, Applied
Xia Song, Lihua Shen, Fuyang Chen
Summary: An adaptive backstepping position tracking control using neural network is proposed for the translational system of quadrotor unmanned aerial vehicle (QUAV). The control method combines intermediary control to handle under-actuation problem and NN approximation strategy to compensate system uncertainty. Compared to traditional methods, the proposed adaptive NN position control effectively alleviates computation burden.
Article
Engineering, Chemical
Gexin Chen, Huilong Liu, Pengshuo Jia, Gengting Qiu, Haohui Yu, Guishan Yan, Chao Ai, Jin Zhang
Summary: A nonlinear adaptive backstepping control method was proposed to address parameter uncertainty in an electro-hydraulic servo closed-loop pump control system, improving control accuracy and robustness. Experimental results confirmed the effectiveness of the control strategy, achieving high precision control with steady-state accuracy of +/- 0.02 mm, laying a solid foundation for the engineering application and promotion of the pump control system.
Article
Acoustics
S. Abhishek, Sanjukta Chakraborty
Summary: In this work, a novel frequency adaptive optimal control algorithm is developed to provide the desired response of the structural system with an ideal control effort for each excitation frequency range. The control gain is designed to have similar frequency response characteristics to the structural system. The proposed control algorithm is verified to be stable and the optimal gain constants are obtained by minimizing the H2 norm of the structural output. Thorough investigation shows that the algorithm influences the appropriate dynamic properties of the system at a specific excitation frequency and this behavior persists in case of perturbations in the structural system.
JOURNAL OF SOUND AND VIBRATION
(2023)
Article
Mathematics, Interdisciplinary Applications
Fengyun Li, Shaohua Luo, Guanci Yang, Hassen M. Ouakad
Summary: This paper investigates an adaptive backstepping funnel control scheme with an event-triggered mechanism for a chaotic dual-mass Micro-Electro-Mechanical Systems (MEMS) gyroscope. The mathematical model of the dual-mass micro-gyroscope is first developed based on a mutual mechanical coupling. Then, its inherent nonlinear characteristics under different spring and coupling coefficients, all of which have noticeable impacts on the system sensitivity, are fully examined through phase and Lyapunov exponent diagrams.
CHAOS SOLITONS & FRACTALS
(2023)
Article
Automation & Control Systems
Lijuan Chen, Jishang Jiang, Wei Gao, Chuan Wang, Wenqiang Xu, Chao Ai, Gexin Chen
Summary: The study focuses on a valve-controlled asymmetric cylinder loading system. To address the issues of low loading accuracy, external interference, and nonlinear and uncertain parameters in position control of electro-hydraulic servo loading systems, a position control strategy using adaptive backsliding control is proposed. The system is divided into subsystems to ensure stability using the Lyapunov stability criterion, and the unknown parameters are expressed by known parameters for stability. Experimental verification is conducted using a hardware-in-a-loop platform, demonstrating the effectiveness of the control method. The results show significant improvements in deviation and phase lag compared to a PID controller, indicating the potential of the proposed adaptive backsliding control method for high performance hydraulic loading systems.
CONTROL ENGINEERING PRACTICE
(2023)
Article
Multidisciplinary Sciences
Hangjun Zhang, Jinhui Fang, Huan Yu, Huibin Hu, Yuzhu Yang
Summary: This paper proposes a disturbance observer-based adaptive position controller for cutterhead anti-torque systems. The proposed method utilizes non-linear adaptive control, disturbance observer method, and sliding mode control, and is validated using a virtual test rig based on MATLAB and AMESim co-simulation. Simulation results demonstrate that the proposed method performs well in tracking tasks in the presence of uncertainties.
Article
Automation & Control Systems
Xuanju Dang, Xiaoan Zhao, Chao Dang, Hui Jiang, Xiru Wu, Lantian Zha
Summary: An incomplete differential-based improved adaptive backstepping integral sliding mode control (ID-BIABISMC) is proposed in this paper to enhance the position control accuracy of hydraulic servo systems by addressing non-structural uncertainties such as nonlinear friction. Experimental results demonstrate that the proposed method outperforms traditional control methods in terms of tracking performance.
Article
Computer Science, Information Systems
Yaguang Li, Yuanchun Jiang, Jianshan Sun, Chunhua Sun, Yezheng Liu, Hai Wang
Summary: This paper presents an adaptive fuzzy output tracking control scheme for a class of strict-feedback systems with an unknown control gain. An ideal controller that achieves finite-time stabilization of the filtered tracking error system is approximated by an ideal fuzzy logic system. The actual fuzzy function is used as the controller to estimate the ideal fuzzy system through online adjustment of system parameters. A tau-observer is designed to handle the unknown fuzzy control error. Unlike previous studies, new parameter adaptive laws are constructed without requiring derivative calculations in the filtered tracking error system. Thus, an adaptive direct fuzzy controller based on a tau-observer is proposed. The practical finite-time stabilization of the output tracking error and the boundedness of all states in the closed-loop system are ensured. Finally, the effectiveness of the control criterion is verified through two simulation examples.
INFORMATION SCIENCES
(2022)
Article
Automation & Control Systems
Liqiang Tang, Yongliang Yang, Xianzhong Chen, Qing Li
Summary: This paper proposes a robust adaptive dynamic surface control (DSC) design approach for switching strict feedback nonlinear systems with multiple switching control gains and unknown control directions. Multiple Nussbaum-type gains are designed to capture the multiple unknown control directions. A common Lyapunov function is constructed for all subsystems using the backstepping technique. The dynamic surface control technique is introduced to decrease computation complexity.
INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL
(2023)
Article
Engineering, Multidisciplinary
Aisha Sir Elkhatem, Seref Naci Engin
Summary: This study proposes a novel method to automatically adjust the weighting matrices in LQR controllers to compensate for model insufficiencies against disturbances. Experimental results demonstrate the effectiveness of this method for both LQR and LQR-PI controllers, achieving stabilization of the quadrotor in the desired position and higher tracking performance.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Energy & Fuels
Max A. Buettner, Niklas Monzen, Christoph M. Hackl
Summary: A novel artificial neural network-based optimal feedforward torque control strategy is proposed for Interior Permanent Magnet Synchronous Machines (IPMSMs) to compute the optimal reference currents. Compared to conventional methods, this strategy is faster, easier to implement, and can consider nonlinear characteristics of the machine, resulting in very accurate reference currents.
Article
Automation & Control Systems
Athina Birda, Christoph Grabher, Christoph M. Hackl, Joerg Reuss
Summary: This article derivates analytical expressions for the dc-link capacitor current and the inverter current for two-level VSIs feeding IPMSMs controlled by SOPWM. The effect of various pulse patterns on the inverter current and dc-link capacitor current ripples are evaluated through experimental results, validating the correctness of the derived expressions.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2022)
Article
Multidisciplinary Sciences
Haotian Xie, Jianming Du, Dongliang Ke, Yingjie He, Fengxiang Wang, Christoph Hackl, Jose Rodriguez, Ralph Kennel
Summary: This article proposes a fast quadratic programming solver for multistep predictive current control. By rearranging the objective function and preselecting vectors close to the reference derivative, the number of searched switching states is significantly reduced, resulting in improved current control quality and computational efficiency.
Article
Green & Sustainable Science & Technology
Mostafa Ahmed, Ibrahim Harbi, Christoph M. Hackl, Ralph Kennel, Jose Rodriguez, Mohamed Abdelrahem
Summary: This paper discusses the MPPT based on finite-set model predictive control (FS-MPC) in photovoltaic (PV) systems. Two algorithms are developed to reduce the number of required sensors without altering the efficiency of FS-MPC. The first algorithm utilizes an accurate model of the PV system to estimate the output capacitor voltage, while the second algorithm utilizes an extended Kalman filter (EKF) to estimate the PV current. The proposed methodologies are compared with the conventional FS-MPC with full sensor utilization, and their robustness against parameter variation is examined. Validation is performed through simulation and experimental tests at different operating conditions.
IET RENEWABLE POWER GENERATION
(2022)
Article
Engineering, Electrical & Electronic
Issa Hammoud, Sebastian Hentzelt, Ke Xu, Thimo Oehlschlagel, Mohamed Abdelrahem, Christoph Hackl, Ralph Kennel
Summary: This article presents a real-time implementation of a continuous-control-set model predictive current controller for two types of permanent magnet synchronous machines. The constrained optimization problem is solved using a slack formulation, and the controller is tested on two different models of machines. The experimental results demonstrate that the controller performs well in electrical drive applications.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2022)
Article
Automation & Control Systems
Julian Kullick, Christoph M. Hackl
Summary: This paper presents a novel and simple approach for modeling, identification, and optimal torque control of induction machines. The approach utilizes a machine model that considers nonlinear flux linkages and iron losses, a machine identification procedure that produces temperature and frequency dependent machine maps, and an offline optimization method for generating optimal current references. Experimental results show that this approach can significantly improve the efficiency of induction machines.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Ibrahim Harbi, Mostafa Ahmed, Christoph M. Hackl, Jose Rodriguez, Ralph Kennel, Mohamed Abdelrahem
Summary: This article proposes a dual-vector finite-control-set model predictive control (FCS-MPC) for a nine-level active neutral point clamped (ANPC) converter. The proposed control scheme reduces computational burden and coordinates multiple objectives effectively. Mathematical analysis and experimental implementation show that the proposed method outperforms other control methods in terms of steady-state errors, THDs, harmonic distribution, and execution times.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2023)
Review
Green & Sustainable Science & Technology
Zhao Song, Christoph M. M. Hackl, Abhinav Anand, Andre Thommessen, Jonas Petzschmann, Omar Kamel, Robert Braunbehrens, Anton Kaifel, Christian Roos, Stefan Hauptmann
Summary: The transition towards a sustainable and renewable-energy centered power system brings about significant challenges and requires a corresponding shift in operation strategies towards more intelligence and digitization. Digital twin systems (DTSs) have been identified as a promising approach for achieving optimal, reliable, and secure operation in power systems. This paper comprehensively reviews the applications of digital twins in power systems and proposes a generic definition of DTSs that can be further extended into a system of digital twin systems (SDTSs), enabling interaction and regulation between different DTSs through a central data and communication interface.
Article
Energy & Fuels
Simon Wiedemann, Christoph Michael Hackl
Summary: The proposed method allows for simultaneous estimation and compensation of nonlinear voltage deviations in voltage source inverters and synchronous machine models, using physically inspired structured artificial neural networks.
IEEE TRANSACTIONS ON ENERGY CONVERSION
(2023)
Article
Automation & Control Systems
Yuebin Pang, Jovan Knezevic, Daniel Glose, Christoph Hackl
Summary: This article investigates the impact of inaccuracies in inductances on the stability of sensorless control schemes for electrically excited synchronous machines in automotive applications. A compensation method is proposed to overcome this problem and ensure global convergence/stability of the observer, which is confirmed by experimental results on an EESM test bench.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Engineering, Electrical & Electronic
Felix Rojas, Cristobal Jerez, Christoph Michael Hackl, Oliver Kalmbach, Javier Pereda, Jonathan Lillo
Summary: MMCCs are a promising power electronics topology for high-power applications, but they are prone to faults due to high levels of thermal, electrical, and mechanical stress and a large number of components, reducing their reliability.
IEEE OPEN JOURNAL OF THE INDUSTRIAL ELECTRONICS SOCIETY
(2022)
Article
Engineering, Electrical & Electronic
Felix Rojas, Cristobal Jerez, Christoph M. Hack, Oliver Kalmbach, Javier Pereda, Jonathan Lillo
Summary: This article comprehensively surveys the fault tolerance, fault detection and diagnosis (FDD), and system reconfiguration strategies of modular multilevel cascade converters (MMCCs). By using cell redundancy-based FDD methods and system reconfiguration techniques, the reliability, availability, and safety of MMCCs can be improved for critical energy applications.
IEEE OPEN JOURNAL OF THE INDUSTRIAL ELECTRONICS SOCIETY
(2022)
Article
Engineering, Electrical & Electronic
Shih-Wei Su, Hannes Boerngen, Christoph M. Hackl, Ralph Kennel
Summary: This article proposes a nonlinear current control system for reluctance synchronous machines (RSMs) using analytical flux linkage prototype functions. By adapting the current controller parameters online, the system achieves fast and accurate tracking performance. The proposed current controllers are derived based on the system theoretic concept of exact input/output (I/O) linearization of the current dynamics. The use of analytical flux linkage prototype functions allows for consideration of magnetic saturation and cross-coupling effects, replacing the need for lookup tables.
IEEE OPEN JOURNAL OF THE INDUSTRIAL ELECTRONICS SOCIETY
(2022)
Article
Engineering, Electrical & Electronic
Shih-Wei Su, Christoph M. Hackl, Ralph Kennel
Summary: Physically motivated and analytical prototype functions are proposed to approximate the nonlinear flux linkages of nonlinear synchronous machines. These functions can mimic various saturation effects and allow for easy calculation of differential inductances.
IEEE OPEN JOURNAL OF THE INDUSTRIAL ELECTRONICS SOCIETY
(2022)
Article
Engineering, Electrical & Electronic
Julian Kullick, Christoph M. Hackl
Summary: The study presents a speed-sensorless state-feedback controller for induction machines, which performs well under various operating conditions. Stability and performance improvements are achieved through pre-tuned observer and control gains.
