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Smooth motion control of the adaptive cruise control system by a virtual lead vehicle

INTERNATIONAL JOURNAL OF AUTOMOTIVE TECHNOLOGY 2012年第1期13卷 77-85页

作者： Kim, S. G. Tomizuka, M. Cheng, K. H. Univ Calif Berkeley Dept Mech Engn Berkeley CA 94720 USA Ind Technol Res Inst Hsinchu 31040 Taiwan

The adaptive cruise control system maintains the appropriate distance to the lead vehicle when the lead vehicle exists and maintains the desired speed when no lead vehicle is detected. A virtual lead vehicle scheme is introduced to make the switching between the speed control algorithm and the distance control algorithm unnecessary and simplify the structure of the control system. The speed and the position of the virtual vehicle can be decided by the control system according to the current situation. Smoother responses are achieved by the virtual lead vehicle scheme compared to the conventional mode switching scheme. This method is also shown to provide a good reaction for when a lead vehicle cuts in or out. A linear quadratic controller with variable weights is suggested to control the virtual lead vehicle. This scheme shows improved performance in terms of passenger comfort and fuel efficiency of the host vehicle.

关键词： Automotive control Cruise control Vehicle dynamics Switching algorithms control algorithm

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Spacecraft Anti-Unwinding Attitude control with Actuator Nonlinearities and Velocity Limit

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JOURNAL OF GUIDANCE control AND DYNAMICS 2015年第10期38卷 2042-2049页

作者： Hu, Qinglei Li, Li Friswell, Michael I. Beihang Univ Sch Automat Sci & Elect Engn Beijing 100191 Peoples R China Harbin Inst Technol Sch Astronaut Harbin 150001 Peoples R China Univ Coll Swansea Coll Engn Swansea SA2 8PP W Glam Wales

The design of a stabilization control algorithm for spacecraft that accounts for actuator saturation, dead-zone nonlinearities, and a velocity limit to ensure a fast and accurate response is reported. This control algorithm is also designed to achieve effective compensation for external disturbances and parametric uncertainty. In addition, extensive simulations were performed using different actuator nonlinearities, disturbance inputs, and even random noise. These results showed that the attitude control and energy saving are accomplished despite these undesired effects in the system. Moreover, the flexibility in the choice of control parameters can be used to obtain desirable performance while meeting constraints on the control magnitude and velocity. These control approaches provide a theoretical basis for the practical application of the advanced control theory to spacecraft attitude control systems.

关键词： Actuators Spacecraft Performance Attitude control System Proportional Integral Derivative Spacecraft Attitude Quaternions Energy Consumption control algorithm International Space Station Variable Structure control

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BD-VSS individual weighting factor sign based adaptive filter control for power quality improvement in weak distribution grid

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IET GENERATION TRANSMISSION & DISTRIBUTION 2020年第8期14卷 1450-1457页

作者： Singh, Sunaina Kewat, Seema Singh, Bhim Panigrahi, B. K. Kushwaha, Manoj Kumar Vira Coll Engn Elect KSVCEM NH119Awas Vikas Rd Bijnor 246701 Uttar Pradesh India Indian Inst Technol Delhi Dept Elect Engn Delhi India

This study presents the control of distribution static compensator (DSTATCOM) using band-dependent variable step size (BD-VSS) individual weighting factor with sign error based adaptive filter for power quality improvement in a weak distribution grid. Here, the proposed algorithm is used for estimation of fundamental active weight components from the distorted load currents in order to generate the reference grid currents to mitigate the grid currents power quality issues. This new control algorithm is proposed for fast and accurate estimation of active weight components with low steady-state error, without dynamic oscillation at fast convergence speed. Moreover, the frequency locked loop-double self-tuning second-order generalised integrator based voltage filter is used to extract the positive sequence voltages of the distorted grid voltages for estimating the harmonics, and noise-free voltage unit templates. Therefore, the DSTATCOM with the proposed control algorithm is capable of mitigating the harmonic currents, providing reactive power compensation and operating at unity power factor in a weak distribution grid. Test results demonstrate the viability and robustness of the proposed control algorithm under balanced and unbalanced non-linear load conditions.

关键词： adaptive control power harmonic filters voltage control reactive power adaptive filters power grids power system harmonics frequency locked loops static VAr compensators electric current control power supply quality phase locked loops power factor active filters power filters BD-VSS individual factor sign adaptive filter control power quality improvement weak distribution grid fundamental active weight components distorted load currents reference grid currents grid currents power quality issues control algorithm fast estimation second-order generalised integrator based voltage filter distorted grid voltages noise-free voltage unit templates harmonic currents reactive power compensation unity power factor distribution static compensator band-dependent variable step size individual weighting factor sign error based adaptive filter

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Relative dynamics and control of spacecraft formations in eccentric orbits

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JOURNAL OF GUIDANCE control AND DYNAMICS 2002年第1期25卷 48-59页

作者： Inalhan, G Tillerson, M How, JP Stanford Univ Dept Aeronaut & Astronaut Stanford CA 94305 USA MIT Dept Aeronaut & Astronaut Cambridge MA 02139 USA

Formation flying is a key technology for both deep-space and orbital applications that involve multiple spacecraft. Many future space applications will benefit from using formation flying technologies to perform distributed observations (e.g., synthetic apertures for Earth mapping interferometry) and to provide improved coverage for communication and surveillance. Previous research has focused on designing passive apertures for these formation flying missions assuming a circular reference orbit. Those design approaches are extended and a complete initialization procedure for a large fleet of vehicles with an eccentric reference orbit is presented. The main result is derived from the homogenous solutions of the linearized relative equations of motion for the spacecraft. These solutions are used to find the necessary conditions on the initial states that produce T-periodic solutions that have the vehicles returning to the initial relative states at the end of each orbit, that is, nu(t(0)) = nu(t(0) + T). This periodicity condition and the resulting initialization procedure are originally given (in compact form) at the reference orbit perigee, but this is also generalized to enable initialization at any point around the reference orbit. In particular, an algorithm is given that minimizes the fuel cost associated with initializing the vehicle states (primarily the in-track and radial relative velocities) to values that are consistent with periodic relative motion. These algorithms extend and generalize previously published solutions for passive aperture forming with circular orbits. The periodicity condition and the homogenous solutions can also be used to estimate relative motion errors and the approximate fuel cost associated with neglecting the eccentricity in the reference orbit. The nonlinear simulations presented clearly show that ignoring the reference orbit eccentricity generates an error that is comparable to the disturbances caused by differential gravity acce

关键词： Orbital Elements Orbital Period Earth Spacecraft Formation Monolithic Satellite Earth Centered Inertial Synthetic Aperture Radar Feedback control System control algorithm Eccentric Anomaly

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Performance analysis of a multilevel inverter based shunt active filter with RT-EMD control technique under ideal and non-ideal supply voltage conditions

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IET GENERATION TRANSMISSION & DISTRIBUTION 2019年第18期13卷 4037-4048页

作者： Dash, Ashish Ranjan Panda, Anup Kumar Lenka, Rajesh Kumar Patel, Ranjeeta Natl Inst Technol Dept Elect Engn Rourkela 769008 India

In this study, a real-time empirical mode decomposition (RT-EMD) based control technique is adopted for effective mitigation of system harmonics under ideal and non-ideal supply voltage conditions. The proposed control algorithm takes the active component of load current samples and the positive sequence voltage component for generating the desired reference. The fundamental component of load current is found by employing RT-EMD, which decomposes the distorted non-linear sample into a finite number of fine-scale signals termed as intrinsic mode function (IMF). Each IMF is extracted adopting continuous calculation of upper and lower envelopes using a series pipeline structure which decreases the computational complexity. The proposed control algorithm takes the positive sequence voltage component for generating the desired reference so that the system can operate in non-sinusoidal grid voltage conditions. The proposed control algorithm adopts carrier-based modulation scheme for switching of the inverter module. The effectiveness of the proposed control approach is investigated in MATLAB-Simulink environment with balanced and unbalanced loading condition and its experimental validation is carried out by a hardware prototype model using a Spartan 6 FPGA controller.

关键词： active filters field programmable gate arrays PWM invertors electric current control power system harmonics power harmonic filters power convertors power grids invertors active filter RT-EMD control technique nonideal supply voltage conditions real-time empirical mode decomposition based control technique control algorithm active component load current samples positive sequence voltage component desired reference fundamental component employing RT-EMD nonlinear sample nonsinusoidal grid voltage conditions carrier-based modulation scheme control approach balanced loading condition unbalanced loading condition Spartan 6 FPGA controller

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Linear Matrix Inequality-Based Nonlinear Adaptive Robust control of Quadrotor

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JOURNAL OF GUIDANCE control AND DYNAMICS 2016年第5期39卷 996-1008页

作者： Kun, David W. Hwang, Inseok Purdue Univ Sch Aeronaut & Astronaut W Lafayette IN 47907 USA

In this paper, we propose a novel linear matrix inequality-based nonlinear adaptive robust control algorithm to design the attitude and position controllers for an X-configuration quadrotor helicopter. The inner loop of the autopilot controls the attitude and altitude of the quadrotor, and the outer loop controls its position in the Earth-fixed coordinate frame. By assuming knowledge of the bounds of the quadrotor's uncertain parameters (e.g., mass and moments of inertia) and predetermined bounds on the external and unstructured disturbances (e.g., wind gusts and unmodeled dynamics), we attain a guaranteed transient and steady-state tracking performance. We demonstrate the performance of the controllers via two illustrative examples. In the first example mission, the quadrotor follows an altitude reference trajectory in the presence of wind gusts and delivers a package of uncertain mass midflight. The second example presents an autonomous waypoint flight in the presence of wind disturbances. The results of our simulations indicate that our controller design is useful for a variety of quadrotor applications, including precise trajectory tracking, autonomous waypoint navigation in the presence of disturbances, and package delivery without loss of performance.

关键词： Quadrotor Helicopter Proportional Integral Derivative Earth control algorithm Autopilot Yaw Freestream Velocity Angle of Attack Heading Angle Federal Aviation Administration

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Design and control of an Optimized Battery Charger for an xEV Based on Photovoltaic Power Systems

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JOURNAL OF ELECTRICAL ENGINEERING & TECHNOLOGY 2014年第5期9卷 1602-1613页

作者： Kim, Dong-Hee Cheo, Gyu-Yeong Lee, Byoung-Kuk Sungkyunkwan Univ Sch Informat & Commun Engn Suwon South Korea Hyundai Kia Motor Co Elect Power Convers Syst Engn Design Team Seoul South Korea

The continuous growth of electric vehicles has caused electric power shortages in conventional utilities owing to the charging of electric-vehicle batteries. In order to increase the capacity of these utilities, photovoltaic systems may be an appropriate solution because of their benefits. However, a large amount of loss is generated in a conventional charging structure using photovoltaic sources owing to the many power conversion processes. This paper describes a simple integrated battery charger that utilizes a PV generation system. Moreover, the system control algorithm is deduced by analyzing the operation modes in order to control the proposed integrated system. The proposed system and algorithm are verified by a 3.3-kW prototype, resulting in an increase in the efficiency of approximately 7% to 15% compared with the conventional system. And, to examine the feasibility of the proposed system, the simulation for multi-charger with various conditions are progressed.

关键词： Battery charger control algorithm Electric vehicles Photovoltaic (PV) generation system System integration

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Event-Based Impulsive control for Spacecraft Rendezvous Hovering Phases

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JOURNAL OF GUIDANCE control AND DYNAMICS 2021年第10期44卷 1794-1810页

作者： Sanchez, Julio C. Louembet, Christophe Gavilan, Francisco Vazquez, Rafael Univ Seville Higher Sch Engn Dept Ingn Aerosp Seville 41092 Spain Univ Toulouse CNRS Lab Anal & Architecture Syst Natl Ctr Sci Res F-31400 Toulouse France Univ Toulouse Paul Sabatier Univ Lab Anal & Architecture Syst Toulouse France

This work presents an event-triggered controller for spacecraft rendezvous hovering phases. The goal is to maintain the chaser within a bounded region with respect to the target. The main assumption is that the chaser vehicle has impulsive thrusters. These are assumed to be orientable at any direction and are constrained by dead-zone and saturation bounds. The event-based controller relies on trigger rules deciding when a suitable control law is applied. The local control law consists on a single impulse;therefore the trigger rules design is based on the instantaneous reachability to the admissible set. The final outcome is a very efficient algorithm from both computational burden and footprint perspectives. Because the proposed methodology is based on a single impulse control, the controller invariance is local and assessed through impulsive systems theory. Finally, numerical results are shown and discussed.

关键词： Spacecraft Rendezvous Fuel Consumption Earth control algorithm Model Predictive control CubeSat International Space Station Automated Transfer Vehicle Earth Centered Inertial Atmospheric Drag

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Mathematical-based control method and performance analysis of a novel hydromechatronics driving system micro-independent metering

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MATHEMATICAL METHODS IN THE APPLIED SCIENCES 2022年第4期45卷 2443-2459页

作者： Abuowda, Karem Dupac, Mihai Noroozi, Siamak Godfrey, Philip Bournemouth Univ Dept Design & Engn Poole Dorset England HYDRECO Hydraul Ltd Design Engn Dept Poole Dorset England

This paper aims to investigate the performance of a hydraulic actuator controlled by the novel system microindependent metering (MIM). This analysis has been performed by comparing the models of two systems which are the traditional independent metering (IM), which depends on poppet valve, and the new hydro-mechatronics system MIM, which relies on a stepped rotary flow control valve. In general, IM is a hydraulic control system which guarantees a separation between the meter-in and the meter-out of the hydraulic actuator. A Valvistor valve, a special type of Poppet valves, was developed to be embedded into the IM system. This valve has controllability and stability shortcomings which prevent the system from spreading in the industrial applications. The Valvistor valve performance is highly affected by the fluid disturbances because the fluid is considered as a part of its control elements. A stepped rotary flow control valve has been developed to control hydraulic flow rate. The valve composed of a rotary orifice attached to a stepper motor. Using this valve instead of the traditional poppet type has led to a new configuration, which is termed by MIM. This form improves the hydraulic cylinder velocity performance by rejecting the fluid disturbances effect on the control circuit.

关键词： control algorithm fluid mechanics independent metering microindependent metering

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Nonlinear control of a 20-story steel building with active piezoelectric friction dampers

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STRUCTURAL ENGINEERING AND MECHANICS 2002年第1期14卷 21-38页

作者： Chen, CQ Chen, G Univ Missouri Dept Civil Engn Rolla MO 65409 USA

A control algorithm combining viscous and non-linear Reid damping mechanisms has been recently proposed by the authors to command active friction dampers. In this paper. friction dampers and the proposed algorithm are applied to control the seismic responses of a nonlinear 20-story building. Piezoelectric stack actuators are used to implement the control algorithm. The capacity of each damper is determined by the practical size of piezoelectric actuators and the availability of power supply. The saturation effect of the actuators on the building responses is investigated. To minimize the peak story drift ratio or floor acceleration of the building structure, a practical sequential procedure is developed to sub-optimally place the dampers on various floors. The effectiveness of active friction dampers and the efficiency of the proposed sequential procedure are verified by subjecting the building structure to four earthquakes of various intensities. The performance of 80 dampers and 137 dampers installed on the structure is evaluated according to 5 criteria. Numerical simulations indicated that the proposed control algorithm effectively reduces the seismic responses of the uncontrolled 20-story building, such as inelastic deformation. The sub-optimal placement of dampers based on peak acceleration outperforms that based on peak drift ratio for structures subjected to near-fault ground motions. Saturation of piezoelectric actuators has adverse effect on floor acceleration.

关键词： active control piezoelectric friction damper steel moment resisting frame inelastic responses control algorithm seismic performance near-fault effect

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