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LIGHT IMPULSIVE DAMPING OF SPACECRAFT EXHIBITING NORMAL MODE BEHAVIOR

JOURNAL OF GUIDANCE control AND DYNAMICS 1992年第1期15卷 114-120页

作者： SILVERBERG, L North Carolina State University Raleigh North Carolina 27695

This paper develops an impulsive damping control algorithm suitable for spacecraft. The fuel optimal solutions to the problem of damping the motion of spacecraft consists of impulsive control forces applied al repealed instances in time. The instances in time occur when the spacecraft undergoes maximum absolute velocities and minimum absolute displacements. This paper approximates impulses by short duration pulses. Maximum absolute velocities and minimum absolute displacements are then approximated by transient values of their respective standard deviations. Impulsive damping is achieved by applying either a large single pulse or smaller repeated pulses. A near fuel optimal mode preserving impulsive damping control algorithm is developed next. The algorithm exhibits the following properties: 1) the impulsive damping control algorithm is independent of spacecraft stiffness, 2) the associated control forces are proportional to spacecraft inertia, and 3) the impulsive damping control algorithm is decentralized. The impulsive damping of a cantilever beam demonstrates the results.

关键词： Flexible Spacecrafts Standard Deviation control algorithm Cantilever Beam Harmonic Oscillator Optimal control Discrete control Spacecraft control Newton's Laws of Motion Boundary Value Problems

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Unbalanced normal force reduction in the eccentric double-sided linear switched reluctance machine

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IET ELECTRIC POWER APPLICATIONS 2016年第5期10卷 384-393页

作者： Wang, Qianlong Chen, Hao Nie, Rui China Univ Min & Technol Sch Informat & Elect Engn Xuzhou Peoples R China

This paper presents a novel control method for unbalanced normal force (UNF) reduction in the eccentric double-sided linear switched reluctance machine (DLSRM). Online detection of the DLSRM eccentricity is investigated via magnetic circuit analysis as well as finite element method. It is shown that the DLSRM eccentricity is directly proportional to the difference between reciprocal values of winding unsaturated inductances on both sides of the DLSRM mover. In order to improve the accuracy of the eccentricity detection, a new scheme to estimate the winding inductances is proposed on the basis of the voltage pulse injection considering iron losses in the test DLSRM in the laboratory. Afterward, a control algorithm for the UNF reduction, according to the estimated real-time eccentricity, is designed, and the corresponding power converter and flow chart are illustrated in detail. To verify the proposed methods, a prototype experimental platform is developed, and the experimental results confirm that the proposed methods in this study are feasible and effective.

关键词： reluctance machines magnetic circuits finite element analysis machine windings flowcharting unbalanced normal force reduction eccentric double-sided linear switched reluctance machine DLSRM eccentricity online detection magnetic circuit analysis finite element method winding inductances voltage pulse injection control algorithm UNF reduction power converter flow chart

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Vision-Based Obstacle Avoidance of Wheeled Robots Using Fast Estimation

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JOURNAL OF GUIDANCE control AND DYNAMICS 2009年第6期32卷 1931-1937页

作者： Dippold, Amanda Ma, Lili Hovakimyan, Naira Virginia Polytech Inst & State Univ Dept Aerosp & Ocean Engn Blacksburg VA 24060 USA Wentworth Inst Technol Dept Elect & Mech Boston MA 02135 USA Univ Illinois Urbana IL 61801 USA

A baseline path-following controller with an online obstacle-avoidance algorithm such that the robot tracks a prespecified path and avoids isolated obstacles using only visual information collected from an onboard camera. The visual information collected by the camera is processed by an estimator providing the inputs that includes estimation of the obstacle's position and size to the obstacle-avoidance algorithm. The obstacle-avoidance algorithm uses a potential function that yields larger values for paths that are close to obstacles and lower values for paths that are far from obstacles. The obstacle-avoidance method deforms the original path on a kinematic level in real time to move away from obstacles and ensures that the new path is collision free. In the vision-based range identification problem relative range is estimated between the vehicle and an obstacle with the use of a fast-estimation scheme. The fast estimator allows for fast adaptation of the unknown parameter via a large adaptation gain and low-pass filter.

关键词： Obstacle Avoidance Wheeled Robot Unscented Kalman Filter Mobile Robots Image Processing Inertial Measurement Unit Detect and Avoid Path Planning Artificial Potential Fields control algorithm

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Development of 8 MW Power Supply Based on Pulse Step Modulation Technique for Auxiliary Heating System on HL-2A

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Plasma Science and Technology 2012年第3期14卷 263-268页

作者：徐伟东宣伟民姚列英王英翘 Southwestern Institute of Physics Institute of Electrical Engineering Chinese Academy of Sciences

The high voltage power supply （HVPS） based on pulse step modulation （PSM） has already been developed for the auxiliary heating system on HL-2A. This power supply consists of many switch power supplies, and its output voltage can be obtained by modulating their delay time and pulse widths. The PSM topology and control principle are presented in this paper. The simple algorithms for the control system are explained clearly. The switch power supply （SPS） module has been built and the test results show it can meet the requirements of the auxiliary heating system. Now, 112 SPS modules and the whole system have already been developed. Its maximum output is about 72 kV/93 A. The protection time is less than 5 t＊s. The different outputs of this power supply are used for the electron cyclotron resonant heating （ECRH） system with different duty ratios. The experimental results of the entire system are presented. The results indicate that the whole system can meet the requirements of the auxiliary heating system on HL-2A.

关键词： PSM HV power supply control algorithm switch power supply module

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Adaptive Dynamic Surface Guidance Law with Input Saturation Constraint and Autopilot Dynamics

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JOURNAL OF GUIDANCE control AND DYNAMICS 2016年第5期39卷 1152-1159页

作者： Zhou, Di Xu, Biao Harbin Inst Technol Dept Control Sci & Engn Mailbox 327 Harbin 150001 Peoples R China

A novel guidance law with input saturation constraint and autopilot dynamics is designed using block dynamic surface control. Different from conventional dynamic surface control, which employs n-1 low-pass filters to avoid the complexity arising from the explosion of terms, in the designing process of the guidance law, n low-pass filters have been used, where the extra auxiliary low-pass filter is able to compensate for the effect of input saturation. The guidance command is derived by regarding the target maneuvers as bounded disturbance inputs whose upper bound can be estimated online by an adaptation law. The guidance law is able to provide a high guidance precision on intercepting either a non-maneuvering target or a maneuvering target because it is robust against disturbances. Numerical simulations show that the proposed guidance law offers better performance than some other advanced guidance laws, which have not taken autopilot dynamics into account.

关键词： Guidance System Autopilot Terminal Guidance Lyapunov Stability Theory Interceptor Missile Proportional Navigation Heading Angle Numerical Simulation control algorithm Interceptor Guidance

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SIMPLIFIED IMC-PID TUNING RULES

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ISA TRANSACTIONS 1994年第1期33卷 43-59页

作者： FRUEHAUF, PS CHIEN, IL LAURITSEN, MD Applied Control Engineering P.O. Box 520 Hockessin DE 19707 USA Department of Chemical Engineering Chang Gung College of Medicine and Technology Kwetshan Taoyuan ROC Taiwan DuPont Engineering 140 Cypress Station Drive Houston TX 77090 USA

We have significantly simplified the IMC-PID tuning rules. These new rules cover the vast majority of control loops encountered in the chemical industry. This work is the result of a great deal of experience in successfully applying IMC-PID tuning rules and an effort to prepare a training course on controller tuning. The simplified rules are very similar in form to the classic open loop Ziegler-Nichols rules and use the process reaction curve method for process testing. The two differences are that these rules are based on a less aggressive performance criteria and that we adapt the rules for some commonly encountered special cases. This paper presents the relationship between the simplified IMC-PID rules, the general IMC-PID rules, the Ziegler-Nichols rules and the Cohen-Coon rules. We show that the simplified rules are less sensitive to parameter mis-estimation than other more aggressive tuning rules. We also proposed rules for a fourth action;filtering. Filtering is available in digital controllers and smart field transmitters. We report that filtering and derivative action cancel each other and therefore should not be used together. We briefly outline the contents of the tuning course and finish the paper with an industrial example where the simplified rules have been successfully applied.

关键词： controlLER TUNING control algorithm

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Rejecting fast narrow-band disturbances with slow sensor feedback for quality beam steering in selective laser sintering

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MECHATRONICS 2018年 56卷 166-174页

作者： Xiao, Hui Jiang, Tianyu Chen, Xu Univ Connecticut Dept Mech Engn Storrs CT 06269 USA

A fundamental problem arises in feedback control when the system is subject to fast disturbances but can only get slowly updated sensor feedback. The problem is particularly challenging when the disturbances have frequency components near or beyond the sensor's Nyquist sampling frequency. Such difficulties occur to selective laser sintering, an additive manufacturing process that employs galvo scanners to steer high-power laser beams and relies on non-contact, slow sensing such as visual feedback to enhance the product quality. In pursuit of addressing the fundamental challenge in quality control under slow sensor feedback, this paper introduces a multi-rate control scheme to compensate beyond-Nyquist disturbances with application to selective laser sintering. This is achieved by designing a special bandpass filter with tailored frequency response beyond the slow Nyquist frequency of the sensor, along with integrating model-based predictor that reconstructs signals from limited sensor data. Verification of the algorithm is conducted by both simulation and experimentation on a galvo scanner that directs the energy beam in the additive manufacturing process.

关键词： Disturbance rejection Nyquist frequency control algorithm Selective laser sintering

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Enhancing Power Module Lifespan Through Power Distribution Approaches in a Three-Phase Interleaved DC/DC Converter

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IEEE ACCESS 2023年 11卷 96784-96796页

作者： Tavcar, Rok Bordignon, Gabriela Maria Munoz-Aguilar, Raul Santiago Zajec, Peter Yazaki Syst Technol GmbH D-93059 Regensburg Germany AVL Software & Funct GmbH D-93059 Regensburg Germany Maschinenfabr Reinhausen GmbH D-93059 Regensburg Germany Univ Ljubljana Fac Elect Engn SI-1000 Ljubljana Slovenia

This paper comprehensively analyzes various power distribution approaches to balance the stress on power modules (PM) in a three-phase interleaved DC/DC converter and increase its lifespan. Two implementations of power distribution are investigated: a symmetrical approach, where the PM utilizations are balanced by controlling the duration of their active intervals, and an asymmetrical approach, achieved by adjusting their reference currents. Regardless of the power distribution method, the estimation of accumulated PM stress is evaluated using two utilization metrics: energy-related and current-related. Different utilization and distribution control algorithms are validated using a hardware-in-the-loop (HiL) simulation setup, considering varying load profiles. The additional control modules require only minor modifications to the conventional two-loop controller structure, exhibit consistent responses, and steadily reduce the balance mismatch for all control combinations. The results demonstrate that asymmetrical control combined with energy utilization estimation yields the most favorable balance mismatch rate. Moreover, this methodology demonstrates superior energy efficiency in intervals characterized by balance mismatch, though it necessitates a significant initial labor investment for constructing the thermal mode.

关键词： Interleaved converter SiC MOSFET power distribution switch utilization thermal model load balancing control algorithm enhanced lifespan hardware-in-the-loop

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Time-averaged active controller for turbofan engine fan noise reduction

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JOURNAL OF AIRCRAFT 1996年第3期33卷 524-531页

作者： Thomas, RH Burdisso, RA Lane, SA Virginia Polytechnic Institute and State University Blacksburg Virginia 24061-0238

An active control system has been developed and used experimentally on an operational turbofan engine to reduce inlet tonal noise at the Pan blade passage frequency. Both single channel and multichannel systems were tested. The control approach used is the feedforward derivative measurement time-averaged adaptive algorithm. This algorithm is capable of adapting to a nonstationary system, requiring no prior knowledge of the system, A reference sensor mounted in the casing: of the fan provides the fan blade passing frequency reference signal to the controller. Microphones with a large sensing area are placed in the acoustic far field of the engine. The control algorithms minimize a cost function, the sum of the error signal mean-square-values, by activating loudspeakers that are mounted around the inlet of the engine. The control signals are obtained by filtering the reference signal with finite impulse response digital filters, The control algorithm finds the optimum Biter weights by using statistical estimates of the cost function to be minimized. A single channel control system was tested on an axisymmetric dominant mode case and produced reductions of up to 17 dB at the error microphone. The controller maintained reductions in the fan tone even as the engine speed was increased. In a traverse of the radiated sound held of the engine the fan blade passage tone was reduced over a sector of 30 deg around the error sensor with a considerable spillover increase in the fan tone outside of this sector, Two six channel control systems were developed and tested on both axisymmetric and spinning mode dominant cases, Reductions of up to 19.7 dB were achieved over large sectors around the error microphones with significantly reduced spillover.

关键词： Turbofan Engines Blade Passing Frequency Active control Eddy Current Sensors Digital Filters control algorithm Adaptive algorithm Newton's Method Sound Pressure Level Angle of Attack

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Power electronics active shunt filter with controlled dynamics

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COMPEL-THE INTERNATIONAL JOURNAL FOR COMPUTATION AND MATHEMATICS IN ELECTRICAL AND ELECTRONIC ENGINEERING 2013年第4期32卷 1337-1344页

作者： Gwozdz, Michal Poznan Univ Tech Fac Elect Engn Inst Elect Engn & Elect Poznan Poland

Purpose - The aim of the research was to find a structure of the power electronics controlled current source with extended pass band, which would better match a source output current within an input (reference) signal. Also, pulse modulation components in output current of current source should be minimized. Design/methodology/approach - The power electronics controlled current source utilizes both, the concept of the inductor with variable (controlled) inductance located at the output of an inverter and the concept of the multi-channel (interleaved) inverter. The small signal (linear) and simulation models of an active filter have been investigated. Findings - The work presents the concept of 1-phase active shunt filter with utilization of the power electronics current source about extended pass-band. Research limitations/implications - The research should be continued to achieve stability of the electrical system with variable parameters of the power network and receiver. Practical implications - The research will be continued towards realization of a laboratory model of a 3-phase active shunt filter with the DSP based control module. Social implications - Social implications are difficult to determine. Originality/value - The paper presents a new concept of the precision power electronics controlled current source with the extended pass-band. The controlled current source is the fundamental block of a power electronics active shunt filter.

关键词： control algorithm Current source Inverter Power electronics active filter Pulse modulation Simulation model Modulation methods Electronic engineering

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