The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Hong Wang - One of the best experts on this subject based on the ideXlab platform.
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Collaborative operational fault tolerant Control for stochastic Distribution Control system
Automatica, 2018Co-Authors: Yuwei Ren, Aiping Wang, Yixian Fang, Huaxiang Zhang, Hong WangAbstract:Abstract Based on a class of industrial processes, a new distributed fault diagnosis approach and a collaborative operational fault tolerant Control law are proposed for an irreversible interconnected stochastic Distribution Control (SDC) system with boundary conditions. This Control method is different from the existing collaborative fault tolerant Controllers which enable the output probability density function (PDF) to track a desired PDF as close as possible. When fault occurs, a setpoint redesigned fault tolerant approach is adopted to accommodate the fault instead of reconstructing the Controller. An augmented PID nominal Controller and a setpoint compensation item with linear structure are used to obtain a collaborative operational fault tolerant Controller via solution of linear matrix inequalities (LMIs). Simulations are included to show the effectiveness of the proposed algorithms where encouraging results have been obtained.
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iterative learning double closed loop structure for modeling and Controller design of output stochastic Distribution Control systems
IEEE Transactions on Control Systems and Technology, 2014Co-Authors: Jinglin Zhou, Hong Yue, Jinfang Zhang, Hong WangAbstract:Stochastic Distribution Control (SDC) systems are known to have the 2-D characteristics regarding time and probability space of a random variables, respectively. A double closed-loop structure, which includes iterative learning modeling (ILM) and iterative learning Control (ILC), is proposed for non-Gaussian SDC systems. The ILM is arranged in the outer loop, which takes a longer period for each cycle termed as a BATCH. Each BATCH is divided into a modeling period and a number of Control intervals, called batches, being arranged in the inner loop for ILC. The output probability density functions (PDFs) of the system are approximated by a radial basis function neural network (RBFNN) model, whose parameters are updated via ILM in each BATCH. Based on the RBFNN approximation of the output PDF, a state-space model is constructed by employing the subspace parameter estimation method. An IL optimal Controller is then designed by decreasing the PDF tracking errors from batch to batch. Model simulations are carried out on a forth-order numerical example to examine the effectiveness of the proposed algorithm. To further assess its application feasibility, a flame shape Distribution Control simulation platform for a combustion process in a coal-fired gate boiler system is constructed by integrating WinCC interface, MATLAB simulation programs, and OPC communication together. The simulation study over this industrial simulation platform shows that the output PDF tracking performance can be efficiently achieved by this double closed-loop iterative learning strategy.
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Recent advances on stochastic Distribution Control: Probability density function Control
2009 Chinese Control and Decision Conference, 2009Co-Authors: Aiping Wang, Hong Wang, Lei GuoAbstract:This semi-plenary paper presents a brief and selected survey on the advances on stochastic Distribution Control, where the purpose of the Controller design is to Control the shape of output probability density functions (pdf) of non-Gaussian and general stochastic systems. This research was motivated through the requirement of Distribution shape Control of a number of practical systems in 1996. Following the developments since 1996, much research has been performed internationally and journal special issues and invited session at major conferences have been seen since 2001. It is expected that this survey will provide readers with some up-to-date information on this new area.
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CDC - Direct solution of the parametric Stochastic Distribution Control problem
Proceedings of the 48h IEEE Conference on Decision and Control (CDC) held jointly with 2009 28th Chinese Control Conference, 2009Co-Authors: Puya Afshar, Amin Nobakhti, Hong WangAbstract:The Stochastic Distribution Control (SDC) problem is a generalised form of the minimum variance Control problem where non-Gaussian noise Distributions are encountered. The problem has been previously solved using two alternative approaches. When it is assumed that the output Probability Distribution Function (PDF) is measurable, then a parameterized Controller is obtained. If on the other hand this assumption is removed (which corresponds to most practical cases), then the Controller found is no longer parameterisable (i.e. it is a Control action sequence). Both these approaches have thus far been solved using local Newtonian methods. In this paper a third alternative is presented which combines the desirable features of the previous two methods by finding a parameterized Controller, without having to assume that the output PDF is directly measurable at the same time. In addition, global direct search algorithms are used to avoid convergence to local solutions. The approach is demonstrated on a SISO nonlinear system corrupted by non-Gaussian input noise.
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Distribution Control of 1D diffusion processes based on the coupling method
2004Co-Authors: X P Sun, Y J Wang, Hong WangAbstract:The stochastic Distribution Control of diffusion processes is described in this paper based upon the Kantorovich-Robinshtein-Wasserstein (KRW) metric. By using the coupling method and solution of a martingale problem, the KRW metric can be approximately expressed in a simple form where a sub-optimal Distribution Control of 1-dimensional diffusion processes can be derived via the state feedback. It has been shown that in some special cases, the stochastic Distribution Control problem can be transformed into a standard stochastic Control problem and then an optimal Control solution can be obtained. Examples are given to show correctness of the proposed solution.
K.a. Conner - One of the best experts on this subject based on the ideXlab platform.
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Uniform Voltage Distribution Control for Series Connected DC–DC Converters
IEEE Transactions on Power Electronics, 2007Co-Authors: Kasemsan Siri, Michael Willhoff, K.a. ConnerAbstract:This paper investigates applications of current-mode, shared-bus commercial-off-the-shelf (COTS) dc-dc converters to power system architectures configured as parallel-input, series-output (PISO) and series-input, parallel-output (SIPO). By employing a PISO (or SIPO) architecture, current-mode COTS converters can transform their system input voltage to higher (or lower) system output voltage, provide ease and flexibility of power expansion, and preserve system efficiencies equal to those of standalone converters. Nonuniform output (or input) voltages still exist within a PISO (or SIPO) power system using identical converters when the system lacks proper Distribution Control of the series connected output (or input) voltages-and thus, system reliability suffers from thermal overstress to the converters that contribute a greater portion of the output power. Through unified approaches of voltage Distribution Control for the PISO and SIPO architectures, a series-connected converter power system attains robust stability and reliability. Two effective approaches to uniform voltage Distribution Control-the central-limit and maximum-limit voltage Distribution-will be discussed. Both computer simulation and experimental prototypes validate both of the uniform voltage Distribution power converter architectures.
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Uniform Voltage Distribution Control for Paralleled-Input, Series-Output Connected Converters
2005 IEEE Aerospace Conference, 2005Co-Authors: Kasemsan Siri, K.a. Conner, C.h. TruongAbstract:This paper extends the application of current-mode, shared-bus converters to power system architectures configured as Parallel-Input, Series-Output (PISO). By employing a PISO interconnect method, current-mode commercial-off-the-shelf (COTS) dc-dc converters can deliver higher output voltages, provide flexible options for power system expansion, and preserve system efficiencies equal to that obtained from standalone converters. However, without proper Control, non-uniformly distributed voltages occur due to converter component mismatch. System reliability suffers as a result of thermal overstress to the converters that contribute a greater portion of the output power. Conversely, robust system stability and uniform output voltage Distribution among series-connected converters is realized through output voltage Distribution Control. Through both computer simulation and experimental prototype, the uniform voltage Distribution power converter architecture is validated and successfully applied during power converter burn-in testing whereby converter load energy is recycled to the power system input, resulting in 49% to 80% conservation of energy
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Uniform voltage Distribution Control for series-input parallel-output, connected converters
2006 IEEE Aerospace Conference, 1Co-Authors: Kasemsan Siri, Michael Willhoff, C.h. Truong, K.a. ConnerAbstract:This paper extends the application of current-mode, shared-bus converters to power system architectures configured as series-input, parallel-output (SIPO). By employing a SIPO interconnect method, current-mode commercial-off-the-shelf (COTS) dc-dc converters can transform higher input voltages into low output voltages, provide flexible options for power system expansion, and preserve system efficiencies equal to that obtained from standalone converters. However, without proper Control, converter internal component mismatch cause the input voltage to be non-uniformly distributed. System reliability suffers as a result of thermal overstress to the converters that contribute a greater portion of the input power. Conversely, robust system stability and uniform input voltage Distribution among series-connected converters is realized through input voltage Distribution Control. Through computer simulation and experimental prototype the uniform voltage Distribution power converter architecture is validated and successfully applied.
Kasemsan Siri - One of the best experts on this subject based on the ideXlab platform.
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Current-Sharing/Voltage-Distribution Control for Interconnected DC-DC Converters
5th International Energy Conversion Engineering Conference and Exhibit (IECEC), 2007Co-Authors: Kasemsan Siri, Michael WillhoffAbstract:This paper presents advanced interconnection and Control approaches for three currentmode, shared-bus converter architectures: (1) parallel-input parallel-output (PIPO), (2) parallelinput series-output (PISO), and (3) series-input parallel-output (SIPO). Without proper Control, nonuniform current sharing or voltage Distribution may exist among interconnected DC-DC converters, negatively impacting reliability. Using the Control schemes presented herein, reliable and robust power system performance is achievable from the series and/or parallel interconnection of commercial-off-the-shelf (COTS) DC-DC converters. In particular, PIPO connected COTS converters have been well-known and already achieved uniform current-sharing by using the provided parallel Control port as a common “shared bus” for commanding the parallel-connected converters to operate as voltage-Controlled current sources. This paper presents two Control alternatives for PIPO converter systems based on the “shared-bus” approach: (1) minimum-voltageerror shared-bus and (2) maximum-voltage-error shared-bus. Furthermore, the current-mode shared-bus converters extend their applications to power system architectures configured as PISO and SIPO. Employing a PISO (or SIPO) interconnect method, current-mode COTS converters can transform their system input voltages to higher (or lower) system output voltages, provide flexibility for power system expansion, and preserve system efficiencies equal to that obtained from stand-alone converters. The system achieves robust stability and uniform voltage sharing among series-connected converters through unique output and input voltage Distribution Control approaches for the PISO and SIPO power architectures. Two effective approaches to uniform voltage Distribution Control, the central-limit (CL) and maximum-limit (ML) Distribution, will be discussed. Both computer simulation and experimental prototypes validate both series-connected power converter architectures with the two Control approaches.
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Uniform Voltage Distribution Control for Series Connected DC–DC Converters
IEEE Transactions on Power Electronics, 2007Co-Authors: Kasemsan Siri, Michael Willhoff, K.a. ConnerAbstract:This paper investigates applications of current-mode, shared-bus commercial-off-the-shelf (COTS) dc-dc converters to power system architectures configured as parallel-input, series-output (PISO) and series-input, parallel-output (SIPO). By employing a PISO (or SIPO) architecture, current-mode COTS converters can transform their system input voltage to higher (or lower) system output voltage, provide ease and flexibility of power expansion, and preserve system efficiencies equal to those of standalone converters. Nonuniform output (or input) voltages still exist within a PISO (or SIPO) power system using identical converters when the system lacks proper Distribution Control of the series connected output (or input) voltages-and thus, system reliability suffers from thermal overstress to the converters that contribute a greater portion of the output power. Through unified approaches of voltage Distribution Control for the PISO and SIPO architectures, a series-connected converter power system attains robust stability and reliability. Two effective approaches to uniform voltage Distribution Control-the central-limit and maximum-limit voltage Distribution-will be discussed. Both computer simulation and experimental prototypes validate both of the uniform voltage Distribution power converter architectures.
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Uniform Voltage Distribution Control for Paralleled-Input, Series-Output Connected Converters
2005 IEEE Aerospace Conference, 2005Co-Authors: Kasemsan Siri, K.a. Conner, C.h. TruongAbstract:This paper extends the application of current-mode, shared-bus converters to power system architectures configured as Parallel-Input, Series-Output (PISO). By employing a PISO interconnect method, current-mode commercial-off-the-shelf (COTS) dc-dc converters can deliver higher output voltages, provide flexible options for power system expansion, and preserve system efficiencies equal to that obtained from standalone converters. However, without proper Control, non-uniformly distributed voltages occur due to converter component mismatch. System reliability suffers as a result of thermal overstress to the converters that contribute a greater portion of the output power. Conversely, robust system stability and uniform output voltage Distribution among series-connected converters is realized through output voltage Distribution Control. Through both computer simulation and experimental prototype, the uniform voltage Distribution power converter architecture is validated and successfully applied during power converter burn-in testing whereby converter load energy is recycled to the power system input, resulting in 49% to 80% conservation of energy
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Uniform voltage Distribution Control for series-input parallel-output, connected converters
2006 IEEE Aerospace Conference, 1Co-Authors: Kasemsan Siri, Michael Willhoff, C.h. Truong, K.a. ConnerAbstract:This paper extends the application of current-mode, shared-bus converters to power system architectures configured as series-input, parallel-output (SIPO). By employing a SIPO interconnect method, current-mode commercial-off-the-shelf (COTS) dc-dc converters can transform higher input voltages into low output voltages, provide flexible options for power system expansion, and preserve system efficiencies equal to that obtained from standalone converters. However, without proper Control, converter internal component mismatch cause the input voltage to be non-uniformly distributed. System reliability suffers as a result of thermal overstress to the converters that contribute a greater portion of the input power. Conversely, robust system stability and uniform input voltage Distribution among series-connected converters is realized through input voltage Distribution Control. Through computer simulation and experimental prototype the uniform voltage Distribution power converter architecture is validated and successfully applied.
Toshio Ogino - One of the best experts on this subject based on the ideXlab platform.
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Design of atomic step networks on Si(111) through strain Distribution Control
Journal of Applied Physics, 2004Co-Authors: Hiroo Omi, Toshio Ogino, Yoshikazu Homma, S. Stoyanov, Vesselin TonchevAbstract:We propose an alternative method to Control atomic step networks on silicon for future wafer-scale integration of self-assembling nanostructures. The method is the strain-Distribution-Control method that we have recently proposed in [H. Omi, D. J. Bottomley, and T. Ogino, Appl. Phys. Lett. 80, 1073 (2002)], which we apply here to design atomic step networks on vicinal Si(111) wafer. Si(111) with its strain patterned by buried silicon oxide inclusions was annealed at 1230 °C in ultrahigh vacuum and observed by in situ secondary electron microscopy and ex situ atomic force microscopy. The images show that the method enables us to create the desired arrays of atomic step networks on an arbitrary area of planar silicon wafer. The arrays remain stable during the 1230 °C annealing.
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Strain Distribution Control on the silicon wafer scale for advanced nanostructure fabrication
Applied Physics Letters, 2002Co-Authors: David J. Bottomley, Toshio OginoAbstract:Looking to the long-term future of Si semiconductor technology, we propose, fabricate, and demonstrate strain Distribution Control on the planar Si wafer scale for advanced nanostructure self-assembly. Oxygen ions are implanted through patterned layers on the Si wafer; the sample is then annealed at 1325 °C to produce bulk oxide inclusions which yield a strain Distribution. Strained epitaxial growth of Ge on the Si(001) substrate surface at 550 °C in ultrahigh vacuum produces three-dimensional islands whose location and size Distribution are well Controlled. The degree of localization Control is in agreement with simulations of the elastic strain Distribution.
Michael Willhoff - One of the best experts on this subject based on the ideXlab platform.
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Current-Sharing/Voltage-Distribution Control for Interconnected DC-DC Converters
5th International Energy Conversion Engineering Conference and Exhibit (IECEC), 2007Co-Authors: Kasemsan Siri, Michael WillhoffAbstract:This paper presents advanced interconnection and Control approaches for three currentmode, shared-bus converter architectures: (1) parallel-input parallel-output (PIPO), (2) parallelinput series-output (PISO), and (3) series-input parallel-output (SIPO). Without proper Control, nonuniform current sharing or voltage Distribution may exist among interconnected DC-DC converters, negatively impacting reliability. Using the Control schemes presented herein, reliable and robust power system performance is achievable from the series and/or parallel interconnection of commercial-off-the-shelf (COTS) DC-DC converters. In particular, PIPO connected COTS converters have been well-known and already achieved uniform current-sharing by using the provided parallel Control port as a common “shared bus” for commanding the parallel-connected converters to operate as voltage-Controlled current sources. This paper presents two Control alternatives for PIPO converter systems based on the “shared-bus” approach: (1) minimum-voltageerror shared-bus and (2) maximum-voltage-error shared-bus. Furthermore, the current-mode shared-bus converters extend their applications to power system architectures configured as PISO and SIPO. Employing a PISO (or SIPO) interconnect method, current-mode COTS converters can transform their system input voltages to higher (or lower) system output voltages, provide flexibility for power system expansion, and preserve system efficiencies equal to that obtained from stand-alone converters. The system achieves robust stability and uniform voltage sharing among series-connected converters through unique output and input voltage Distribution Control approaches for the PISO and SIPO power architectures. Two effective approaches to uniform voltage Distribution Control, the central-limit (CL) and maximum-limit (ML) Distribution, will be discussed. Both computer simulation and experimental prototypes validate both series-connected power converter architectures with the two Control approaches.
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Uniform Voltage Distribution Control for Series Connected DC–DC Converters
IEEE Transactions on Power Electronics, 2007Co-Authors: Kasemsan Siri, Michael Willhoff, K.a. ConnerAbstract:This paper investigates applications of current-mode, shared-bus commercial-off-the-shelf (COTS) dc-dc converters to power system architectures configured as parallel-input, series-output (PISO) and series-input, parallel-output (SIPO). By employing a PISO (or SIPO) architecture, current-mode COTS converters can transform their system input voltage to higher (or lower) system output voltage, provide ease and flexibility of power expansion, and preserve system efficiencies equal to those of standalone converters. Nonuniform output (or input) voltages still exist within a PISO (or SIPO) power system using identical converters when the system lacks proper Distribution Control of the series connected output (or input) voltages-and thus, system reliability suffers from thermal overstress to the converters that contribute a greater portion of the output power. Through unified approaches of voltage Distribution Control for the PISO and SIPO architectures, a series-connected converter power system attains robust stability and reliability. Two effective approaches to uniform voltage Distribution Control-the central-limit and maximum-limit voltage Distribution-will be discussed. Both computer simulation and experimental prototypes validate both of the uniform voltage Distribution power converter architectures.
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Uniform voltage Distribution Control for series-input parallel-output, connected converters
2006 IEEE Aerospace Conference, 1Co-Authors: Kasemsan Siri, Michael Willhoff, C.h. Truong, K.a. ConnerAbstract:This paper extends the application of current-mode, shared-bus converters to power system architectures configured as series-input, parallel-output (SIPO). By employing a SIPO interconnect method, current-mode commercial-off-the-shelf (COTS) dc-dc converters can transform higher input voltages into low output voltages, provide flexible options for power system expansion, and preserve system efficiencies equal to that obtained from standalone converters. However, without proper Control, converter internal component mismatch cause the input voltage to be non-uniformly distributed. System reliability suffers as a result of thermal overstress to the converters that contribute a greater portion of the input power. Conversely, robust system stability and uniform input voltage Distribution among series-connected converters is realized through input voltage Distribution Control. Through computer simulation and experimental prototype the uniform voltage Distribution power converter architecture is validated and successfully applied.