This paper is concerned with the problem of observer-based controller design for singular stochastic Markov jump systems with state-dependent noise. Two concepts called "non-impulsiveness"and "mean squa...This paper is concerned with the problem of observer-based controller design for singular stochastic Markov jump systems with state-dependent noise. Two concepts called "non-impulsiveness"and "mean square admissibility" are introduced, which are different from previous ones. Sufficient conditions for the open-and closed-loop singular stochastic Markov jump systems with state-dependent noise to be mean square admissible are provided in terms of strict LMIs. The controller gain and the observer gain which guarantee the resulting closed-loop error system to be mean square admissible are obtained in turn by solving the strict LMIs. A numerical example is presented to show the efficiency of the design approach.展开更多
Microgrid has emerged as an answer to growing demand for distributed generation(DG) in power systems. It contains several DG units including microalternator, photovoltaic system and wind generation. It turns out that ...Microgrid has emerged as an answer to growing demand for distributed generation(DG) in power systems. It contains several DG units including microalternator, photovoltaic system and wind generation. It turns out that sustained operation relies on the stability of these constituent systems. In this paper, a microgrid consisting of microalternator and photovoltaic system is modeled as a networked control system of systems(So S)subjected to packet dropouts and delays. Next, an observerbased controller is designed to stabilize the system in presence of the aforementioned communication constraints and simulation results are provided to support the control design methodology.展开更多
This paper investigates the problem of path tracking control for autonomous ground vehicles(AGVs),where the input saturation,system nonlinearities and uncertainties are considered.Firstly,the nonlinear path tracking s...This paper investigates the problem of path tracking control for autonomous ground vehicles(AGVs),where the input saturation,system nonlinearities and uncertainties are considered.Firstly,the nonlinear path tracking system is formulated as a linear parameter varying(LPV)model where the variation of vehicle velocity is taken into account.Secondly,considering the noise effects on the measurement of lateral offset and heading angle,an observer-based control strategy is proposed,and by analyzing the frequency domain characteristics of the derivative of desired heading angle,a finite frequency H_∞index is proposed to attenuate the effects of the derivative of desired heading angle on path tracking error.Thirdly,sufficient conditions are derived to guarantee robust H_∞performance of the path tracking system,and the calculation of observer and controller gains is converted into solving a convex optimization problem.Finally,simulation examples verify the advantages of the control method proposed in this paper.展开更多
This article concerns a coupled LMIs approach to delay-dependent observer-based output feedback stabilizing controller design for linear continuous-time systems with multiple state delays. The advantage of our propose...This article concerns a coupled LMIs approach to delay-dependent observer-based output feedback stabilizing controller design for linear continuous-time systems with multiple state delays. The advantage of our proposed delay-dependent coupled LMIs criterion lies in that: ( 1 ) it can optimize one of multiple time delays with others selected properly, and at the same time, the feedback-gain and observer-gain can be obtained, respectively. (2) it is less conservative than the existing delay-independent ones in the literature. Algorithm to solve the coupled LMIs is also given. Numerical examples illustrate the effectiveness of our method. Keywords Delay-dependent criterion - Time-delay system - Multiple time-delay - Observer-based controller - Linear matrixinequality (LMI)展开更多
Background A digital low level radio frequency(DLLRF)system has been developed to replace the old analog LLRF and operated stably at BEPCII east RF station in the past two years.The RF stabilities required for BEPCII ...Background A digital low level radio frequency(DLLRF)system has been developed to replace the old analog LLRF and operated stably at BEPCII east RF station in the past two years.The RF stabilities required for BEPCII are±1%in magnitude and±1 degree in phase.These are satisfied both by the new DLLRF and the old analog LLRF.Yet,the DLLRF did not improve the RF stabilities so much as expected,especially when the beam current was high in collision mode.Purpose The purpose is to improve the RF stabilities further and meet the requirements by the upgraded BEPCII project(BEPC3).Method A disturbance observer based(DOB)controller to suppress the noise was developed and tested with beam at BEPCII RF system.Results The DOB controller works and the RF stabilities with beam may be improved from±1%to less than±0.5%in magnitude and from±1 degree to less than±0.5 degrees in phase.展开更多
在工程实践中,针对工业过程的不确定性设计便于使用和维护的控制器具有重要意义.牛顿定律是广大工程技术人员最熟悉的物理定律之一,文章基于牛顿定律提出了一种无模型不确定性控制系统及其设计方法,该方法通过构建被控系统的位置、速度...在工程实践中,针对工业过程的不确定性设计便于使用和维护的控制器具有重要意义.牛顿定律是广大工程技术人员最熟悉的物理定律之一,文章基于牛顿定律提出了一种无模型不确定性控制系统及其设计方法,该方法通过构建被控系统的位置、速度和加速度三个状态变量,应用卡尔曼滤波器理论设计了牛顿运动力学观测器ONLM,并基于观测到的位置、速度和加速度设计了闭环系统补偿器,构成MFCNLM(Model-Free Control based on Newton’s Laws of Motion)无模型控制系统,使得系统输出跟踪期望的输出轨迹.本文更进一步地提出了PID(Proportional Integral Derivative)控制器设计的牛顿力学原理,分析和论证了MFCNLM控制方法与PID控制方法在控制系统设计上的牛顿力学统一性原理.文章所提出的设计方法不需要被控对象的数学模型,仅需控制工程师给出闭环控制系统期望的过渡过程时间T.文章给出了4个仿真研究和工程应用例子,具体展示了基于牛顿定律的MFCNLM控制系统与PID控制器的设计方法,结果表明所提方法对不确定系统具有良好的控制品质和鲁棒性能.展开更多
基金supported by the National Natural Science Foundation of China under Grant No.61573227the Research Fund for the Taishan Scholar Project of Shandong Province of China+1 种基金the SDUST Research Fund No.2015TDJH105the State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources under Grant No.LAPS16011
文摘This paper is concerned with the problem of observer-based controller design for singular stochastic Markov jump systems with state-dependent noise. Two concepts called "non-impulsiveness"and "mean square admissibility" are introduced, which are different from previous ones. Sufficient conditions for the open-and closed-loop singular stochastic Markov jump systems with state-dependent noise to be mean square admissible are provided in terms of strict LMIs. The controller gain and the observer gain which guarantee the resulting closed-loop error system to be mean square admissible are obtained in turn by solving the strict LMIs. A numerical example is presented to show the efficiency of the design approach.
基金supported by the Deanship for Scientific Research(DSR)at KFUPM through Distinguished Professorship Research Project(IN-141003)
文摘Microgrid has emerged as an answer to growing demand for distributed generation(DG) in power systems. It contains several DG units including microalternator, photovoltaic system and wind generation. It turns out that sustained operation relies on the stability of these constituent systems. In this paper, a microgrid consisting of microalternator and photovoltaic system is modeled as a networked control system of systems(So S)subjected to packet dropouts and delays. Next, an observerbased controller is designed to stabilize the system in presence of the aforementioned communication constraints and simulation results are provided to support the control design methodology.
基金supported by the National Natural Science Foundation of China(62173029,62273033,U20A20225)the Fundamental Research Funds for the Central Universities,China(FRF-BD-19-002A)。
文摘This paper investigates the problem of path tracking control for autonomous ground vehicles(AGVs),where the input saturation,system nonlinearities and uncertainties are considered.Firstly,the nonlinear path tracking system is formulated as a linear parameter varying(LPV)model where the variation of vehicle velocity is taken into account.Secondly,considering the noise effects on the measurement of lateral offset and heading angle,an observer-based control strategy is proposed,and by analyzing the frequency domain characteristics of the derivative of desired heading angle,a finite frequency H_∞index is proposed to attenuate the effects of the derivative of desired heading angle on path tracking error.Thirdly,sufficient conditions are derived to guarantee robust H_∞performance of the path tracking system,and the calculation of observer and controller gains is converted into solving a convex optimization problem.Finally,simulation examples verify the advantages of the control method proposed in this paper.
文摘This article concerns a coupled LMIs approach to delay-dependent observer-based output feedback stabilizing controller design for linear continuous-time systems with multiple state delays. The advantage of our proposed delay-dependent coupled LMIs criterion lies in that: ( 1 ) it can optimize one of multiple time delays with others selected properly, and at the same time, the feedback-gain and observer-gain can be obtained, respectively. (2) it is less conservative than the existing delay-independent ones in the literature. Algorithm to solve the coupled LMIs is also given. Numerical examples illustrate the effectiveness of our method. Keywords Delay-dependent criterion - Time-delay system - Multiple time-delay - Observer-based controller - Linear matrixinequality (LMI)
文摘Background A digital low level radio frequency(DLLRF)system has been developed to replace the old analog LLRF and operated stably at BEPCII east RF station in the past two years.The RF stabilities required for BEPCII are±1%in magnitude and±1 degree in phase.These are satisfied both by the new DLLRF and the old analog LLRF.Yet,the DLLRF did not improve the RF stabilities so much as expected,especially when the beam current was high in collision mode.Purpose The purpose is to improve the RF stabilities further and meet the requirements by the upgraded BEPCII project(BEPC3).Method A disturbance observer based(DOB)controller to suppress the noise was developed and tested with beam at BEPCII RF system.Results The DOB controller works and the RF stabilities with beam may be improved from±1%to less than±0.5%in magnitude and from±1 degree to less than±0.5 degrees in phase.
文摘在工程实践中,针对工业过程的不确定性设计便于使用和维护的控制器具有重要意义.牛顿定律是广大工程技术人员最熟悉的物理定律之一,文章基于牛顿定律提出了一种无模型不确定性控制系统及其设计方法,该方法通过构建被控系统的位置、速度和加速度三个状态变量,应用卡尔曼滤波器理论设计了牛顿运动力学观测器ONLM,并基于观测到的位置、速度和加速度设计了闭环系统补偿器,构成MFCNLM(Model-Free Control based on Newton’s Laws of Motion)无模型控制系统,使得系统输出跟踪期望的输出轨迹.本文更进一步地提出了PID(Proportional Integral Derivative)控制器设计的牛顿力学原理,分析和论证了MFCNLM控制方法与PID控制方法在控制系统设计上的牛顿力学统一性原理.文章所提出的设计方法不需要被控对象的数学模型,仅需控制工程师给出闭环控制系统期望的过渡过程时间T.文章给出了4个仿真研究和工程应用例子,具体展示了基于牛顿定律的MFCNLM控制系统与PID控制器的设计方法,结果表明所提方法对不确定系统具有良好的控制品质和鲁棒性能.
